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Sample records for acrylate ethyl acrylate

  1. GENOTOXICITY OF ACRYLIC ACID, METHYL ACRYLATE, ETHYL ACRYLATE, METHYL METHACRYLATE, AND ETHYL METHACRYLATE IN L5178Y MOUSE LYMPHOMA CELLS (JOURNAL VERSION)

    EPA Science Inventory

    A series of monomeric acrylate/methacrylate esters (methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate) as well as acrylic acid were examined for genotoxic activity in L5178Y mouse lymphoma cells without exogenous activation. All five compounds induced c...

  2. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  3. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare a scan from 10.5 microns...

  4. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  5. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  6. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  7. [Reaction of 1,8-naphthyridine azides with ethyl acrylate].

    PubMed

    Livi, O; Ferrarini, P L; Bertini, D; Tonetti, I

    1975-12-01

    The reaction of 1,8-naphthyridine azides with ethyl acrylate leads to the formation of 2-pyrazolines instead of 1,2,3-triazolines. Some of the compounds obtained have undergone pharmacological and microbiological (antibacterial) testing. PMID:1204828

  8. Base-Mediated Stereospecific Synthesis of Aryloxy and Amino substituted Ethyl Acrylates

    PubMed Central

    Namjoshi, Ojas A.; Verma, Ranjit; Lorenz, Michael; Tiruveedhula, V. V. N. Phani Babu; Monte, Aaron; Bertz, Steven H.

    2011-01-01

    The stereospecific synthesis of aryloxy and amino substituted E- and Z-ethyl-3-acrylates is of interest because of their potential in the polymer industry and in medicinal chemistry. During work on a copper-catalyzed cross-coupling reaction of E- and Z-ethyl-3-iodo-acrylates with phenols and N-heterocycles, we discovered a very simple (non-metallic) method for the stereospecific synthesis of aryloxy and amino substituted acrylates. To study this long standing problem on the stereoselectivity of aryloxy and amino substituted acrylates, a series of O- and N-substituted nucleophiles was allowed to react with E- and Z-ethyl-3-iodo-acrylates. Screening of different bases indicated that DABCO (1,4-diazabicyclo[2.2.2]octane) afforded successful conversion of E- and Z- ethyl-3-iodoacrylates into aryloxy and amino substituted ethyl acrylates in a stereospecific manner. Herein are the details of this DABCO-mediated stereospecific synthesis of aryloxy and amino substituted E- or Z-acrylates. PMID:22073965

  9. CYTOGENETIC STUDIES OF ETHYL ACRYLATE USING C57BL/6 MICE

    EPA Science Inventory

    The clastogenicity of ethyl acrylate (EA) was examined in vivo by injecting i.p. 5 male C57BL/6 mice per dose group with either 125, 250, 500, 1000 mg/kg EA dissolved in saline. wenty-four hours after injection, the animals were anesthetized, the spleens aseptically removed, and ...

  10. Methyl acrylate

    Integrated Risk Information System (IRIS)

    Methyl acrylate ; CASRN 96 - 33 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  11. Acrylic acid

    Integrated Risk Information System (IRIS)

    Acrylic acid ( CASRN 79 - 10 - 7 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  12. Semiconductor nanoparticles in poly((2-dimethylamino)ethyl methacrylate-co-acrylic acid) co-polymers

    NASA Astrophysics Data System (ADS)

    Trandafilović, L. V.; Bibić, N.; Georges, M. K.; Blanuša, J.; Radhakrishnan, T.; Djoković, V.

    2013-11-01

    Nanostructured cadmium selenide (CdSe) and lead sulfide (PbS) semiconductors were prepared in a poly(2-(dimethylamino)ethyl methacrylate-co-acrylic acid) matrix. The obtained nanoparticles were characterized by using optical and structural methods. Co-polymers were synthesized in two different molar ratios of pDMAEMA:acrylic acid monomer units (1:2, 1:1). Transmission electron microscopy analysis confirmed the presence of nano-sized CdSe and PbS particles. In the case of CdSe, a shift of the onset of the optical absorption toward lower wavelengths was observed. X-ray diffraction analysis revealed that both CdSe and PbS nanoparticles have cubic crystal structure.

  13. Ferromagnetic resonance spectroscopy of carboxylated cobalt-containing nanocomposite ethyl methacrylate/acrylic acid copolymers

    NASA Astrophysics Data System (ADS)

    Voytsihovskaya, S. A.; Sokolov, M. E.; Panyushkin, V. T.; Gromov, P. Yu.; Shcherbina, A. A.; Matveev, V. V.

    2013-01-01

    We have used ferromagnetic resonance spectroscopy to study the effect of the concentration of cobalt nanoparticles (5-9 nm) incorporated into ethyl methacrylate/acrylic acid copolymers (monomer ratios 100:1 and 10:1) on the magnitude of the resonant field in ferromagnetic resonance and on the effective magnetization of thin-film samples of these nanocomposite polymer materials. The cobalt nanoparticles were obtained by thermolysis of Co2(CO)8 in 5% solutions of the indicated copolymers in toluene. From the solutions obtained, we prepared films of thickness 1 μm on aluminum substrates.

  14. Ethyl 3-(4-hydroxy-phen-oxy)-2-(4-methoxy-phen-yl)acrylate.

    PubMed

    Hou, Jin

    2008-01-01

    In the title compound, C(18)H(18)O(5), the dihedral angle between the two benzene rings is 55.2 (3)°. The ethyl acrylate linkage is planar and forms dihedral angles of 21.3 (3) and 41.0 (3)°, respectively, with the hydroxy-phenyl and methoxy-phenyl rings. In the crystal structure, mol-ecules are linked into zigzag chains along the b axis by O-H⋯O hydrogen bonds. PMID:21581271

  15. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) The acrylate ester copolymer is a fully polymerized copolymer of ethyl acrylate, methyl methacrylate... emulsion defoamer. Disodium hydrogen phosphate Do. Formaldehyde Glyceryl monostearate Methyl...

  16. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) The acrylate ester copolymer is a fully polymerized copolymer of ethyl acrylate, methyl methacrylate... emulsion defoamer. Disodium hydrogen phosphate Do. Formaldehyde Glyceryl monostearate Methyl...

  17. Enhancing dry adhesives and replica molding with ethyl cyano-acrylate

    NASA Astrophysics Data System (ADS)

    Bovero, E.; Menon, C.

    2014-08-01

    The use of cyano-acrylate to improve the performance of dry adhesives and their method of fabrication is investigated. Specifically, the contributions of this work are: (1) a new adhesion method to adhere to a large variety of surfaces, (2) a strategy to increase the compliance of dry adhesives, and (3) an improved fabrication process for micro-structured dry adhesives based on replica molding. For the first contribution, the adhesion method consists of anchoring a micro-structured dry adhesive to a surface through a layer of hardened ethyl cyano-acrylate (ECA). This method increases the adhesion of the orders of magnitude at the expense of leaving residue after detachment. However, this method preserves reusability. For the second contribution, a double-sided dry adhesive is obtained by introducing a substrate with a millimeter-sized pillar structure, which enabled further increasing adhesion. For the third contribution, an ECA layer is used as a mold for the fabrication of new adhesives. These new types of molds proved able to produce dry adhesives with high reproducibility and low degradation.

  18. Scaffolds of Hyaluronic Acid-Poly(Ethyl Acrylate) Interpenetrating Networks: Characterization and In Vitro Studies.

    PubMed

    Rodríguez-Pérez, E; Lloret Compañ, A; Monleón Pradas, M; Martínez-Ramos, C

    2016-08-01

    Hyaluronic acid (HA) provides many advantages to regenerative implants through its bioactive properties, but it also has many limitations as a biomaterial if it is not chemically modified. In order to overcome some of these limitations, HA has been combined with poly(ethyl acrylate) in the form of interpenetrating polymeric networks (IPNs), in which the HA network is crosslinked with divinyl sulfone. Scaffolds of this IPN have been produced through a template-leaching methodology, and their properties have been compared with those of single-network scaffolds made of either PEA or crosslinked HA. A fibroblast cell line has been used to assess the in vitro performance of the scaffolds, revealing good cell response and a differentiated behavior on the IPN surface when compared to the individual polymers. Altogether, the results confirm that this type of material offers an interesting microenvironment for cells, which can be further improved toward its potential use in medical implants. PMID:27072058

  19. Computational study of the reaction mechanism and kinetics of ethyl acrylate ozonolysis in atmosphere

    NASA Astrophysics Data System (ADS)

    Sun, Yanhui; Cao, Haijie; Han, Dandan; Li, Jing; He, Maoxia; Wang, Chen

    2012-06-01

    The reaction mechanism for the ozonolysis of ethyl acrylate (EA) has been investigated at the CCSD(T)/6-31G(d)+CF//B3LYP/6-31+G(d,p) level of theory. The profile of the potential energy surface (PES) is constructed. Ozone adds to EA via a cyclic transition state to produce a highly unstable primary ozonide which can decompose readily. Over the temperature range of 200-2000 K, the total and individual rate constants are obtained by employing multichannel Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The calculated rate constants are 1.37 × 10-18 cm3 molecule-1 s-1 at 294 K and 1.65 × 10-18 cm3 molecule-1 s-1 at 298 K under the pressure of 760 Torr. The main products of the reactions are ethyl glyoxylate and formaldehyde. These results are in good agreement with the previous experimental data. Several experimental uncertain products are identified. The branching ratios of main reaction paths are also discussed at different temperatures and pressures.

  20. Silicone/Acrylate Copolymers

    NASA Technical Reports Server (NTRS)

    Dennis, W. E.

    1982-01-01

    Two-step process forms silicone/acrylate copolymers. Resulting acrylate functional fluid is reacted with other ingredients to produce copolymer. Films of polymer were formed by simply pouring or spraying mixture and allowing solvent to evaporate. Films showed good weatherability. Durable, clear polymer films protect photovoltaic cells.

  1. Antistatic coating for acrylics

    NASA Technical Reports Server (NTRS)

    Hadek, V.; Rembaum, A.; Somono, R. B.

    1979-01-01

    After immersion in low molecular-weight solvents such as acetonitril or nitromethane, clear acrylic plastics dissipate up to 70% of induced electric charge within one minute, yet retain optical clarity.

  2. The acrylic jacket crown.

    PubMed

    Bell, A M

    1975-04-01

    An attempt has been made to cover briefly the many applications of the acrylic jacket crown. It is readily understandable that this type of restoration has many shortcomings but at the same time it has many useful and important applications in dentistry when properly employed. It is hoped that the specialist and generalist alike will have found some new and useful applications of the acrylic jacket crown. PMID:1090464

  3. Biointegration of corneal macroporous membranes based on poly(ethyl acrylate) copolymers in an experimental animal model.

    PubMed

    Alió del Barrio, Jorge L; Chiesa, Massimo; Gallego Ferrer, Gloria; Garagorri, Nerea; Briz, Nerea; Fernandez-Delgado, Jorge; Sancho-Tello Valls, Maria; Botella, Carmen Carda; García-Tuñón, Ignacio; Bataille, Laurent; Rodriguez, Alejandra; Arnalich-Montiel, Francisco; Gómez Ribelles, Jose L; Antolinos-Turpín, Carmen M; Gómez-Tejedor, Jose A; Alió, Jorge L; De Miguel, Maria P

    2015-03-01

    Currently available keratoprosthesis models (nonbiological corneal substitutes) have a less than 75% graft survival rate at 2 years. We aimed at developing a model for keratoprosthesis based on the use of poly(ethyl acrylate) (PEA)-based copolymers, extracellular matrix-protein coating and colonization with adipose-derived mesenchymal stem cells. Human adipose tissue derived mesenchymal stem cells (h-ADASC) colonization efficiency of seven PEA-based copolymers in combination with four extracellular matrix coatings were evaluated in vitro. Then, macroporous membranes composed of the optimal PEA subtypes and coating proteins were implanted inside rabbit cornea. After a 3-month follow-up, the animals were euthanized, and the clinical and histological biointegration of the implanted material were assessed. h-ADASC adhered and survived when cultured in all PEA-based macroporous membranes. The addition of high hydrophilicity to PEA membranes decreased h-ADASC colonization in vitro. PEA-based copolymer containing 10% hydroxyethyl acrylate (PEA-HEA10) or 10% acrylic acid (PEA-AAc10) monomeric units showed the best cellular colonization rates. Collagen plus keratan sulfate-coated polymers demonstrated enhanced cellular colonization respect to fibronectin, collagen, or uncoated PEAs. In vivo implantation of membranes resulted in an extrusion rate of 72% for PEA, 50% for PEA-AAc10, but remarkably of 0% for PEA-HEA10. h-ADASC survival was demonstrated in all the membranes after 3 months follow-up. A slight reduction in the extrusion rate of h-ADASC colonized materials was observed. No significant differences between the groups with and without h-ADASC were detected respect to transparency or neovascularization. We propose PEA with low hydroxylation as a scaffold for the anchoring ring of future keratoprosthesis. PMID:24910285

  4. Acrylate Systemic Contact Dermatitis.

    PubMed

    Sauder, Maxwell B; Pratt, Melanie D

    2015-01-01

    Acrylates, the 2012 American Contact Dermatitis Society allergen of the year, are found in a range of products including the absorbent materials within feminine hygiene pads. When fully polymerized, acrylates are nonimmunogenic; however, if not completely cured, the monomers can be potent allergens.A 28-year-old woman is presented, who had her teeth varnished with Isodan (Septodont, Saint-Maur-des-Fossés, France) containing HEMA (2-hydroxyethyl methacrylate) with no initial reaction. Approximately 1 month later, the patient developed a genital dermatitis secondary to her feminine hygiene pads. The initial reaction resolved, but 5 months later, the patient developed a systemic contact dermatitis after receiving a second varnishing.The patient was dramatically patch test positive to many acrylates. This case demonstrates a reaction to likely unpolymerized acrylates within a feminine hygiene pad, as well as broad cross-reactivity or cosensitivity to acrylates, and possibly a systemic contact dermatitis with systemic re-exposure to unpolymerized acrylates. PMID:26367207

  5. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... polymerized copolymer of ethyl acrylate, methyl methacrylate, and methacrylic acid applied in emulsion form to... Glyceryl monostearate Methyl cellulose Mineral oil Paraffin wax Potassium hydroxide Potassium...

  6. Acrylic vessel cleaning tests

    SciTech Connect

    Earle, D.; Hahn, R.L.; Boger, J.; Bonvin, E.

    1997-02-26

    The acrylic vessel as constructed is dirty. The dirt includes blue tape, Al tape, grease pencil, gemak, the glue or residue form these tapes, finger prints and dust of an unknown composition but probably mostly acrylic dust. This dirt has to be removed and once removed, the vessel has to be kept clean or at least to be easily cleanable at some future stage when access becomes much more difficult. The authors report on the results of a series of tests designed: (a) to prepare typical dirty samples of acrylic; (b) to remove dirt stuck to the acrylic surface; and (c) to measure the optical quality and Th concentration after cleaning. Specifications of the vessel call for very low levels of Th which could come from tape residues, the grease pencil, or other sources of dirt. This report does not address the concerns of how to keep the vessel clean after an initial cleaning and during the removal of the scaffolding. Alconox is recommended as the cleaner of choice. This acrylic vessel will be used in the Sudbury Neutrino Observatory.

  7. Acrylic purification and coatings

    SciTech Connect

    Kuzniak, Marcin

    2011-04-27

    Radon (Rn) and its decay daughters are a well-known source of background in direct WIMP detection experiments, as either a Rn decay daughter or an alpha particle emitted from a thin inner surface layer of a detector could produce a WIMP-like signal. Different surface treatment and cleaning techniques have been employed in the past to remove this type of contamination. A new method of dealing with the problem has been proposed and used for a prototype acrylic DEAP-1 detector. Inner surfaces of the detector were coated with a layer of ultra pure acrylic, meant to shield the active volume from alphas and recoiling nuclei. An acrylic purification technique and two coating techniques are described: a solvent-borne (tested on DEAP-1) and solvent-less (being developed for the full scale DEAP-3600 detector).

  8. (E)-Ethyl 3-(2-fluoro-anilino)-2-(4-methoxy-phen-yl)acrylate.

    PubMed

    Zheng, Yi; Xiao, Zhu-Ping; Wang, Kai-Rui; Zhu, Hai-Liang

    2008-01-01

    The title compound, C(18)H(18)FNO(3), consists of three individually planar subunits, namely two substituted benzene rings and one amino-acrylate group. The dihedral angle between the two benzene rings is 47.48 (8)°. The amino-acrylate group forms dihedral angles of 57.95 (7) and 11.27 (6)° with the methoxy-phenyl and fluorophenyl rings, respectively. PMID:21201512

  9. Phase separation kinetics and morphology induced by photopolymerization of 2-hydroxyehyl methacrylate (HEMA) in poly(ethyl acrylate)/HEMA mixtures

    NASA Astrophysics Data System (ADS)

    Van-Pham, Dan-Thuy; Tran-Cong-Miyata, Qui

    2013-03-01

    Morphology and phase separation kinetics induced by polymerization of 2-hydroxyethyl methacrylate (HEMA) in a HEMA/poly(ethyl acrylate) (PEA) mixture were observed by laser scanning confocal microscope in the presence of lucirin TPO used as an initiator. The results were analyzed by 2D-Fourier transform (2D-FFT). The photopolymerization is driven by irradiation with visible light λ = 405 nm. The mixture exhibits the Trommsdorff-Norrish effect which is responsible for a drastic increase in the reaction rate during the irradiation process. The concentration fluctuations and the increase in the viscosity of the medium play an important role in promoting the reaction yield. PHEMA droplets were found to develop in the rhodamine-B-labeled poly(ethyl acrylate) (PEA-Rh) continuous matrix. The characteristic length of the morphology increases with increasing irradiation intensity, revealing the tool to control the morphology by varying the light intensity.

  10. 21 CFR 177.1010 - Acrylic and modified acrylic plastics, semirigid and rigid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Acrylic and modified acrylic plastics, semirigid... Acrylic and modified acrylic plastics, semirigid and rigid. Semirigid and rigid acrylic and modified acrylic plastics may be safely used as articles intended for use in contact with food, in accordance...

  11. 21 CFR 177.1010 - Acrylic and modified acrylic plastics, semirigid and rigid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylic and modified acrylic plastics, semirigid... Acrylic and modified acrylic plastics, semirigid and rigid. Semirigid and rigid acrylic and modified acrylic plastics may be safely used as articles intended for use in contact with food, in accordance...

  12. Preparation and optical properties of CdS nanoparticles dispersed in poly(2-(dimethylamino)ethyl methacrylate-co-acrylic acid) co-polymers

    NASA Astrophysics Data System (ADS)

    Trandafilović, L. V.; Djoković, V.; Bibić, N.; Georges, M. K.; Radhakrishnan, T.

    2008-03-01

    CdS/poly(2-(dimethylamino)ethyl methacrylate-co-acrylic acid) nanocomposites were prepared and characterized using structural, optical and thermal methods. Co-polymers used as the matrices were synthesized by radical polymerization of the co-monomers in different mol ratios (1:1, 2:1 and 1:2, DMAEMA:acrylic acid). The presence of the nanostructured CdS was confirmed by TEM analysis as well as by the shift of the onset of the optical absorption towards lower wavelengths. XRD spectra showed the cubic crystal phase of the obtained CdS nanoparticles. TGA measurements revealed improved thermal stability of the nanocomposite with respect to pure co-polymer matrix.

  13. Surface Properties of Poly[2-perfluorooctyl)ethyl acrylate] Deposited from Liquid CO2 High-Pressure Fee Meniscus Coating

    SciTech Connect

    Kim,J.; Efimenko, K.; Genzer, J.; Carbonell, R.

    2007-01-01

    The surface characteristics of poly[2-(perfluorooctyl)ethyl acrylate] (PFOEA) films deposited using a high-pressure free meniscus coating (hFMC) process with liquid CO{sub 2} (l-CO{sub 2}) as the coating solvent on 12.5 cm diameter silicon wafer substrates were investigated using contact angle measurements, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and near-edge X-ray adsorption fine structure (NEXAFS) spectroscopy. The results were compared with surface property measurements of PFOEA films deposited from 1,1,2-trichlorotrifluoroethane (Freon 113) under normal dip coating conditions at atmospheric pressure. NEXAFS measurements showed that perfluoroalkyl groups in the films from l-CO{sub 2} and Freon 113 were well-organized and oriented normal to the substrate at the air/polymer interface. AFM images and XPS measurements revealed that a terrace-like structure of the PFOEA film from l-CO{sub 2} resulted in carbonyl group exposure at the air/polymer interface. This leads to smaller contact angles on the films cast from l-CO{sub 2} relative to the specimens deposited from Freon 113. Annealing the films deposited from the solvents resulted in droplet formation on the surface due to dewetting. The critical surface tension ({gamma}{sub c}) after annealing the film prepared from Freon 113 increased from 6.5 to 8.5 mJ/m{sup 2}, whereas {gamma}{sub c} of the film deposited from l-CO{sub 2} decreased slightly from 9.7 to 8.9 mJ/m{sup 2}. We discuss how surface morphology changes before and after annealing play a role in the variation of {gamma}{sub c}.

  14. (Z)-Ethyl 3-(2,4-difluoro-anilino)-2-(4-methoxy-phen-yl)acrylate.

    PubMed

    Xiao, Zhu-Ping; Xiao, He-Ying

    2008-01-01

    The title compound, C(18)H(17)F(2)NO(3), consists of three individually planar subunits, namely two benzene rings and one amino-acrylate group. The amino-acrylate group forms dihedral angles of 5.92 (7) and 50.21 (6)° with the difluoro and methoxy benzene rings, respectively. The dihedral angle between the two benzene rings is 55.25 (7)°. The mol-ecules exhibit intra-molecular N-H⋯O and N-H⋯F inter-actions and form a three-dimensional network via inter-molecular C-H⋯O and C-H⋯π hydrogen bonds. PMID:21581343

  15. (E)-Ethyl 3-(4-fluoro-anilino)-2-(4-methoxy-phen-yl)acrylate.

    PubMed

    Zheng, Da-Gui; Xiao, Zhu-Ping

    2008-01-01

    In the title compound, C(18)H(18)FNO(3), the dihedral angles between the two benzene rings and the plane through the acrylate group and the fluoro-phenyl ring are 61.58 (8) and 13.33 (9)°, respectively. Mol-ecules are linked into ribbons through C-H⋯O and N-H⋯O hydrogen bonds, and further linked by C-H⋯π inter-actions, forming a three-dimensional network. PMID:21581424

  16. Preparation of Fe 3O 4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

    NASA Astrophysics Data System (ADS)

    Li, Xiaolong; Liu, Guoqiang; Yan, Wei; Chu, Paul K.; Yeung, Kelvin W. K.; Wu, Shuilin; Yi, Changfeng; Xu, Zushun

    2012-04-01

    Cationic magnetic polymer particles Fe3O4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe3O4, styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV-vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier.

  17. (Z)-Ethyl 3-(4-chloro­phen­yl)-2-cyano-3-(2,6-difluoro­benzamido)acrylate

    PubMed Central

    Dehua, Zhang; Xiaoyan, Zhang

    2008-01-01

    The title compound, C19H13ClF2N2O3, was prepared by the reaction of (Z)-ethyl 3-amino-3-(4-chloro­phen­yl)-2-cyano­acrylate and 2,6-difluoro­benzoyl chloride. The dihedral angle between the chloro­benzene and fluoro­benzene rings is 37.0 (1)°. The ethyl group is disordered over two positions [occupancies = 0.52 (2):0.48 (2)]. In addition to intra­molecular N—H⋯O and N—H⋯F hydrogen bonds, the crystal packing shows the mol­ecules to be connected by inter­molecular C—H⋯O and C—H⋯N hydrogen bonds. PMID:21581235

  18. Hydrophilic surface modification of acrylate-based biomaterials.

    PubMed

    Arnal-Pastor, M; Comín-Cebrián, S; Martínez-Ramos, C; Monleón Pradas, M; Vallés-Lluch, A

    2016-04-01

    Acrylic polymers have proved to be excellent with regard to cell adhesion, colonization and survival, in vitro and in vivo. Highly ordered and regular pore structures thereof can be produced with the help of polyamide templates, which are removed with nitric acid. This treatment converts a fraction of the ethyl acrylate side groups into acrylic acid, turning poly(ethyl acrylate) scaffolds into a more hydrophilic and pH-sensitive substrate, while its good biological performance remains intact. To quantify the extent of such a modification, and be able to characterize the degree of hydrophilicity of poly(ethyl acrylate), poly(ethyl acrylate) was treated with acid for different times (four, nine and 17 days), and compared with poly(acrylic acid) and a 90/10%wt. EA/AAc copolymer (P(EA-co-AAc)). The biological performance was also assessed for samples immersed in acid up to four days and the copolymer, and it was found that the incorporation of acidic units on the material surface was not prejudicial for cells. This surface modification of 3D porous hydrophobic scaffolds makes easier the wetting with culture medium and aqueous solutions in general, and thus represents an advantage in the manageability of the scaffolds. PMID:26767395

  19. Supramolecular assembly of (Z)-ethyl 2-cyano-3-((4-fluorophenyl)amino) acrylate, crystal structure, Hirshfeld surface analysis and DFT studies

    NASA Astrophysics Data System (ADS)

    Matos, Catiúcia R. M. O.; Vitorino, Letícia S.; de Oliveira, Pedro H. R.; de Souza, Maria Cecília B. V.; Cunha, Anna C.; Boechat, Fernanda da C. S.; Resende, Jackson A. L. C.; Carneiro, José Walkimar de M.; Ronconi, Célia M.

    2016-09-01

    A mixture of the E and Z isomers of ethyl 2-cyano-3-((4-fluorophenyl)amino) acrylate was synthesized and characterized by elemental analysis, attenuated total reflectance-Fourier transform infrared spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy. The structure of the Z isomer was determined by single crystal X-ray diffraction, which revealed a three-dimensional supramolecular network governed by Csbnd H⋯N, Csbnd H⋯O, and Csbnd H⋯F hydrogen bonds and π⋯π stacking interactions. The combination of these interactions plays an important role in stabilizing the self-assembly process and the molecular conformation. Hirshfeld surface analysis indicated the roles of the noncovalent interactions in the crystal packing, which were quantified by fingerprint plots and DFT calculations.

  20. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  1. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  2. Transparent acrylic enamel slide holograms

    NASA Astrophysics Data System (ADS)

    Ponce-Lee, E. L.; Olivares Pérez, A.; Ruiz-Limón, B.; Hernández-Garay, M. P.; Toxqui-López, S.

    2006-02-01

    We present holograms generated in a computer to an acrylic enamel slide (Comex (R)), getting phase holograms. The information in the mask is transferred to the material by temperature gradients generated by rubbing. The refraction index is transformed at each material point by the temperature changes, thus the film is recorded and developed by itself. this material can be used for soft lithography.

  3. Mixing It Up with Acrylics.

    ERIC Educational Resources Information Center

    Laird, Shirley

    1999-01-01

    Presents an art activity for fifth-grade students in which they learn about basic shapes and what happens when shapes overlap, draw seven overlapping geometric shapes, review the use of acrylic paint and mixing colors, and finally paint with primary colors. (CMK)

  4. Performance behavior of modified cellulosic fabrics using polyurethane acrylate copolymer.

    PubMed

    Zuber, Mohammad; Shah, Sayyed Asim Ali; Jamil, Tahir; Asghar, Muhammad Irfan

    2014-06-01

    The surface of the cellulosic fabrics was modified using self-prepared emulsions of polyurethane acrylate copolymers (PUACs). PUACs were prepared by varying the molecular weight of polycaprolactone diol (PCL). The PCL was reacted with isophorone diisocyanate (IPDI) and chain was extended with 2-hydroxy ethyl acrylate (HEA) to form vinyl terminated polyurethane (VTPU) preploymer. The VTPU was further co-polymerized through free radical polymerization with butyl acrylate in different proportions. The FT-IR spectra of monomers, prepolymers and copolymers assured the formation of proposed PUACs structure. The various concentrations of prepared PUACs were applied onto the different fabric samples using dip-padding techniques. The results revealed that the application of polyurethane butyl acrylate copolymer showed a pronounced effect on the tear strength and pilling resistance of the treated fabrics. PMID:24661889

  5. Acrylic esters in radiation polymerization

    SciTech Connect

    Fomina, N.V.; Khoromskaya, V.A.; Shiryaeva, G.V.

    1988-03-01

    The radiation behavior of (meth)acrylic esters of varying structure was studied. It was shown that in radiation polymerization, in contrast to thermal polymerization, the structure of the ester part can significantly affect the reaction rate and capacity for polymerization in the presence of oxygen. The experimental data are explained from the point of view of consideration of nonvalence effects of the substitutent on the reactivity of the double bond.

  6. A method for preparing sodium acrylate-d3, a useful and stable precursor for deuterated acrylic monomers

    SciTech Connect

    Yang, Jun; Hong, Kunlun; Bonnesen, Peter V

    2011-01-01

    A convenient and economical method for converting propiolic acid to sodium acrylate-d3 is described. Successive D/H exchange of the alkyne proton of sodium propiolate (prepared from propiolic acid) using D2O affords sodium propiolate-d having up to 99 atom% D. Sodium propiolate-d can be partially reduced to sodium acrylate-d3 with 90% conversion and 89% yield, using D2 and the Lindlar catalyst with control of reaction parameters to maximize conversion while minimizing over reduction.

  7. Experimental and DFT study on a newly synthesized ethyl 2-cyano-3-[5-(phenyl-hydrazonomethyl)-1H-pyrrol-2-yl]-acrylate

    NASA Astrophysics Data System (ADS)

    Rawat, Poonam; Singh, R. N.

    2015-02-01

    A newly synthesized ethyl 2-cyano-3-[5-(phenyl-hydrazonomethyl)-1H-pyrrol-2-yl]-acrylate (ECPHPA) has been characterized by experimental measurements. The theoretically calculated results are in accordance with the experimental studies. All calculations have been performed using B3LY/6-31G(d,p) basis set. The oscillatory strength (f) and wavelength of various electronic excitations show π → π∗ nature of transitions. Natural bond orbital (NBO) analysis shows intramolecular conjugative/hyperconjugative interactions within the studied molecule. The result of hydrogen bonding is obvious in 1H NMR, FT-IR and NBO analyses as down field chemical shift, vibrational red shift and π1(C8sbnd N9) → σ∗(N1sbnd H24) interaction, respectively. Global electrophilicity index (ω = 4.80 eV) shows that ECPHPA is a strong electrophile and local reactivity descriptors indicate have reactive sites within molecule and undergo for the formation of various heterocyclic compounds. The first hyperpolarizability (β0) computed found to be 35.76 × 10-30 esu, evaluate the suitability of compound for non-linear optical (NLO) response.

  8. Determination of conformational and spectroscopic features of ethyl trans-alfa-cyano-3-indole-acrylate compound: An experimental and quantum chemical study

    NASA Astrophysics Data System (ADS)

    Cinar, Mehmet; Karabacak, Mehmet

    2013-03-01

    The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and non-linear optical properties of ethyl trans-alfa-cyano-3-indole-acrylate (C14H12N2O2) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman in the range of 4000-400 cm-1 and 4000-10 cm-1, respectively. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The 1H, 13C and DEPT NMR spectra were recorded in DMSO solution, and gauge-invariant atomic orbitals (GIAO) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were recorded in the range of 200-800 nm in various solvents of different polarity (acetone, benzene, chlorobenzene, chloroform, DMSO, ethanol, methanol and toluene). Solvent effects were calculated using TD-DFT and CIS method. To investigate the non-linear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations.

  9. Determination of conformational and spectroscopic features of ethyl trans-alfa-cyano-3-indole-acrylate compound: an experimental and quantum chemical study.

    PubMed

    Cinar, Mehmet; Karabacak, Mehmet

    2013-03-01

    The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and non-linear optical properties of ethyl trans-alfa-cyano-3-indole-acrylate (C(14)H(12)N(2)O(2)) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman in the range of 4000-400 cm(-1) and 4000-10 cm(-1), respectively. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The (1)H, (13)C and DEPT NMR spectra were recorded in DMSO solution, and gauge-invariant atomic orbitals (GIAO) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were recorded in the range of 200-800 nm in various solvents of different polarity (acetone, benzene, chlorobenzene, chloroform, DMSO, ethanol, methanol and toluene). Solvent effects were calculated using TD-DFT and CIS method. To investigate the non-linear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. PMID:23274474

  10. Nanoporous nonwoven fibril-like morphology by cooperative self-assembly of poly(ethylene oxide)-block-poly(ethyl acrylate)-block-polystyrene and phenolic resin.

    PubMed

    Deng, Guodong; Qiang, Zhe; Lecorchick, Willis; Cavicchi, Kevin A; Vogt, Bryan D

    2014-03-11

    Cooperative self-assembly of block copolymers with (in)organic precursors effectively generates ordered nanoporous films, but the porosity is typically limited by the need for a continuous (in)organic phase. Here, a network of homogeneous fibrous nanostructures (≈20 nm diameter cylinders) having high porosity (≈ 60%) is fabricated by cooperative self-assembly of a phenolic resin oligomer (resol) with a novel, nonfrustrated, ABC amphiphilic triblock copolymer template, poly(ethylene oxide)-block-poly(ethyl acrylate)-block-polystyrene (PEO-b-PEA-b-PS), via a thermally induced self-assembly process. Due to the high glass transition temperature (Tg) of the PS segments, the self-assembly behavior is kinetically hindered as a result of competing effects associated with the ordering of the self-assembled system and the cross-linking of resol that suppresses segmental mobility. The balance in these competing processes reproducibly yields a disordered fibril network with a uniform fibril diameter. This nonequilibrium morphology is dependent on the PEO-b-PEA-b-PS to resol ratio with an evolution from a relatively open fibrous structure to an apparent poorly ordered mixed lamellae-cylinder morphology. Pyrolysis of these former films at elevated temperatures yields a highly porous carbon film with the fibril morphology preserved through the carbonization process. These results illustrate a simple method to fabricate thin films and coatings with a well-defined fiber network that could be promising materials for energy and separation applications. PMID:24548298

  11. 40 CFR 721.405 - Polyether acrylate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.405 Polyether acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a polyether acrylate (PMN P-95-666) is subject...

  12. 40 CFR 721.405 - Polyether acrylate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.405 Polyether acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a polyether acrylate (PMN P-95-666) is subject...

  13. Radiopurity measurement of acrylic for DEAP-3600

    SciTech Connect

    Nantais, C. M.; Boulay, M. G.; Cleveland, B. T.

    2013-08-08

    The spherical acrylic vessel that contains the liquid argon target is the most critical detector component in the DEAP-3600 dark matter experiment. Alpha decays near the inner surface of the acrylic vessel are one of the main sources of background in the detector. A fraction of the alpha energy, or the recoiling nucleus from the alpha decay, could misreconstruct in the fiducial volume and result in a false candidate dark matter event. Acrylic has low levels of inherent contamination from {sup 238}U and {sup 232}Th. Another background of particular concern is diffusion of {sup 222}Rn during manufacturing, leading to {sup 210}Pb contamination. The maximum acceptable concentrations in the DEAP-3600 acrylic vessel are ppt levels of {sup 238}U and {sup 232}Th equivalent, and 10{sup −8} ppt {sup 210}Pb. The impurities in the bulk acrylic will be measured by vaporizing a large quantity of acrylic and counting the concentrated residue with ultra-low background HPGe detectors and a low background alpha spectrometer. An overview of the acrylic assay technique is presented.

  14. 21 CFR 573.120 - Acrylamide-acrylic acid resin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573... Food Additive Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin... acrylamide with partial hydrolysis, or by copolymerization of acrylamide and acrylic acid with the...

  15. 21 CFR 573.120 - Acrylamide-acrylic acid resin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573... Food Additive Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin... acrylamide with partial hydrolysis, or by copolymerization of acrylamide and acrylic acid with the...

  16. 21 CFR 573.120 - Acrylamide-acrylic acid resin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573... Food Additive Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin... acrylamide with partial hydrolysis, or by copolymerization of acrylamide and acrylic acid with the...

  17. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Acrylamide-acrylic acid resins. 176.110 Section... Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be...) Acrylamide-acrylic acid resins are produced by the polymerization of acrylamide with partial hydrolysis or...

  18. 21 CFR 573.120 - Acrylamide-acrylic acid resin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573... Food Additive Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin... acrylamide with partial hydrolysis, or by copolymerization of acrylamide and acrylic acid with the...

  19. 21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ethylene-acrylic acid copolymers. 177.1310 Section... Use Food Contact Surfaces § 177.1310 Ethylene-acrylic acid copolymers. The ethylene-acrylic acid... for use in contact with food subject to the provisions of this section. (a) The ethylene-acrylic...

  20. Preparation and properties of UV curable acrylic PSA by vinyl bonded graphene oxide

    NASA Astrophysics Data System (ADS)

    Pang, Beili; Ryu, Chong-Min; Jin, Xin; Kim, Hyung-Il

    2013-11-01

    Acrylic pressure sensitive adhesives (PSAs) with higher thermal stability for thin wafer handling were successfully prepared by forming composite with the graphene oxide (GO) nanoparticles modified to have vinyl groups via subsequent reaction with isophorone diisocyanate and 2-hydroxyethyl methacrylate. The acrylic copolymer was synthesized as a base resin for PSAs by solution radical polymerization of ethyl acrylate, 2-ethylhexyl acrylate, and acrylic acid followed by further modification with GMA to have the vinyl groups available for UV curing. The peel strength of PSA decreased with the increase of gel content which was dependent on both modified GO content and UV dose. Thermal stability of UV-cured PSA was improved noticeably with increasing the modified GO content mainly due to the strong and extensive interfacial bonding formed between the acrylic copolymer matrix and GO fillers

  1. Enzyme-catalyzed synthesis of saccharide acrylate monomers from nonedible biomass.

    PubMed

    Kloosterman, Wouter M J; Brouwer, Sander G M; Loos, Katja

    2014-08-01

    Various cellulase preparations were found to catalyze the transglycosidation between cotton linters and 2-hydroxyethyl acrylate. The conversion and enzyme activity were found to be optimal in reaction mixtures that contained 5 vol % of the acrylate. The structures of the products were revealed by using TLC and (1) H and (13) C NMR spectroscopy. The enzyme-catalyzed reaction resulted in two products. The minor product originated from transglycosidation to hemicellulose and was found to be 2-(β-xylosyloxy)-ethyl acrylate. The major product was identified as 2-(β-glucosyloxy)-ethyl acrylate and the yield of the product was 5 wt % based on the amount of consumed cellulose. Glycosidation products with oligosaccharide moieties could not be detected in the reaction mixture. This result can be explained by the hydrolytic activities of the used cellulase preparation. Cellulase from Trichoderma reesei was found to possess, in addition to endoglucanase activity, cellobiosidase and β-glucosidase activities. Five other cellulase preparations from different origins were tested as well for catalysis of oligosaccharide acrylate synthesis. For most cellulase preparations the major transglycosidation product appeared to be 2-(β-glucosyloxy)-ethyl acrylate. Nevertheless, the endo-β-(1,4)-glucanase from Trichoderma longibrachiatum was found to catalyze the synthesis of 2-(β-cellobiosyloxy)-ethyl acrylate. Unlike the other cellulase preparations, endo-β-(1,4)-glucanase from T. longibrachiatum showed no detectable β-glucosidase activity and therefore oligosaccharide acrylate monomers were not further hydrolyzed into the monosaccharide acrylate 2-(β-glucosyloxy)-ethyl acrylate. PMID:24866837

  2. Occupational respiratory disease caused by acrylates.

    PubMed

    Savonius, B; Keskinen, H; Tuppurainen, M; Kanerva, L

    1993-05-01

    Acrylates are compounds used in a variety of industrial fields and their use is increasing. They have many features which make them superior to formerly used chemicals, regarding both their industrial use and their possible health effects. Contact sensitization is, however, one of their well known adverse health effects but they may also cause respiratory symptoms. We report on 18 cases of respiratory disease, mainly asthma, caused by different acrylates, 10 cases caused by cyanoacrylates, four by methacrylates and two cases by other acrylates. PMID:8334539

  3. UV curing of nanoparticle reinforced acrylates

    NASA Astrophysics Data System (ADS)

    Bauer, F.; Flyunt, R.; Czihal, K.; Ernst, H.; Naumov, S.; Buchmeiser, M. R.

    2007-12-01

    To improve the surface hardness of radiation cured acrylate coatings, both silica nanoparticles and alumina particles with a few microns in size have been embedded into acrylate formulations. Regular mixing of nanoparticles into acrylate formulations, however, leads to highly viscous solutions inappropriate for coating procedures. The incompatibility of inorganic fillers and organic polymers can be avoided by surface modification of nanoparticles using trialkoxysilanes, which provide an interface between the two dissimilar materials. Nanoparticles modified by methacryloxypropyltrimethoxysilane (MEMO) and vinyltrimethoxysilane (VTMO), both having polymerisation-active groups, may be crosslinked with the acrylate resin. UV curing of the nanocomposites revealed an unexpected lower reactivity of the vinyl groups of VTMO modified silica compared to MEMO grafted on silica. For VTMO modification, DFT calculations showed a decrease of Mulliken atomic charge for the olefinic carbons pointing to a lower reactivity. For UV cured nano/microhybrid composites, a significant improvement of abrasion resistance was obtained.

  4. Gel time of calcium acrylate grouting material.

    PubMed

    Han, Tong-Chun

    2004-08-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerization reaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reaction kinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time of calcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and an example is provided to verify the proposed formula. PMID:15236477

  5. The acute aquatic toxicity of a series of acrylate and methacrylate esters

    SciTech Connect

    Staples, C.A.; McLaughlin, J.E.; Hamilton, J.D.

    1994-12-31

    Acute aquatic toxicity data for several acrylate and methacrylate esters were reviewed. Acrylates included acrylic acid, ethyl-, and butyl-acrylate. Methacrylates included methacrylic acid, methyl-, and butyl-methacrylate. Tests were 48 hr or 96 hr standard flow through (invertebrates and fish) assays (measured exposure concentrations). These data are currently used in a risk assessment of acrylate/methacrylate environmental safety. Algal growth (Selanastrum capricomutum) 96 hr EC{sub 50}s were 0.17 mg/L (NOEC < 0.13 mg/L) for acrylic acid, 11.0 mg/L (NOEC < 6.5 mg/L) for ethyl acrylate, and 5.2 mg/L (NOEC < 3.8 mg/L) for butyl acrylate. Invertebrate (Daphnia magna) 48 hr LC{sub 50}s were 95.0 mg/L (NOEC 23.0 mg/L) for acrylic acid, 7.9 mg/L (NOEC 3.4 mg/L) for ethyl acrylate, and 8.2 mg/L (NOEC 2.4 mg/L) for butyl acrylate. Rainbow trout (Oncorhynchus mykiss) 96 hr LC{sub 50}s were 27.0 mg/L (NOEC 6.3 mg/L) for acrylic acid, 4.6 mg/L (NOEC 0.78 mg/L) for ethyl acrylate, and 5.2 mg/L (NOEC 3.8 mg/L) for butyl acrylate. Algae 96 hr EC{sub 50}s were 0.59 mg/L (NOEC 0.38 mg/L) for methacrylic acid, 170.0 mg/L (NOEC 100.0 mg/L) for methyl methacrylate, and 130.0 mg/L for butyl methacrylate. Daphnia magna 48 hr LC{sub 50}s were > 130.0 mg/L (NOEC 130.0 mg/L) for methacrylic acid, 69.0 mg/L (NOEC 48.0 mg/L) for methyl methacrylate, and 32.0 mg/L (NOEC 23.0 mg/L) for butyl methacrylate. Trout 96 hr LC{sub 50}s were 85.0 mg/L (NOEC 12.0 mg/L) for methacrylic acid and > 79.0 mg/L (NOEC 40.0 mg/L) for methyl methacrylate. The fathead minnow (Pimephales promelas) 96 hr LC{sub 50} was 11.0 mg/L for butyl methacrylate.

  6. Allergic contact dermatitis to acrylates in disposable blue diathermy pads.

    PubMed Central

    Sidhu, S. K.; Shaw, S.

    1999-01-01

    We report 2 cases of elicitation of allergic contact dermatitis to acrylates from disposable blue diathermy pads used on patients who underwent routine surgery. Their reactions were severe, and took approximately 5 weeks to resolve. Both patients gave a prior history of finger tip dermatitis following the use of artificial sculptured acrylic nails, which is a common, but poorly reported, cause of acrylate allergy. Patch testing subsequently confirmed allergies to multiple acrylates present in both the conducting gel of disposable blue diathermy pads, and artificial sculptured acrylic nails. We advocate careful history taking prior to surgery to avoid unnecessary exposure to acrylates in patients already sensitized. Images Figure 1 Figure 2 PMID:10364952

  7. SOURCE ASSESSMENT: ACRYLIC ACID MANUFACTURE; STATE-OF-THE-ART

    EPA Science Inventory

    This report summarizes data on air emissions from the production of acrylic acid. Hydrocarbons, carbon monoxide, and nitrogen oxide are emitted from various operations. Hydrocarbon emissions consist of acetaldehyde, acetic acid, acetone acrolein, acrylic acid, benzene, phenol, pr...

  8. PERMEATION OF MULTIFUNCTIONAL ACRYLATES THROUGH THREE PROTECTIVE CLOTHING MATERIALS

    EPA Science Inventory

    Permeation tests were conducted with trimethylolpropane triacrylate TMPTA), 1,6-hexanediol diacrylate (HDDA), and two mixtures of 1,6-hexanediol diacrylate with 2-ethylhexyl acrylate (EHA) to better understand the permeation behavior of multifunctional acrylate compounds. he test...

  9. Analysis of emulsion stability in acrylic dispersions

    NASA Astrophysics Data System (ADS)

    Ahuja, Suresh

    2012-02-01

    Emulsions either micro or nano permit transport or solubilization of hydrophobic substances within a water-based phase. Different methods have been introduced at laboratory and industrial scales: mechanical stirring, high-pressure homogenization, or ultrasonics. In digital imaging, toners may be formed by aggregating a colorant with a latex polymer formed by batch or semi-continuous emulsion polymerization. Latex emulsions are prepared by making a monomer emulsion with monomer like Beta-carboxy ethyl acrylate (β-CEA) and stirring at high speed with an anionic surfactant like branched sodium dodecyl benzene sulfonates , aqueous solution until an emulsion is formed. Initiator for emulsion polymerization is 2-2'- azobis isobutyramide dehydrate with chain transfer agent are used to make the latex. If the latex emulsion is unstable, the resulting latexes produce a toner with larger particle size, broader particle size distribution with relatively higher latex sedimentation, and broader molecular weight distribution. Oswald ripening and coalescence cause droplet size to increase and can result in destabilization of emulsions. Shear thinning and elasticity of emulsions are applied to determine emulsion stability.

  10. Terpolymers of ethyl acrylate/methacrylic acid/unsaturated acid ester of alcohols and acids as anti-settling agents in coal water slurries

    SciTech Connect

    Savoly, A.; Villa, J.L.; Grinstein, R.H.; Nachfolger, S.J.

    1988-05-17

    This patent describes a pumpable stabilized coal water slurry, having a coal content of at least about 50% by weight wherein at least 80% of the coal particles are about 200 mesh or finer, containing from about 0.01% to about 1% by weight of the slurry of a water soluble terpolymer of ethylacrylate (A), metacrylic acid (B) and a third monomer (C) selected from the group consisting of an unsaturated carboxylic acid ester of an alcohol and an ethoxylated carboxylic acid. The unsaturated carboxylic acid is a mono- or di- basic unsaturated carboxylic acid of 3 to 10 carbon atoms selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, fumaric acid, and maleic acid.

  11. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylate ester copolymer coating. 175.210 Section... COATINGS Substances for Use as Components of Coatings § 175.210 Acrylate ester copolymer coating. Acrylate ester copolymer coating may safely be used as a food-contact surface of articles intended for...

  12. 40 CFR 721.484 - Fluorinated acrylic copolymer (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Fluorinated acrylic copolymer (generic... Specific Chemical Substances § 721.484 Fluorinated acrylic copolymer (generic name). (a) Chemical substance... fluorinated acrylic copolymer (PMN P-95-1208) is subject to reporting under this section for the...

  13. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  14. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  15. 40 CFR 721.484 - Fluorinated acrylic copolymer (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Fluorinated acrylic copolymer (generic... Specific Chemical Substances § 721.484 Fluorinated acrylic copolymer (generic name). (a) Chemical substance... fluorinated acrylic copolymer (PMN P-95-1208) is subject to reporting under this section for the...

  16. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  17. 21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethylene-acrylic acid copolymers. 177.1310 Section... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1310 Ethylene-acrylic acid copolymers. The ethylene-acrylic acid copolymers identified in paragraph (a) of this section may be...

  18. 21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene-acrylic acid copolymers. 177.1310 Section... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1310 Ethylene-acrylic acid copolymers. The ethylene-acrylic acid copolymers identified in paragraph (a) of this section may be...

  19. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylamide-acrylic acid resins. 176.110 Section 176... Substances for Use Only as Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of articles intended for use in...

  20. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Acrylamide-acrylic acid resins. 176.110 Section... Substances for Use Only as Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of articles intended for use in...

  1. 21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-acrylic acid copolymers. 177.1310 Section... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1310 Ethylene-acrylic acid copolymers. The ethylene-acrylic acid copolymers identified in paragraph (a) of this section may be...

  2. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Acrylamide-acrylic acid resins. 176.110 Section... Substances for Use Only as Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of articles intended for use in...

  3. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Acrylamide-acrylic acid resins. 176.110 Section... Substances for Use Only as Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of articles intended for use in...

  4. 21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene-acrylic acid copolymers. 177.1310 Section... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1310 Ethylene-acrylic acid copolymers. The ethylene-acrylic acid copolymers identified in paragraph (a) of this section may be...

  5. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate...

  6. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate...

  7. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate...

  8. 40 CFR 721.10528 - Modified fluorinated acrylates (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Modified fluorinated acrylates... Specific Chemical Substances § 721.10528 Modified fluorinated acrylates (generic). (a) Chemical substances... modified fluorinated acrylates (PMNs P-12-30, P-12-31, and P-12-32) are subject to reporting under...

  9. 40 CFR 721.10528 - Modified fluorinated acrylates (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Modified fluorinated acrylates... Specific Chemical Substances § 721.10528 Modified fluorinated acrylates (generic). (a) Chemical substances... modified fluorinated acrylates (PMNs P-12-30, P-12-31, and P-12-32) are subject to reporting under...

  10. 40 CFR 721.5325 - Nickel acrylate complex.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Nickel acrylate complex. 721.5325... Substances § 721.5325 Nickel acrylate complex. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance nickel acrylate complex (PMN P-85-1034) is subject to reporting...

  11. 40 CFR 721.5325 - Nickel acrylate complex.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Nickel acrylate complex. 721.5325... Substances § 721.5325 Nickel acrylate complex. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance nickel acrylate complex (PMN P-85-1034) is subject to reporting...

  12. 40 CFR 721.5325 - Nickel acrylate complex.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Nickel acrylate complex. 721.5325... Substances § 721.5325 Nickel acrylate complex. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance nickel acrylate complex (PMN P-85-1034) is subject to reporting...

  13. 40 CFR 721.5325 - Nickel acrylate complex.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Nickel acrylate complex. 721.5325... Substances § 721.5325 Nickel acrylate complex. Link to an amendment published at 79 FR 34637, June 18, 2014... nickel acrylate complex (PMN P-85-1034) is subject to reporting under this section for the...

  14. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate...

  15. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  16. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  17. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate...

  18. 40 CFR 721.405 - Polyether acrylate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polyether acrylate. 721.405 Section 721.405 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL...) The significant new uses are: (i) Release to water. Requirements as specified in § 721.90 (a)(1),...

  19. Worn down nails after acrylic nail removal.

    PubMed

    Wu, Timothy P; Morrison, Brian W; Tosti, Antonella

    2015-01-01

    Worn-down nail syndrome is a nail disorder characterized by thinning of the distal nail plate caused by repetitive chemical or mechanical trauma. We present a previously undescribed source of worn-down nail syndrome caused by trauma from nail filing after acrylic nail removal. PMID:25612131

  20. Acrylic Tanks for Stunning Chemical Demonstrations

    ERIC Educational Resources Information Center

    Mirholm, Alexander; Ellervik, Ulf

    2009-01-01

    We describe the use of acrylic tanks (400 x 450 x 27 mm) for visualization of chemical demonstrations in aqueous solutions. Examples of well-suited demonstrations are oscillating reactions, pH indicators, photochemical reduction of Lauth's violet, and chemoluminiscent reactions. (Contains 1 figure.)

  1. Structure-toxicity relationships of acrylic monomers.

    PubMed Central

    Autian, J

    1975-01-01

    Esters of acrylic acid, in particular methyl methacrylate, have wide applications in a number of industrial and consumer products, forming very desirable nonbreakable glass-like materials. In dentistry, the monomers are used to prepare dentures and a variety of filling and coating materials for the teeth. Surgeons utilize the monomers to prepare a cement which helps anchor prosthetic devices to bone. Special types of acrylic monomers such as the cyano derivatives have found a useful application as adhesive materials. Most of the acrylic acid esters are volatile substances and can produce various levels of toxicity if inhaled. A large number of workers thus exposed to the vapors of these esters can develop clinical symptoms and signs of toxicity. This paper will discuss the toxicity of a large number of acrylic esters, and will attempt to show structure-activity relationships where such data are available. General comments will also be made as to the potential health hazards this variety of esters may present to selected segments of the population. PMID:1175551

  2. UV-curable acrylated coating from epoxidized palm oil

    NASA Astrophysics Data System (ADS)

    Rahman, Nurliyana Abd; Badri, Khairiah Haji; Salleh, Nik Ghazali Nik

    2014-09-01

    The properties of coating film prepared from the incorporation of acrylated palm oil (EPOLA) in commercial epoxy acrylate have been studied. A series of different amount of EPOLA was mixed with commercial epoxy acrylate. The blended acrylates passed through UV light to produce a non-tacky film. The conversion of acrylate double bond was monitored by FTIR. The effect of EPOLA concentration onto coated films were investigated by determination of the pendulum hardness and gel content. The higher the amount of EPOLA, the lower the pendulum hardness and the gel content but to a level acceptable for usage in the high-end applications.

  3. Toward pH-responsive coating materials--high-throughput study of (meth)acrylic copolymers.

    PubMed

    Krieg, Andreas; Arici, Elif; Windhab, Norbert; Schattka, Jan Hendrik; Schubert, Stephanie; Schubert, Ulrich S

    2014-08-11

    The release behavior of a model compound (β-naphthol orange) encapsulated in (meth)acrylate-based statistical copolymers under different environmental conditions was investigated. From monomers of varying polarity (methyl acrylate, ethyl acrylate, tert-butyl acrylate, 2-ethylhexyl methacrylate, and benzyl methacrylate) in combination with methacrylic acid, five polymer series were synthesized by free radical polymerization. The pH-dependent release kinetics were investigated via UV-vis spectroscopy at pH 1.2 and 6.8, simulating physiological conditions in the stomach and intestines. Furthermore, the influence of different ethanol contents (0 and 40 vol %) in the acidic medium was investigated. The whole approach was designed to meet the requirements of a high-throughput experimentation workflow. PMID:24964068

  4. 'Weightless' acrylic painting by Jack Kroehnke

    NASA Technical Reports Server (NTRS)

    1987-01-01

    'Weightless' acrylic painting by Jack Kroehnke depicts STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) David C. Hilmers participating in extravehicular activity (EVA) simulation in JSC Weightless Environment Training Facility (WETF) Bldg 29. In the payload bay (PLB) mockup, Hilmers, wearing extravehicular mobility unit (EMU), holds onto the mission-peculiar equipment support structure in foreground while SCUBA-equipped diver monitors activity overhead and camera operator records EVA procedures. Copyrighted art work for use by NASA.

  5. Performance comparison of acrylic and thiol-acrylic resins in two-photon polymerization.

    PubMed

    Jiang, Lijia; Xiong, Wei; Zhou, Yushen; Liu, Ying; Huang, Xi; Li, Dawei; Baldacchini, Tommaso; Jiang, Lan; Lu, Yongfeng

    2016-06-13

    Microfabrication by two-photon polymerization is investigated using resins based on thiol-ene chemistry. In particular, resins containing different amounts of a tetrafunctional acrylic monomer and a tetrafunctional thiol molecule are used to create complex microstructures. We observe the enhancement of several characteristics of two-photon polymerization when using thiol-acrylic resins. Specifically, microfabrication is carried out using higher writing velocities and it produces stronger polymeric microstructures. Furthermore, the amount of shrinkage typically observed in the production of three-dimensional microstructures is reduced also. By means of microspectrometry, we confirm that the thiol-acrylate mixture in TPP resins promote monomer conversion inducing a higher degree of cross-linked network formation. PMID:27410383

  6. UV-curable polyurethane acrylate coatings with different acrylate monomers as reactive diluents

    SciTech Connect

    Nabeth, B.; Gerard, J.F.; Pascault, J.P.

    1995-12-01

    Two series of UV-curable polyurethane acrylate (PUA) based on polycaprolactone (PCL), tetraxylylene diisocyanate (TMXDI), and hydroxyethyl acrylate (HEA) or hydroxyethyl methacrylate (HEMA) were studied. These ones were considered with different acrylates as reactive diluents. The effect of the chemical nature and functionality of the reactive diluents on the thermal and dynamic mechanical properties (DMS) was investigated. From a thermodynamic point of view, the PUA seem to display a one phase structure by DMS. Nevertheless, the statistic heterogeneities due to the use of three monomers or more can explain the Tg values and the mechanical relaxations of the PUA. The Tg-onset of the PUA is slightly influenced by the nature of the reactive diluents but is dependent on the Tg of the oligomer confirming the description of the structure using a clusters model. The same conclusions could be done from the dynamic mechanical spectra of the PUA sandwiched and UV-cured between two glass plates.

  7. Palladium (II) catalyized polymerization of norbornene and acrylates

    DOEpatents

    Sen, Ayusman; Kacker, Smita; Hennis, April; Polley, Jennifer D.

    2000-08-29

    Homopolymers or copolymers of acrylates, homopolymers or copolymers of norbornenes, and copolymers of acrylates with norbornenes, may be prepared by contacting acrylate and/or norbornene monomer reactant under polymerization conditions and in the presence of a solvent with a catalyst system consisting essentially of a Pd(II) dimer component having the formula: [(L)Pd(R)(X)].sub.2, where L is a monodentate phosphorus or nitrogen ligand, X is an anionic group, and R is an alkyl or aryl group.

  8. Palladium (Ii) Catalyzed Polymerization Of Norbornene And Acrylates

    DOEpatents

    Sen, Ayusman; Kacker, Smita; Hennis, April; Polley, Jennifer D.

    2001-10-09

    Homopolymers or copolymers of acrylates, homopolymers or copolymers of norbornenes, and copolymers of acrylates with norbornenes, may be prepared by contacting acrylate and/or norbornene monomer reactant under polymerization conditions and in the presence of a solvent with a catalyst system consisting essentially of a Pd(II) dimer component having the formula: where L is a monodentate phosphorus or nitrogen ligand, X is an anionic group, and R is an alkyl or aryl group.

  9. Severe Onychodystrophy due to Allergic Contact Dermatitis from Acrylic Nails

    PubMed Central

    Mattos Simoes Mendonca, Marcela; LaSenna, Charlotte; Tosti, Antonella

    2015-01-01

    Acrylic nails, including sculptured nails and the new ultraviolet-curable gel polish lacquers, have been associated with allergic contact dermatitis (ACD). We report 2 cases of ACD to acrylic nails with severe onychodystrophy and psoriasiform changes including onycholysis and subungual hyperkeratosis. In both cases, the patients did not realize the association between the use of acrylate-based manicures and nail changes. One patient had been previously misdiagnosed and treated unsuccessfully for nail psoriasis. The informed clinician should elicit a history of acrylic manicure in patients with these nail changes, especially in cases of suspected nail psoriasis refractory to treatment. Patch testing is a useful tool in confirming diagnosis. PMID:27170940

  10. Responsive Copolymer Brushes of Poly[(2-(Methacryloyloxy)Ethyl) Trimethylammonium Chloride] (PMETAC) and Poly((1) H,(1) H,(2) H,(2) H-Perfluorodecyl acrylate) (PPFDA) to Modulate Surface Wetting Properties.

    PubMed

    Politakos, Nikolaos; Azinas, Stavros; Moya, Sergio Enrique

    2016-04-01

    Polymer brushes have a large potential for controlling properties such as surface lubrication or wetting through facile functionalization. Polymer chemistry, chain density, and length impact on the wetting properties of brushes. This study explores the use of diblock copolymer brushes with different block length and spatial arrangement of the blocks to tune surface wettability. Block copolymer brushes of the polyelectrolyte [2-(methacryloyloxy)ethyl] trimethylammonium chloride (PMETAC) with a contact angle of 17° and a hydrophobic block of (1) H, (1) H, (2) H, (2) H-perfluorodecyl Acrylate (PPFDA) with a contact angle of 130° are synthesized by RAFT polymerization. By changing the sequence of polymerization either block is synthesized as top or bottom block. By varying the concentration of initiator the length of the blocks is varied. Contact angle values with intermediate values between 17° and 130° are measured. In addition, by changing solvent pH and in presence of a different salt the contact angle of the copolymer brushes can be fine tuned. Brushes are characterized by atomic force microscopy, Raman confocal microscopy, and X-ray photoelectron spectroscopy. PMID:26872001

  11. Kinetics of the gas-phase reaction between ozone and three unsaturated oxygenated compounds: Ethyl 3,3-dimethyl acrylate, 2-methyl-2-pentenal and 6-methyl-5-hepten-2-one at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Gaona Colmán, Elizabeth; Blanco, María B.; Barnes, Ian; Teruel, Mariano A.

    2015-05-01

    Rate coefficients for the gas-phase reactions of O3 molecules with three unsaturated oxygenated compounds have been determined using the relative kinetic technique in an environmental chamber with FTIR detection of the reactants at (298 ± 2) K in 760 Torr total pressure of synthetic air. The following rate coefficients (in units of 10-17 cm3 molecule-1 s-1) were determined: ethyl 3,3-dimethyl acrylate (0.82 ± 0.19), 2-methyl-2-pentenal (0.71 ± 0.16) and 6-methyl-5-hepten-2-one (26 ± 7). The different reactivity of the unsaturated oxygenated compounds toward O3 is discussed in terms of their chemical structure. In addition, a correlation between the reactivity of structurally different unsaturated compounds (alkenes and unsaturated oxygenated VOCs, such as ethers, esters, aldehydes, ketones and alcohols) toward O3 molecules and the HOMO (Highest Occupied Molecular Orbital) of the compounds is presented. Using the kinetic parameters determined in this work, residence times of these unsaturated compounds in the atmosphere with respect to reaction with O3 have been calculated. In urban and rural areas the main sink of 6-methyl-5-hepten-2-one is reaction with O3 molecules with a residence time in the order of few minutes.

  12. 40 CFR 721.10500 - Acrylated mixed metal oxides (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylated mixed metal oxides (generic... Specific Chemical Substances § 721.10500 Acrylated mixed metal oxides (generic). (a) Chemical substance and... mixed metal oxides (PMN P-06-341) is subject to reporting under this section for the significant...

  13. 40 CFR 721.10500 - Acrylated mixed metal oxides (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylated mixed metal oxides (generic... Specific Chemical Substances § 721.10500 Acrylated mixed metal oxides (generic). (a) Chemical substance and... mixed metal oxides (PMN P-06-341) is subject to reporting under this section for the significant...

  14. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  15. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  16. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  17. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  18. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  19. 40 CFR 721.484 - Fluorinated acrylic copolymer (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Fluorinated acrylic copolymer (generic name). 721.484 Section 721.484 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.484 Fluorinated acrylic copolymer (generic name). (a) Chemical...

  20. 40 CFR 721.336 - Perfluoroalkylethyl acrylate copolymer (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Perfluoroalkylethyl acrylate copolymer (generic name). 721.336 Section 721.336 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.336 Perfluoroalkylethyl acrylate copolymer (generic name). (a)...

  1. The Acrylation of Glycerol: a Precursor to Functionalized Lipids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Didecanoylacryloylglycerol was synthesized from decanoic and acrylic acids and glycerol using K2O as catalyst. This reaction was carried out in hexane in a closed stainless steel reactor at 200°C for 5h. The reactants were added in a 1:3:4 glycerol:decanoic acid:acrylic acid molar ratio. The resu...

  2. 40 CFR 721.330 - Aromatic acrylate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.330 Aromatic acrylate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an aromatic acrylate (PMN P-01-420)...

  3. 40 CFR 721.330 - Aromatic acrylate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.330 Aromatic acrylate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an aromatic acrylate (PMN P-01-420)...

  4. FTIR gas-phase kinetic study on the reactions of OH radicals and Cl atoms with unsaturated esters: Methyl-3,3-dimethyl acrylate, (E)-ethyl tiglate and methyl-3-butenoate

    NASA Astrophysics Data System (ADS)

    Colomer, Juan P.; Blanco, María B.; Peñéñory, Alicia B.; Barnes, Ian; Wiesen, Peter; Teruel, Mariano A.

    2013-11-01

    The relative-rate technique has been used to obtain rates coefficients for the reactions of the unsaturated esters methyl-3,3-dimethyl acrylate, (E)-ethyl tiglate and methyl-3-butenoate with OH radicals and chlorine atoms at (298 ± 2) K in synthetic air at a total pressure of (760 ± 10) Torr. The experiments were performed in an environmental chamber using in situ FTIR detection to monitor the decay of the esters relative to different reference compounds. The following room temperature rate coefficients (in units of cm3 molecule-1 s-1) were obtained: k1(OH + (CH3)2Cdbnd CHC(O)OCH3) = (4.46 ± 1.05) × 10-11, k2(Cl + (CH3)2Cdbnd CHC(O)OCH3) = (2.78 ± 0.46) × 10-10, k3(OH + CH3CHdbnd C(CH3)C(O)OCH2CH3) = (8.32 ± 1.93) × 10-11, k4(Cl + CH3CHdbnd C(CH3)C(O)OCH2CH3) = (2.53 ± 0.35) × 10-10, k5(OH + CH2dbnd CHCH2C(O)OCH3) = (3.16 ± 0.57) × 10-11, k4(Cl + CH2dbnd CHCH2C(O)OCH3) = (2.10 ± 0.35) × 10-10. With the exception of the reaction of Cl with methyl-3,3-dimethyl acrylate (k2), for which one determination exists in the literature, this study is the first kinetic study for these reactions under atmospheric pressure. Reactivity trends are discussed in terms of the effect of the alkyl and ester groups attached to the double bond on the overall rate coefficients towards OH radicals. The atmospheric implications of the reactions were assessed by the estimation of the tropospheric lifetimes of the title reactions.

  5. Electrochemical characterization of aminated acrylic conducting polymer

    NASA Astrophysics Data System (ADS)

    Rashid, Norma Mohammad; Heng, Lee Yook; Ling, Tan Ling

    2015-09-01

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.

  6. Electrochemical characterization of aminated acrylic conducting polymer

    SciTech Connect

    Rashid, Norma Mohammad; Heng, Lee Yook; Ling, Tan Ling

    2015-09-25

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.

  7. Poly(amide-graft-acrylate) interfacial compounds

    NASA Astrophysics Data System (ADS)

    Zamora, Michael Perez

    Graft copolymers with segments of dissimilar chemistries have been shown to be useful in a variety of applications as surfactants, compatibilizers, impact modifiers, and surface modifiers. The most common route to well defined graft copolymers is through the use of macromonomers, polymers containing a reactive functionality and thus capable of further polymerization. However, the majority of the studies thus far have focused on the synthesis of macromonomers capable of reacting with vinyl monomers to form graft copolymers. This study focused on the synthesis of macromonomers capable of participating in condensation polymerizations. A chain transfer functionalization method was utilized. Cysteine was evaluated as a chain transfer agent for the synthesis of amino acid functionalized poly(acrylate) and poly(methacrylate) macromonomers. Low molar mass, functionalized macromonomers were produced. These macromonomers were proven to be capable of reacting with amide precursors to form poly(amide-g-acrylate) graft copolymers. Macromonomers and graft copolymers were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, elemental analysis (EA), inductively coupled plasma (ICP), and differential scanning calorimetry (DSC). The second part of this research involved poly(dimethacrylate) dental restorative materials. Volumetric shrinkage during the cure of these resins results in a poor interface between the resin and the remaining tooth structure, limiting the lifetime of these materials. Cyclic anhydrides were incorporated into common monomer compositions used in dental applications. Volume expansion from the ring opening hydrolysis of these anhydrides was shown to be feasible. The modified dental resins were characterized by swelling, extraction and ultraviolet spectroscopy (UV), and density measurements. Linear poLymers designed to model the crosslinked dental resins were

  8. Methods for the synthesis of deuterated acrylate salts

    SciTech Connect

    Yang, Jun; Bonnesen, Peter V.; Hong, Kunlun

    2014-09-09

    A method for synthesizing a deuterated acrylate of the Formula (1), the method comprising: (i) deuterating a propiolate compound of Formula (2) to a methyne-deuterated propiolate compound of Formula (3) in the presence of a base and D.sub.2O: and (ii) reductively deuterating the methyne-deuterated propiolate compound of Formula (3) in a reaction solvent in the presence of deuterium gas and a palladium-containing catalyst to afford the deuterated acrylate of the Formula (1). The resulting deuterated acrylate compounds, derivatives thereof, and polymers derived therefrom are also described.

  9. Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

    SciTech Connect

    Binder, Thomas; Erpelding, Michael; Schmid, Josef; Chin, Andrew; Sammons, Rhea; Rockafellow, Erin

    2015-04-10

    Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

  10. Investigation of Acrylic Acid at High Pressure Using Neutron Diffraction

    PubMed Central

    2014-01-01

    This article details the exploration of perdeuterated acrylic acid at high pressure using neutron diffraction. The structural changes that occur in acrylic acid-d4 are followed via diffraction and rationalized using the Pixel method. Acrylic acid undergoes a reconstructive phase transition to a new phase at ∼0.8 GPa and remains molecular to 7.2 GPa before polymerizing on decompression to ambient pressure. The resulting product is analyzed via Raman and FT-IR spectroscopy and differential scanning calorimetry and found to possess a different molecular structure compared with polymers produced via traditional routes. PMID:24650085

  11. A simple solubility tests for the discrimination of acrylic and modacrylic fibers.

    PubMed

    Suga, Keisuke; Narita, Yuji; Suzuki, Shinichi

    2014-05-01

    In a crime scene investigation, single fibers play an important role as significant trace physical evidence. Acrylic fibers are frequently encountered in forensic analysis. Currently, acrylic and modacrylic are not discriminated clearly in Japan. Only results of FT-IR, some of acrylics were difficult to separate clearly to acrylic and modacrylic fibers. Solubility test is primitive but convenient useful method, and Japan Industrial Standards (JIS) recommends FT-IR and solubility test to distinguish acrylic and modacrylic fibers. But recommended JIS dissolving test using 100% N,N-dimethylformamide (DMF) as a solvent, some acrylics could not be discriminated. In this report, we used DMF and ethanol (90:10, v/v) solvent. The JIS method could not discriminate 6 acrylics in 60 acrylics; hence, DMF and ethanol (90:10, v/v) solvent discriminated 59 of the 60 fibers (43 acrylic and 16 modacrylic fibers) clearly, but only one modacrylic fiber incorrectly identified as acrylic. PMID:24673494

  12. PMMA-based composite materials with reactive ceramic fillers: IV. Radiopacifying particles embedded in PMMA beads for acrylic bone cements.

    PubMed

    Abboud, M; Casaubieilh, L; Morvan, F; Fontanille, M; Duguet, E

    2000-01-01

    New acrylic bone cements were prepared from alumina particles previously treated by 3-(trimethoxysilyl)propylmethacrylate (gamma-MPS) and embedded in poly(methylmethacrylate-co-ethylacrylate) beads with about 7 mol% of ethyl acrylate repeating units. The encapsulation was performed through a conventional suspension polymerization process. The influence of (i) the concentration of the dispersion stabilizer and (ii) the alumina content upon the shape, size, and size distribution of the acrylic beads was studied. Cements were prepared from each batch by hand-mixing alumina-filled acrylic beads with a liquid monomer mixture containing methyl methacrylate, n-butyl methacrylate, and N,N-dimethyl-p-toluidine. Benzoyl peroxide was previously added to the solid part. The powder-to-liquid ratio was equal to 2 for each formulation. Compressive strength of cured cement decreases with alumina content, whereas compressive modulus remains roughly constant. These results are in contradiction to those obtained for cements based on a mixture of gamma-MPS-treated alumina and unfilled acrylic beads. Nevertheless, they are interpreted in terms of alumina arrangement in the cement. In the first case, alumina particles contribute to the reinforcement of the dispersed acrylic phase, with poor benefits for the whole materials. In the second case, they allow the reinforcement of the continuous acrylic phase and, therefore, the cement's one. PMID:11074433

  13. 21 CFR 177.1060 - n-Alkylglutarimide/acrylic copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... vinyl chloride homo- or copolymers. (e) Conditions of use. The n-alkylglutarimide/acrylic copolymers are used as articles or components of articles (other than articles composed of vinyl chloride homo-...

  14. 21 CFR 177.1060 - n-Alkylglutarimide/acrylic copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... vinyl chloride homo- or copolymers. (e) Conditions of use. The n-alkylglutarimide/acrylic copolymers are used as articles or components of articles (other than articles composed of vinyl chloride homo-...

  15. 21 CFR 177.1060 - n-Alkylglutarimide/acrylic copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .../acrylic copolymers shall not be used as polymer modifiers in vinyl chloride homo- or copolymers. (e... (other than articles composed of vinyl chloride homo- or copolymers) intended for use in contact with...

  16. 21 CFR 177.1060 - n-Alkylglutarimide/acrylic copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... vinyl chloride homo- or copolymers. (e) Conditions of use. The n-alkylglutarimide/acrylic copolymers are used as articles or components of articles (other than articles composed of vinyl chloride homo-...

  17. 21 CFR 177.1060 - n-Alkylglutarimide/acrylic copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... vinyl chloride homo- or copolymers. (e) Conditions of use. The n-alkylglutarimide/acrylic copolymers are used as articles or components of articles (other than articles composed of vinyl chloride homo-...

  18. Use of acrylic sheet molds for elastomeric products

    NASA Technical Reports Server (NTRS)

    Heisman, R. M.; Koerner, A. E.; Messineo, S. M.

    1970-01-01

    Molds constructed of acrylic sheet are more easily machined than metal, are transparent to ensure complete filling during injection, and have smooth surfaces free of contamination. Technique eliminates flashing on molded parts and mold release agents.

  19. Emulsion Polymerization of Butyl Acrylate: Spin Trapping and EPR Study

    NASA Technical Reports Server (NTRS)

    Kim, S.; Westmoreland, D.

    1994-01-01

    The propagating radical in the emulsion polymerization reaction of butyl acrylate was detected by Electron Paramagnetic Resonance spectroscopy using two spin trapping agents, 2-methyl-2nitrosopropane and alpha -N-tert-butylnitrone.

  20. [Treatment of acrylate wastewater by electrocatalytic reduction process].

    PubMed

    Yu, Li-Na; Song, Yu-Dong; Zhou, Yue-Xi; Zhu, Shu-Quan; Zheng, Sheng-Zhi; Ll, Si-Min

    2011-10-01

    High-concentration acrylate wastewater was treated by an electrocatalytic reduction process. The effects of the cation exchange membrane (CEM) and cathode materials on acrylate reduction were investigated. It indicated that the acrylate could be reduced to propionate acid efficiently by the electrocatalytic reduction process. The addition of CEM to separator with the cathode and anode could significantly improve current efficiency. The cathode materials had significant effect on the reduction of acrylate. The current efficiency by Pd/Nickel foam, was greater than 90%, while those by nickel foam, the carbon fibers and the stainless steel decreased successively. Toxicity of the wastewater decreased considerably and methane production rate in the biochemical methane potential (BMP) test increased greatly after the electrocatalytic reduction process. PMID:22279908

  1. PERMEATION OF MULTIFUNCTIONAL ACRYLATES THROUGH SELECTED PROTECTIVE GLOVE MATERIALS

    EPA Science Inventory

    In support of the Premanufacture Notification (PMN) program of the Environmental Protection Agency's Office of Toxic Substances, the resistance of three glove materials to permeation by multifunctional acrylate compounds was evaluated through a program for the Office of Research ...

  2. Stabilizing effects of estertins mercaptide (methyl acrylate) for PVC degradation

    NASA Astrophysics Data System (ADS)

    Zhang, S. H.; Liu, T. M.; Li, J. L.; Wang, C. R.; Li, C.; Wang, Z. Q.

    2016-07-01

    The thermal and UV light (ultraviolet light) stability of PVC films with estertins mercaptide (methyl acrylate), methyltins mercaptide and the compound consisted of estertins mercaptide (methyl acrylate) and hydrotalcite (2:2.5) were investigated by ageing in a circulation oven at 190 °C and irradiating with 72W UV light for 96h, respectively, and then the yellowness and transmission rate were tested by Color Quest XE. Hydrotalcite was proved to have good synergies with estertins mercaptide (methyl acrylate) on improving the thermal stability and UV light stability. The retarding effects of the heat stabilizers to PVC degradation were tested by TGA from 50°C to 600°C. The results show that temperature of HCl evolution from PVC film was improved obviously by compounding with estertins mercaptide(methyl acrylate) and hydrotalcite and estertins mercaptide(methyl acrylate) was found to have a better long term stability. Sn4+ consistence of water and seawater in which films before and after UV light irradiation were soaked for 60 days was analyzed by ICP; the results indicate that the Sn4+ consistence from the films with estertins mercaptide(methyl acrylate) as thermal stabilizer was lower than that from the film with methyltins mercaptide. The crosslink moderately by UV irradiation for PVC films can hold back the dissolution of organotin heat stabilizers from PVC products into water and seawater.

  3. Advances in acrylic-alkyd hybrid synthesis and characterization

    NASA Astrophysics Data System (ADS)

    Dziczkowski, Jamie

    2008-10-01

    In situ graft acrylic-alkyd hybrid resins were formed by polymerizing acrylic and acrylic-mixed monomers in the presence of alkyds by introduction of a free radical initiator to promote graft formation. Two-dimensional NMR, specifically gradient heteronuclear multiple quantum coherence (gHMQC), was used to clarify specific graft sites of the hybrid materials. Both individual and mixed-monomer systems were produced to determine any individual monomer preferences and to model current acrylic-alkyd systems. Different classes of initiators were used to determine any initiator effects on graft location. The 2D-NMR results confirm grafting at doubly allylic hydrogens located on the fatty acid chains and the polyol segment of the alkyd backbone. The gHMQC spectra show no evidence of grafting across double bonds on either pendant fatty acid groups or THPA unsaturation sites for any of the monomer or mixed monomer systems. It was also determined that choice of initiator has no effect on graft location. In addition, a design of experiments using response surface methodology was utilized to obtain a better understanding of this commercially available class of materials and relate both the chemical and physical properties to one another. A Box-Behnkin design was used, varying the oil length of the alkyd phase, the degree of unsaturation in the polyester backbone, and acrylic to alkyd ratio. Acrylic-alkyd hybrid resins were reduced with an amine/water mixture. Hydrolytic stability was tested and viscoelastic properties were obtained to determine crosslink density. Cured films were prepared and basic coatings properties were evaluated. It was found that the oil length of the alkyd is the most dominant factor for final coatings properties of the resins. Acrylic to alkyd ratio mainly influences the resin properties such as acid number, average molecular weight, and hydrolytic stability. The degree of unsaturation in the alkyd backbone has minimal effects on resin and film

  4. Industrially relevant epoxy-acrylate hybrid resin photopolymerizations

    NASA Astrophysics Data System (ADS)

    Ajiboye, Gbenga I.

    Photopolymerization of epoxy-acrylate hybrid resins takes advantages of inherent properties present in the free-radical and cationic reactions to reduce oxygen inhibition problems that plague free-radical reactions. Similarly, the combined reaction mechanisms reduce moisture sensitivity of the cationic reactions. Despite the advantages of epoxy-acrylate hybrid resins, problems persist that need to be addressed. For example, low conversion and polymerization rate of the epoxides are a problem, because the fast acrylate conversion prevents the epoxide from reaching high conversion. Controlling phase separation is challenging, since two moieties with different properties are reacting. The physical properties of the polymer will be impacted by the availability of different moieties. High shrinkage stress results from the acrylate moiety, causing buckling and cracking in film and coating applications. The overall goal of this study is to use the fundamental knowledge of epoxy-acrylate hybrid resins to formulate industrially viable polymers. In order to achieve this goal, the study focuses on the following objectives: (I) determine the apparent activation energy of the hybrid monomer METHB, (II) increase epoxide conversion and polymerization rate of hybrid formulations, and (III) control physical properties in epoxy-acrylate hybrid resins. In order to increase the epoxide conversion and rate of polymerization, the sensitivity of epoxides to alcohol is used to facilitate the activated monomer (AM) mechanism and induce a covalent bond between the epoxide and acrylate polymers through the hydroxyl group. It is hypothesized that if the AM mechanism is facilitated, epoxide conversion will increase. As a result, the resins can be tailored to control phase separation and physical properties, and shrinkage stress can be reduced. In pursuit of these objectives, the hybrid monomer METHB was polymerized at temperatures ranging from 30°C to 70°C to obtain apparent activation

  5. The sensitizing capacity of multifunctional acrylates in the guinea pig.

    PubMed

    Björkner, B

    1984-10-01

    The multifunctional acrylates used in ultraviolet (UV) curable resins act as cross-linkers and "diluents". They are usually based on di(meth)acrylate esters of dialcohols or tri- and tetra-acrylate esters of polyalcohols. In UV-curable coatings, the most commonly used are pentaerythritol triacrylate (PETA), trimethylolpropane triacrylate (TMPTA) and 1,6-hexanediol diacrylate (HDDA). In other uses, such as dental composite resin materials, the dimethacrylic monomers based on n-ethylene glycol are the most useful. The sensitizing capacity of various multifunctional acrylates and their cross-reactivity pattern have been investigated with the guinea pig maximization test. The tests show that BUDA (1,4-butanediol diacrylate) and HDDA are moderate to strong sensitizers and that they probably cross-react with each other. The n-ethylene glycol diacrylates and methacrylates tested are weak or non-sensitizers. Tripropylene glycol diacrylate (TPGDA) is a moderate and neopentyl glycol diacrylate (NPGDA) a strong sensitizer, whereas neopentyl glycol dimethacrylate is a non-sensitizer. The commercial PETA is a mixture of pentaerythritol tri- and tetra-acrylate (PETA-3 and PETA-4). PETA-3 is a much stronger sensitizer than PETA-4. Simultaneous reactions were seen between PETA-3, PETA-4 and TMPTA. The oligotriacrylate OTA 480 is a moderate sensitizer, but no concomitant reactions were seen with PETA-3, PETA-4 or TMPTA. Of the multifunctional acrylates tested, the di- and triacrylic compounds should be regarded as potent sensitizers. The methacrylated multifunctional acrylic compounds are weak or non-sensitizers. PMID:6499426

  6. Impact Delamination and Fracture in Aluminum/Acrylic Sandwich Plates

    NASA Technical Reports Server (NTRS)

    Liaw, Benjamin; Zeichner, Glenn; Liu, Yanxiong; Bowles, Kenneth J. (Technical Monitor)

    2000-01-01

    Impact-induced delamination and fracture in 6061-T6 aluminum/cast acrylic sandwich plates adhered by epoxy were generated in an instrumented drop-weight impact machine. Although only a small dent was produced on the aluminum side when a hemispherical penetrator tup was dropped onto it from a couple of inches, a large ring of delamination at the interface was observed. The delamination damage was often accompanied by severe shattering in the acrylic substratum. Damage patterns in the acrylic layer include radial and ring cracks and, together with delamination at the interface, may cause peeling-off of acrylic material from the sandwich plate. Theory of stress-wave propagation can be used to explain these damage patterns. The impact tests were conducted at various temperatures. The results also show clearly that temperature effect is very important in impact damage. For pure cast acrylic nil-ductile transition (NDT) occurs between 185-195 F. Excessive impact energy was dissipated into fracture energy when tested at temperature below this range or through plastic deformation when tested at temperature above the NDT temperature. Results from this study will be used as baseline data for studying fiber-metal laminates, such as GLARE and ARALL for advanced aeronautical and astronautical applications.

  7. Properties of the modified cellulosic fabrics using polyurethane acrylate copolymers.

    PubMed

    Tabasum, Shazia; Zuber, Mohammad; Jabbar, Abdul; Zia, Khalid Mahmood

    2013-05-15

    Polyurethane acrylate copolymers (PAC) were synthesized via emulsion polymerization following three step synthesis process using toluene-2,4-diisocyanate, hydroxy terminated poly(caprolactone) diol, 2-hydroxyethylacrylate (HEA) and butyl acrylate (BuA). Structural characteristics of the synthesized polyurethane acrylate copolymer (PAC) were studied using Fourier Transform Infrared (FT-IR) spectrophotometer and are with accordance with the proposed PAC structure. The physicochemical properties such as solid contents (%), tackiness, film appearance and emulsion stability were studied, discussed and co-related with other findings. The plain weave poly-cotton printed fabrics after application of PAC was evaluated applying colorfastness standard test method. The results revealed that emulsion stability is the main controlling factor of the synthesized material in order to get better applications and properties. The emulsion stability of the synthesized material increased with increase in molecular weight of the polycaprolactone diol. PMID:23544644

  8. Biocatalytic functionalization of hydroxyalkyl acrylates and phenoxyethanol via phosphorylation.

    PubMed

    Tasnádi, Gábor; Hall, Mélanie; Baldenius, Kai; Ditrich, Klaus; Faber, Kurt

    2016-09-10

    The enzymatic phosphorylation of phenoxyethanol, 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate catalyzed by acid phosphatases PhoN-Sf and PiACP at the expense of inorganic di-, tri-, hexameta- or polyphosphate was applied to the preparative-scale synthesis of phosphorylated compounds. The reaction conditions were optimized with respect to enzyme immobilization, substrate concentration, pH and type of phosphate donor. The mild reaction conditions prevented undesired polymerization and hydrolysis of the acrylate ester moiety. Application of a continuous flow system allowed facile scale-up and mono-phosphates were obtained in up to 26% isolated yield with space-time yields of 0.89kgL(-1)h(-1). PMID:27422352

  9. Biosynthetic pathway for acrylic acid from glycerol in recombinant Escherichia coli.

    PubMed

    Tong, Wenhua; Xu, Ying; Xian, Mo; Niu, Wei; Guo, Jiantao; Liu, Huizhou; Zhao, Guang

    2016-06-01

    Acrylic acid is an important industrial feedstock. In this study, a de novo acrylate biosynthetic pathway from inexpensive carbon source glycerol was constructed in Escherichia coli. The acrylic acid was produced from glycerol via 3-hydroxypropionaldehyde, 3-hydroxypropionyl-CoA, and acrylyl-CoA. The acrylate production was improved by screening and site-directed mutagenesis of key enzyme enoyl-CoA hydratase and chromosomal integration of some exogenous genes. Finally, our recombinant strain produced 37.7 mg/L acrylic acid under shaking flask conditions. Although the acrylate production is low, our study shows feasibility of engineering an acrylate biosynthetic pathway from inexpensive carbon source. Furthermore, the reasons for limited acrylate production and further strain optimization that should be performed in the future were also discussed. PMID:26782744

  10. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... substituted methyl styrene, methyl methacrylate, and substituted silane. 721.6920 Section 721.6920 Protection... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  11. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... substituted methyl styrene, methyl methacrylate, and substituted silane. 721.6920 Section 721.6920 Protection... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  12. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... substituted methyl styrene, methyl methacrylate, and substituted silane. 721.6920 Section 721.6920 Protection... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  13. Technology and the use of acrylics for provisional dentine protection.

    PubMed

    Kapusevska, Biljana; Dereban, Nikola; Popovska, Mirjana; Nikolovska, Julijana; Radojkova Nikolovska, Vеrа; Zabokova Bilbilova, Efka; Mijoska, Aneta

    2013-01-01

    Acrylics are compounds polymerized from monomers of acrylic, metacrylic acid or acrylonitrates. The purpose of this paper is to present the technology and use of acrylics for provisional dentine protection in the practice of dental prosthodontics. For this reason, we followed 120 clinical cases from the everyday clinical practice, divided into 4 groups of 30 patients who needed prosthetic reconstruction. The first group included cases in which we applied celluloid crowns for dentine protection, for the second group we used acrylic teeth from a set of teeth for complete dentures; in the third and fourth groups the fabrication was done with the system of an impression matrix and the acrylic resin block technique respectively. In all the examined patients, the gingival index by Silness and Loe and the vitality of the dental pulp were verified clinically, after preparation and 8 days from the placement of the provisional crown. The value for dental sensitivity measured after preparation was 2.59, and 8 days after the placement of the provisional crown it bwas 3.1. From these results we can conclude that after the 8th day from the placement of the provisional crown, there was an adaptation period, characterized by a decrease in the painful sensations. The value of the Silness and Loe gingival index measured after the preparation was 1.34, and 8 days from the placement of the provisional crown was 0.94. The results inclined us to the fact that the provisional acrylic crowns facilitated the reparation of the periodontal tissue. PMID:24566021

  14. Colour Stability of Heat and Cold Cure Acrylic Resins

    PubMed Central

    Ganesh, P R; Reddy, Madan Mohan; Ebenezar, A.V. Rajesh; Sivakumar, G

    2015-01-01

    Introduction: To evaluate the colour stability of heat and cold cure acrylic resins under simulated oral conditions with different colorants. Materials and Methods: Three different brands of heat cure acrylic resin and two rapid cure auto polymerizing acrylic resin of commercial products such as Trevelon Heat Cure (THC), DPI Heat cure (DHC), Pyrax Heat Cure (PHC), DPI Cold cure (DCC) and Acralyn-R-Cold cure (ACC) have been evaluated for discoloration and colour variation on subjecting it to three different, commonly employed food colorants such as Erythrosine, Tartarizine and Sunset yellow. In order to simulate the oral condition the food colorants were diluted with artificial saliva to the samples taken up for the study. These were further kept in an incubator at 37°C ± 1°C. The UV-visible spectrophotometer has been utilized to evaluate the study on the basis of CIE L* a* b* system. The prepared samples for standard evaluation have been grouped as control group, which has been tested with a white as standard, which is applicable for testing the colour variants. Results: The least colour changes was found to be with Sunset Yellow showing AE* value of 3.55 with heat cure acrylic resin branded as PHC material and the highest colour absorption with Tartarizine showing AE* value of 12.43 in rapid cure autopolymerzing acrylic resin material branded as ACC material. Conclusion: ACC which is a self cure acrylic resin shows a higher colour variation to the tartarizine food coloration. There were not much of discoloration values shown on the denture base resins as the food colorants are of organic azodyes. PMID:25738078

  15. Effects of denture teeth on the dimensional accuracy of acrylic resin denture bases.

    PubMed

    Baemmert, R J; Lang, B R; Barco, M T; Billy, E J

    1990-01-01

    The Michigan Computer-Graphics Coordinate Measurement System was used to determine the effects of artificial denture teeth on the accuracy of acrylic resin denture bases. Two poly(methyl methacrylate) acrylic resins and two processing techniques were tested. Groups processed with denture teeth reproduced more accurate points than groups processed without denture teeth. Groups processed with a conventional heat-polymerized acrylic resin reproduced more accurate points than groups polymerized with an injection pressing type of acrylic resin. PMID:2083021

  16. Dispersion Morphology of Poly(methyl acrylate)/Silica Nanocomposites

    SciTech Connect

    D Janes; J Moll; S Harton; C Durning

    2011-12-31

    Nearly monodisperse poly(methyl acrylate) (PMA) and spherical SiO{sub 2} nanoparticles (NP, d = 14 {+-} 4 nm) were co-cast from 2-butanone, a mutually good solvent and a displacer of adsorbed PMA from silica. The effects of NP content and post-casting sample history on the dispersion morphology were found by small-angle X-ray scattering supplemented by transmission electron microscopy. Analysis of the X-ray results show that cast and thermally annealed samples exhibited a nearly random particle dispersion. That the same samples, prior to annealing, were not well-dispersed is indicative of thermodynamic miscibility during thermal annealing over the range of NP loadings studied. A simple mean-field thermodynamic model suggests that miscibility results primarily from favorable polymer segment/NP surface interactions. The model also indicates, and experiments confirm, that subsequent exposure of the composites to the likely displacer ethyl acetate results in entropic destabilization and demixing into NP-rich and NP-lean phases.

  17. Regulation of the Contribution of Integrin to Cell Attachment on Poly(2-Methoxyethyl Acrylate) (PMEA) Analogous Polymers for Attachment-Based Cell Enrichment.

    PubMed

    Hoshiba, Takashi; Nemoto, Eri; Sato, Kazuhiro; Orui, Toshihiko; Otaki, Takayuki; Yoshihiro, Ayano; Tanaka, Masaru

    2015-01-01

    Cell enrichment is currently in high demand in medical engineering. We have reported that non-blood cells can attach to a blood-compatible poly(2-methoxyethyl acrylate) (PMEA) substrate through integrin-dependent and integrin-independent mechanisms because the PMEA substrate suppresses protein adsorption. Therefore, we assumed that PMEA analogous polymers can change the contribution of integrin to cell attachment through the regulation of protein adsorption. In the present study, we investigated protein adsorption, cell attachment profiles, and attachment mechanisms on PMEA analogous polymer substrates. Additionally, we demonstrated the possibility of attachment-based cell enrichment on PMEA analogous polymer substrates. HT-1080 and MDA-MB-231 cells started to attach to poly(butyl acrylate) (PBA) and poly(tetrahydrofurfuryl acrylate) (PTHFA), on which proteins could adsorb well, within 1 h. HepG2 cells started to attach after 1 h. HT-1080, MDA-MB-231, and HepG2 cells started to attach within 30 min to PMEA, poly(2-(2-methoxyethoxy) ethyl acrylate-co-butyl acrylate) (30:70 mol%, PMe2A) and poly(2-(2-methoxyethoxy) ethoxy ethyl acrylate-co-butyl acrylate) (30:70 mol%, PMe3A), which suppress protein adsorption. Moreover, the ratio of attached cells from a cell mixture can be changed on PMEA analogous polymers. These findings suggested that PMEA analogous polymers can be used for attachment-based cell enrichment. PMID:26288362

  18. Regulation of the Contribution of Integrin to Cell Attachment on Poly(2-Methoxyethyl Acrylate) (PMEA) Analogous Polymers for Attachment-Based Cell Enrichment

    PubMed Central

    Hoshiba, Takashi; Nemoto, Eri; Sato, Kazuhiro; Orui, Toshihiko; Otaki, Takayuki; Yoshihiro, Ayano; Tanaka, Masaru

    2015-01-01

    Cell enrichment is currently in high demand in medical engineering. We have reported that non-blood cells can attach to a blood-compatible poly(2-methoxyethyl acrylate) (PMEA) substrate through integrin-dependent and integrin-independent mechanisms because the PMEA substrate suppresses protein adsorption. Therefore, we assumed that PMEA analogous polymers can change the contribution of integrin to cell attachment through the regulation of protein adsorption. In the present study, we investigated protein adsorption, cell attachment profiles, and attachment mechanisms on PMEA analogous polymer substrates. Additionally, we demonstrated the possibility of attachment-based cell enrichment on PMEA analogous polymer substrates. HT-1080 and MDA-MB-231 cells started to attach to poly(butyl acrylate) (PBA) and poly(tetrahydrofurfuryl acrylate) (PTHFA), on which proteins could adsorb well, within 1 h. HepG2 cells started to attach after 1 h. HT-1080, MDA-MB-231, and HepG2 cells started to attach within 30 min to PMEA, poly(2-(2-methoxyethoxy) ethyl acrylate-co-butyl acrylate) (30:70 mol%, PMe2A) and poly(2-(2-methoxyethoxy) ethoxy ethyl acrylate-co-butyl acrylate) (30:70 mol%, PMe3A), which suppress protein adsorption. Moreover, the ratio of attached cells from a cell mixture can be changed on PMEA analogous polymers. These findings suggested that PMEA analogous polymers can be used for attachment-based cell enrichment. PMID:26288362

  19. ACUTE TOXICITY AND BEHAVIORAL EFFECTS OF ACRYLATES AND METHACRYLATES TO JUVENILE FATHEAD MINNOWS (JOURNAL VERSION)

    EPA Science Inventory

    Acrylate and methacrylate esters are reactive monomers that are used primarily in the synthesis of acrylic plastics and polymers. Ninety-six hour flow-through acute toxicity tests were conducted with fathead minnows (Pimephales promelas) using 6 acrylates and 6 methacrylates. Nin...

  20. 40 CFR 721.9640 - Salt of an acrylic acid - acrylamide terpolymer (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Salt of an acrylic acid - acrylamide... Specific Chemical Substances § 721.9640 Salt of an acrylic acid - acrylamide terpolymer (generic). (a... generically as salt of an acrylic acid - acrylamide terpolymer (PMN P-99-817) is subject to reporting...

  1. 40 CFR 721.9640 - Salt of an acrylic acid - acrylamide terpolymer (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Salt of an acrylic acid - acrylamide... Specific Chemical Substances § 721.9640 Salt of an acrylic acid - acrylamide terpolymer (generic). (a... generically as salt of an acrylic acid - acrylamide terpolymer (PMN P-99-817) is subject to reporting...

  2. 40 CFR 721.321 - Substituted acrylamides and acrylic acid copolymer (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted acrylamides and acrylic... New Uses for Specific Chemical Substances § 721.321 Substituted acrylamides and acrylic acid copolymer... identified generically as substituted acrylamides and acrylic acid copolymer (PMN P-00-0490) is subject...

  3. 40 CFR 721.321 - Substituted acrylamides and acrylic acid copolymer (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted acrylamides and acrylic... New Uses for Specific Chemical Substances § 721.321 Substituted acrylamides and acrylic acid copolymer... identified generically as substituted acrylamides and acrylic acid copolymer (PMN P-00-0490) is subject...

  4. 40 CFR 721.9640 - Salt of an acrylic acid - acrylamide terpolymer (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Salt of an acrylic acid - acrylamide... Specific Chemical Substances § 721.9640 Salt of an acrylic acid - acrylamide terpolymer (generic). (a... generically as salt of an acrylic acid - acrylamide terpolymer (PMN P-99-817) is subject to reporting...

  5. 40 CFR 721.9640 - Salt of an acrylic acid - acrylamide terpolymer (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Salt of an acrylic acid - acrylamide... Specific Chemical Substances § 721.9640 Salt of an acrylic acid - acrylamide terpolymer (generic). (a... generically as salt of an acrylic acid - acrylamide terpolymer (PMN P-99-817) is subject to reporting...

  6. 40 CFR 721.9640 - Salt of an acrylic acid - acrylamide terpolymer (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Salt of an acrylic acid - acrylamide... Specific Chemical Substances § 721.9640 Salt of an acrylic acid - acrylamide terpolymer (generic). (a... generically as salt of an acrylic acid - acrylamide terpolymer (PMN P-99-817) is subject to reporting...

  7. 40 CFR 721.321 - Substituted acrylamides and acrylic acid copolymer (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted acrylamides and acrylic... New Uses for Specific Chemical Substances § 721.321 Substituted acrylamides and acrylic acid copolymer... identified generically as substituted acrylamides and acrylic acid copolymer (PMN P-00-0490) is subject...

  8. 40 CFR 721.10192 - Amides, coco, N-[3-(dibutylamino)propyl], acrylates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amides, coco, N- , acrylates. 721... Substances § 721.10192 Amides, coco, N- , acrylates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amides, coco, N- , acrylates (PMN...

  9. 40 CFR 721.10192 - Amides, coco, N-[3-(dibutylamino)propyl], acrylates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amides, coco, N- , acrylates. 721... Substances § 721.10192 Amides, coco, N- , acrylates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amides, coco, N- , acrylates (PMN...

  10. 40 CFR 721.10101 - Copolymer of alkyl acrylate and ethyleneglycol dimethacrylate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copolymer of alkyl acrylate and... Significant New Uses for Specific Chemical Substances § 721.10101 Copolymer of alkyl acrylate and...) The chemical substance identified generically as copolymer of alkyl acrylate and...

  11. 21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Vinylidene chloride/methyl acrylate/methyl methacrylate polymers. The vinylidene chloride/methyl acrylate/methyl methacrylate polymers (CAS Reg. No. 34364-83-5) identified in paragraph (a) of this section may be.../methyl acrylate/methyl methacrylate polymers consist of basic polymers produced by the...

  12. 21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Vinylidene chloride/methyl acrylate/methyl methacrylate polymers. The vinylidene chloride/methyl acrylate/methyl methacrylate polymers (CAS Reg. No. 34364-83-5) identified in paragraph (a) of this section may be.../methyl acrylate/methyl methacrylate polymers consist of basic polymers produced by the...

  13. 40 CFR 721.10032 - Acrylic acid, polymer with substituted acrylamides (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.10032 Acrylic acid, polymer with substituted acrylamides (generic). (a... generically as acrylic acid, polymer with substituted acrylamides (PMN P-02-269) is subject to reporting...

  14. 40 CFR 721.463 - Acrylate of polymer based on isophorone diisocyanate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylate of polymer based on... New Uses for Specific Chemical Substances § 721.463 Acrylate of polymer based on isophorone... substance identified generically as acrylate of polymer based on isophorone diisocyanate (PMN P-00-0626)...

  15. 40 CFR 721.6560 - Acrylic acid, polymer with substituted ethene.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.6560 Acrylic acid, polymer with substituted ethene. (a) Chemical... as acrylic acid, polymer with substituted ethene (PMN P-91-521) is subject to reporting under...

  16. 40 CFR 721.6560 - Acrylic acid, polymer with substituted ethene.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.6560 Acrylic acid, polymer with substituted ethene. (a) Chemical... as acrylic acid, polymer with substituted ethene (PMN P-91-521) is subject to reporting under...

  17. 40 CFR 721.10032 - Acrylic acid, polymer with substituted acrylamides (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.10032 Acrylic acid, polymer with substituted acrylamides (generic). (a... generically as acrylic acid, polymer with substituted acrylamides (PMN P-02-269) is subject to reporting...

  18. 40 CFR 721.10032 - Acrylic acid, polymer with substituted acrylamides (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.10032 Acrylic acid, polymer with substituted acrylamides (generic). (a... generically as acrylic acid, polymer with substituted acrylamides (PMN P-02-269) is subject to reporting...

  19. 40 CFR 721.463 - Acrylate of polymer based on isophorone diisocyanate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylate of polymer based on... New Uses for Specific Chemical Substances § 721.463 Acrylate of polymer based on isophorone... substance identified generically as acrylate of polymer based on isophorone diisocyanate (PMN P-00-0626)...

  20. 40 CFR 721.463 - Acrylate of polymer based on isophorone diisocyanate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Acrylate of polymer based on... New Uses for Specific Chemical Substances § 721.463 Acrylate of polymer based on isophorone... substance identified generically as acrylate of polymer based on isophorone diisocyanate (PMN P-00-0626)...

  1. 40 CFR 721.6560 - Acrylic acid, polymer with substituted ethene.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.6560 Acrylic acid, polymer with substituted ethene. (a) Chemical... as acrylic acid, polymer with substituted ethene (PMN P-91-521) is subject to reporting under...

  2. 40 CFR 721.6560 - Acrylic acid, polymer with substituted ethene.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.6560 Acrylic acid, polymer with substituted ethene. (a) Chemical... as acrylic acid, polymer with substituted ethene (PMN P-91-521) is subject to reporting under...

  3. 40 CFR 721.10032 - Acrylic acid, polymer with substituted acrylamides (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.10032 Acrylic acid, polymer with substituted acrylamides (generic). (a... generically as acrylic acid, polymer with substituted acrylamides (PMN P-02-269) is subject to reporting...

  4. 40 CFR 721.463 - Acrylate of polymer based on isophorone diisocyanate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylate of polymer based on... New Uses for Specific Chemical Substances § 721.463 Acrylate of polymer based on isophorone... substance identified generically as acrylate of polymer based on isophorone diisocyanate (PMN P-00-0626)...

  5. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  6. 40 CFR 721.338 - Salt of an acrylate copolymer (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Salt of an acrylate copolymer (generic... Substances § 721.338 Salt of an acrylate copolymer (generic). Link to an amendment published at 79 FR 34636... substances identified generically as salt of an acrylate copolymer (PMNs P-00-0333 and P-00-0334) are...

  7. 40 CFR 721.338 - Salt of an acrylate copolymer (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Salt of an acrylate copolymer (generic... Substances § 721.338 Salt of an acrylate copolymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as salt of an acrylate...

  8. 40 CFR 721.338 - Salt of an acrylate copolymer (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Salt of an acrylate copolymer (generic... Substances § 721.338 Salt of an acrylate copolymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as salt of an acrylate...

  9. 40 CFR 721.6560 - Acrylic acid, polymer with substituted ethene.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.6560 Acrylic acid, polymer with substituted ethene. (a) Chemical... as acrylic acid, polymer with substituted ethene (PMN P-91-521) is subject to reporting under...

  10. 40 CFR 721.10223 - Styrenyl surface treated manganese ferrite with acrylic ester polymer (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ferrite with acrylic ester polymer (generic). 721.10223 Section 721.10223 Protection of Environment... manganese ferrite with acrylic ester polymer (generic). (a) Chemical substance and significant new uses... manganese ferrite with acrylic ester polymer (PMN P-09-582) is subject to reporting under this section...

  11. 40 CFR 721.10032 - Acrylic acid, polymer with substituted acrylamides (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acrylic acid, polymer with substituted... Specific Chemical Substances § 721.10032 Acrylic acid, polymer with substituted acrylamides (generic). (a... generically as acrylic acid, polymer with substituted acrylamides (PMN P-02-269) is subject to reporting...

  12. 40 CFR 721.463 - Acrylate of polymer based on isophorone diisocyanate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acrylate of polymer based on... New Uses for Specific Chemical Substances § 721.463 Acrylate of polymer based on isophorone... substance identified generically as acrylate of polymer based on isophorone diisocyanate (PMN P-00-0626)...

  13. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  14. Tensile bond strength between auto-polymerized acrylic resin and acrylic denture teeth treated with MF-MA solution

    PubMed Central

    2016-01-01

    PURPOSE This study evaluated the effect of chemical surface treatment using methyl formate-methyl acetate (MF-MA) solution on the tensile bond strength between acrylic denture teeth and auto-polymerized acrylic resin. MATERIALS AND METHODS Seventy maxillary central incisor acrylic denture teeth for each of three different brands (Yamahachi New Ace; Major Dent; Cosmo HXL) were embedded with incisal edge downwards in auto-polymerized resin in polyethylene pipes and ground with silicone carbide paper on their ridge lap surfaces. The teeth of each brand were divided into seven groups (n=10): no surface treatment (control group), MF-MA solution at a ratio of 25:75 (v/v) for 15 seconds, 30 seconds, 60 seconds, 120 seconds, 180 seconds, and MMA for 180 seconds. Auto-polymerized acrylic resin (Unifast Trad) was applied to the ground surface and polymerized in a pressure cooker. A tensile strength test was performed with a universal testing machine. Statistical analysis of the results was performed using two-way analysis of variance (ANOVA) and post-hoc Dunnett T3 test (α=.05). RESULTS The surface treatment groups had significantly higher mean tensile bond strengths compared with the control group (P<.05) when compared within the same brand. Among the surface treatment groups of each brand, there were no significantly different tensile bond strengths between the MF-MA groups and the MMA 180 second group (P>.05), except for the Yamahachi New Ace MF-MA 180-second group (P<.05). CONCLUSION 15-second MF-MA solution can be an alternative chemical surface treatment for repairing a denture base and rebonding acrylic denture teeth with auto-polymerized acrylic resin, for both conventional and cross-linked teeth. PMID:27555897

  15. Degradation of a Sodium Acrylate Oligomer by an Arthrobacter sp

    PubMed Central

    Hayashi, Takaya; Mukouyama, Masaharu; Sakano, Kouichi; Tani, Yoshiki

    1993-01-01

    Arthrobacter sp. strain NO-18 was first isolated from soil as a bacterium which could degrade the sodium acrylate oligomer and utilize it as the sole source of carbon. When 0.2% (wt/wt) oligomer was added to the culture medium, the acrylate oligomer was found to be degraded by 70 to 80% in 2 weeks, using gel permeation chromatography. To determine the maximum molecular weight for biodegradation, the degradation test was done with the hexamer, heptamer, and octamer, which were separated from the oligomer mixture by fractional gel permeation chromatography. The hexamer and heptamer were consumed to the extents of 58 and 36%, respectively, in 2 weeks, but the octamer was not degraded. Oligomers with three different terminal groups were synthesized to examine the effect of the different terminal groups on biodegradation, but few differences were found. Arthrobacter sp. NO-18 assimilated acrylic acid, propionic acid, glutaric acid, 2-methylglutaric acid, and 1,3,5-pentanetricarboxylic acid. Degradation of the acrylic unit structure by this strain is discussed. PMID:8517751

  16. JKR studies of adhesion with model acrylic elastomers

    SciTech Connect

    Shull, K.R.; Ahn, D.

    1996-12-31

    Acrylic elastomers are widely used in coating applications because of their inherent thermal stability, oil resistance and adhesive properties. These same features make acrylic elastomers attractive for fundamental studies of polymer adhesion. This endeavor has been simplified recently by the development of techniques for producing monodisperse acrylic homopolymers and block copolymers from anionically synthesized parent polyacrylates, thus allowing precise microstructural control of adhering surfaces. In terms of the adhesion measurement itself, an adhesion test based upon the theory of Johnson, Kendall and Roberts (JKR), henceforth referred to as the JKR technique, is well suited for probing the molecular origins of adhesion in elastomeric systems. This technique is quite practical, and minimizes the sample volume to reduce bulk viscoelastic losses. Further, the JKR technique permits testing at very low crack velocities, where interfacial effects are unobscured by bulk effects. In this paper, the authors report the results of JKR adhesion tests between poly(n-butyl acrylate) (PNBA) elastomers and poly(methyl methacrylate) (PMMA). The latter is employed as a control substrate because its inertness and low surface energy (relative to metallic or silicon based surfaces) are conducive to the creation of reproducible solid surfaces.

  17. 40 CFR 721.10519 - Perfluoroalkyl acrylate copolymer (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Perfluoroalkyl acrylate copolymer (generic). 721.10519 Section 721.10519 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances §...

  18. 40 CFR 721.329 - Halogenated benzyl ester acrylate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... halogenated benzyl ester acrylate (PMN P-90-1527) is subject to reporting under this section for the... processors of this substance as specified in § 721.125 (a), (b), (c), (d), (f), (g), (h), and (i). (2... substance may cause internal organ effects (kidney and blood). The requirements of this section do not...

  19. Humidity-responsive starch-poly (methyl acrylate) films.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blown films prepared from starch-poly(methyl acrylate) graft copolymers plasticized with urea and water display shrinkage at relative humidities greater than 50%. Shrinkage at relative humidities below approximately 75% is strongly correlated with the urea/starch weight ratio, which controls the eq...

  20. Acrylic resin injection method for blood vessel investigations.

    PubMed

    Suwa, Fumihiko; Uemura, Mamoru; Takemura, Akimichi; Toda, Isumi; Fang, Yi-Ru; Xu, Yuan Jin; Zhang, Zhi Yuan

    2013-01-01

    The injection of acrylic resin into vessels is an excellent method for macroscopically and microscopically observing their three-dimensional features. Conventional methods can be enhanced by removal of the polymerization inhibitor (hydroquinone) without requiring distillation, a consistent viscosity of polymerized resin, and a constant injection pressure and speed. As microvascular corrosion cast specimens are influenced by viscosity, pressure, and speed changes, injection into different specimens yields varying results. We devised a method to reduce those problems. Sodium hydroxide was used to remove hydroquinone from commercial methylmethacrylate. The solid polymer and the liquid monomer were mixed using a 1 : 9 ratio (low-viscosity acrylic resin, 9.07 ± 0.52 mPa•s) or a 3:7 ratio (high-viscosity resin, 1036.33 ± 144.02 mPa•s). To polymerize the acrylic resin for injection, a polymerization promoter (1.0% benzoyl peroxide) was mixed with a polymerization initiator (0.5%, N, N-dimethylaniline). The acrylic resins were injected using a precise syringe pump, with a 5-mL/min injection speed and 11.17 ± 1.60 mPa injection pressure (low-viscosity resin) and a 1-mL/min injection speed and 58.50 ± 5.75 mPa injection pressure (high-viscosity resin). Using the aforementioned conditions, scanning electron microscopy indicated that sufficient resin could be injected into the capillaries of the microvascular corrosion cast specimens. PMID:24107720

  1. 40 CFR 721.330 - Aromatic acrylate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Aromatic acrylate (generic). 721.330 Section 721.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES... section. (2) The significant new uses are: (i) Release to water. Requirements as specified §...

  2. Synthesis of novel polyfluorinated acrylic monomers and oligomers

    SciTech Connect

    Antonucci, J.M.; Stansbury, J.W.

    1993-12-31

    An unhindered tertiary amine catalyzed reaction of monofunctional and difunctional hydrocarbon acrylates with paraformaldehyde under neat conditions yields unique difunctional acrylic monomers and oligomers, respectively. These multifunctional vinyl products have a predominantly 1,6-diene structure which favors cyclopolymerization. This reaction has been extended to the synthesis of similar polyfluorinated aliphatic monomers arrangements are determined by the nature of their fluoroester groups, e.g.-CF{sub 2}CH{sub 2}O{sub 2}C- favors a 1,4-diene rather than a 1,6-diene structure. In the present study the scope of this novel formaldehyde/acrylate insertion condensation reaction was further extended to include the synthesis of polyfluorinated aryl difunctional monomers and oligomers, e.g. from 2,3,4,5,6-pentafluorobenzyl acrylate and hexafluorobisphenol A diacrylate. The former did not require DMSO and yielded 1,6-, 1,8- and 1,10-dienes whereas the latter required DMSO and yielded oligomers mainly with 1,4-diene linkages.

  3. 40 CFR 721.484 - Fluorinated acrylic copolymer (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.484 Fluorinated acrylic copolymer (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as...

  4. 40 CFR 721.329 - Halogenated benzyl ester acrylate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.329 Halogenated benzyl ester acrylate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically...

  5. 40 CFR 721.329 - Halogenated benzyl ester acrylate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.329 Halogenated benzyl ester acrylate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically...

  6. 40 CFR 721.484 - Fluorinated acrylic copolymer (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.484 Fluorinated acrylic copolymer (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as...

  7. Bond strength between acrylic resin and maxillofacial silicone

    PubMed Central

    HADDAD, Marcela Filié; GOIATO, Marcelo Coelho; dos SANTOS, Daniela Micheline; CREPALDI, Nádia de Marchi; PESQUEIRA, Aldiéris Alves; BANNWART, Lisiane Cristina

    2012-01-01

    The development of implant dentistry improved the possibilities of rehabilitation with maxillofacial prosthesis. However, clinically it is difficult to bond the silicone to the attachment system. Objectives This study aimed to evaluate the effect of an adhesive system on the bond strength between acrylic resin and facial silicone. Material and Methods A total of 120 samples were fabricated with auto-polymerized acrylic resin and MDX 4-4210 facial silicone. Both materials were bonded through mechanical retentions and/or application of primers (DC 1205 primer and Sofreliner primer S) and adhesive (Silastic Medical Adhesive Type A) or not (control group). Samples were divided into 12 groups according to the method used to attach the silicone to the acrylic resin. All samples were subjected to a T-peel test in a universal testing machine. Failures were classified as adhesive, cohesive or mixed. The data were evaluated by the analysis of variance (ANOVA) and the Tukey's HSD test (α=.05). Results The highest bond strength values (5.95 N/mm; 3.07 N/mm; 4.75 N/mm) were recorded for the samples that received a Sofreliner primer application. These values were significantly higher when the samples had no scratches and did not receive the application of Silastic Medical Adhesive Type A. Conclusions The most common type of failure was adhesive. The use of Sofreliner primer increased the bond strength between the auto-polymerized acrylic resin and the Silastic MDX 4-4210 facial silicone. PMID:23329247

  8. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Acrylate ester copolymer coating. 175.210 Section 175.210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS...

  9. A method for measuring dermal exposure to multifunctional acrylates.

    PubMed

    Surakka, J; Johnsson, S; Rosén, G; Lindh, T; Fischer, T

    1999-12-01

    UV-curable acrylates are used increasingly for coating wood surfaces in the furniture industry. One of the active components, tripropylene glycol diacrylate (TPGDA), is known to be both an allergen and irritant to the skin. Methods to measure dermal exposure to skin irritants and allergens, such as acrylates, are insufficient for exposure assessment and there is none for this compound. The aim of this investigation was to develop a skin and surface sampling method, based on tape stripping, and a gas chromatographic method for quantitative analysis for assessing occupational skin exposure to multifunctional acrylates. Twelve adhesives were tested for their efficiency to remove TPGDA and UV-coating from a glass surface, the skin of guinea pigs and human volunteers employing the tape-stripping method in order to find the best performing tape. Variables that affect removal efficiency such as the applied dose and its retention time on the skin, tape adhesion time on the skin, and the number of strippings required to detect the contaminant from the skin were studied. Fixomull tape performed the best during sampling and analysis and had the most consistent removal efficiencies for the studied substances. The average removal efficiency with a single stripping at the 2 microliters TPGDA exposed skin sites was 85% (RSD = 14.1), and for UV-resin exposed sites 63% (RSD = 20.2). The results indicated that this method can be used for measuring dermal exposure to multifunctional acrylates efficiently, accurately, and economically. This method provides a sensitive and powerful tool for the assessment of dermal exposure to multifunctional acrylates both from the skin and from other contaminated surfaces in occupational field settings. PMID:11529185

  10. Synthesis, characterization, swelling and dye adsorption properties of starch incorporated acrylic gels.

    PubMed

    Mandal, Bidyadhar; Ray, Samit Kumar

    2015-11-01

    Several hydrogels were prepared by a free radical polymerization of acrylic acid (AA), sodium acrylate (SA) and AA/hydroxy ethyl methacrylate (HEMA) in the presence of starch in water. These starch incorporated acrylic gels were prepared by varying the concentration of the initiator, monomer, crosslinker and the starch. The resulting gels were characterized by FTIR, SEM, XRD, DTA-TGA, pH at point zero charge (PZC), swelling and the diffusion in water. The gels showed high adsorption and removal% of Safranine T (ST) and Brilliant Cresyl Blue (BCB) dyes from water. The swelling and the adsorption data were fitted to different kinetic models and isotherms. Amongst the three kinds of gels, the starch incorporated sodium polyacrylate gel showed the highest adsorption of 9.7-85.3mg/L (97-61% removal) of BCB dye and 9.1-83mg/L (91-60% removal) of ST dye for a feed dye concentration of 10-140mg/L. PMID:26318665

  11. Wavelength Shifters and Interactions of EDTA with Acrylic & LAB

    NASA Astrophysics Data System (ADS)

    Mohan, Yuvraj; SNO+ Collaboration

    2014-09-01

    The SNO + experiment, an upgrade to the Sudbury Neutrino Observatory, will use linear alkyl-benzene (LAB) liquid scintillator to probe new physics, including 0 νββ decay. Event detection efficiency is heavily affected by radioactive backgrounds, two sources being Rn-222 and Po-210 daughters, some of which has become embedded in the SNO + acrylic vessel after years underground. The leading candidate for polonium leaching is Ethylenediaminetetraacetic acid (EDTA). Before deployment on-site, EDTA's effects on the mechanical integrity of acrylic must be determined. It also must not be soluble in LAB or must be removed before scintillator fill of the vessel, as its presence would result in reduced light yield due to scattering. It was found that EDTA had negligible effects on the Young's Modulus of acrylic. EDTA is also slightly soluble in LAB, but can be completely removed by rinsing with water. Additionally, the study of the light yield and alpha/beta timing profiles of two wavelength shifters - bisMSB and perylene - is critical to determining which should be added to the 0 νββ isotope (tellurium) LAB cocktail. Small-scale results hint that perylene might be better, but this is being confirmed with larger-scale tests. The SNO + experiment, an upgrade to the Sudbury Neutrino Observatory, will use linear alkyl-benzene (LAB) liquid scintillator to probe new physics, including 0 νββ decay. Event detection efficiency is heavily affected by radioactive backgrounds, two sources being Rn-222 and Po-210 daughters, some of which has become embedded in the SNO + acrylic vessel after years underground. The leading candidate for polonium leaching is Ethylenediaminetetraacetic acid (EDTA). Before deployment on-site, EDTA's effects on the mechanical integrity of acrylic must be determined. It also must not be soluble in LAB or must be removed before scintillator fill of the vessel, as its presence would result in reduced light yield due to scattering. It was found that EDTA

  12. Surface modification of nanoparticles for radiation curable acrylate clear coatings

    NASA Astrophysics Data System (ADS)

    Bauer, F.; Gläsel, H.-J.; Hartmann, E.; Bilz, E.; Mehnert, R.

    2003-08-01

    To obtain transparent, scratch and abrasion resistant coatings a high content of nanosized silica and alumina filler was embedded in radiation-curable acrylate formulations by acid catalyzed silylation using trialkoxysilanes. 29SiMAS NMR and MALDI-TOF mass spectrometry were employed to elucidate the structure of the surface-grafted methacryloxypropyl-, vinyl- and n-propyl-trimethoxysilane. In accordance with NMR findings, MALDI-TOF MS showed highly condensed oligomeric siloxanes of more than 20 monomeric silane units. A ladder-like structure of bound polysiloxanes is proposed rather than a simplified picture of tridentate silane bonding. Hence, silane coupling agents do not only modify the chemical nature of the filler surface but also strongly effect the rheological properties of the acrylate nanodispersions.

  13. Chronic pulmonary dysfunction following acute inhalation of butyl acrylate.

    PubMed

    Bhardwaj, Ravindra; Ducatman, Alan; Finkel, Mitchell S; Petsonk, Edward; Hunt, Janet; Beto, Robert J

    2012-01-01

    Butyl Acrylate (BA) (2-propionic acid; CH2 = CHCOOC4H9) is a colorless liquid commonly used in impregnation agents and adhesives. Dermal contact with BA has previously been reported to cause moderate skin irritation with skin sensitizing potential in humans. Health effects of inhalation of BA have not been previously reported. Accordingly, we document the health conditions of a bystander, first responder and landfill worker exposed to butyl acrylate (BA) released to the atmosphere following a collision and roadside spill in October 1998. Retrospective data were collected via chart review and analyzed for exposure, symptoms, physical findings and radiological, laboratory and spirometry results over a ten-year period. All three patients had similar respiratory symptoms including a dramatic hacking cough and dyspnea. Findings included abnormal pulmonary function tests and breath sounds. These data underscore the potential hazards of BA inhalational exposure and the need to wear additional protective equipment. PMID:23472539

  14. A New Process for Acrylic Acid Synthesis by Fermentative Process

    NASA Astrophysics Data System (ADS)

    Lunelli, B. H.; Duarte, E. R.; de Toledo, E. C. Vasco; Wolf Maciel, M. R.; Maciel Filho, R.

    With the synthesis of chemical products through biotechnological processes, it is possible to discover and to explore innumerable routes that can be used to obtain products of high addes value. Each route may have particular advantages in obtaining a desired product, compared with others, especially in terms of yield, productivity, easiness to separate the product, economy, and environmental impact. The purpose of this work is the development of a deterministic model for the biochemical synthesis of acrylic acid in order to explore an alternative process. The model is built-up with the tubular reactor equations together with the kinetic representation based on the structured model. The proposed process makes possible to obtain acrylic acid continuously from the sugar cane fermentation.

  15. Hydrogen bonding on the surface of poly(2-methoxyethyl acrylate).

    PubMed

    Li, Guifeng; Ye, Shen; Morita, Shigeaki; Nishida, Takuma; Osawa, Masatoshi

    2004-10-01

    Hydrogen bonding on the interface and in the bulk of a poly(2-methoxyethyl acrylate) (PMEA) thin film has been investigated by sum frequency generation, infrared reflection absorption, and Raman scattering measurements in different kinds of solutions containing hydrogen-bonding donators. These results indicate that the majority of the carbonyl groups on the PMEA surface are hydrogen-bonded with water or ethanol molecules, while the PMEA bulk is still dominated by the free carbonyl group. PMID:15453716

  16. Superselective Embolization in Posttraumatic Priapism with Glubran 2 Acrylic Glue

    SciTech Connect

    Gandini, Roberto; Spinelli, Alessio; Konda, Daniel Reale, Carlo Andrea; Fabiano, Sebastiano; Pipitone, Vincenzo; Simonetti, Giovanni

    2004-09-15

    Two patients with posttraumatic priapism underwent transcatheter embolization using microcoils, resulting in temporary penile detumescence and an apparent resolution of the artero-venous fistula. In both cases, priapism recurred 24 hours after the procedure and was successfully treated through selective transcatheter embolization of the nidus using acrylic glue (Glubran 2). The patients showed complete recovery of sexual activity within 30 days from the procedure and persistent exclusion of the artero-venous fistula after a 12-month follow-up.

  17. Permeation of multifunctional acrylates through selected protective glove materials.

    PubMed

    Renard, E P; Goydan, R; Stolki, T

    1992-02-01

    In support of the Premanufacture Notification (PMN) program of the Environmental Protection Agency's Office of Toxic Substances, the resistance of three glove materials to permeation by multifunctional acrylate compounds was evaluated through a program for the Office of Research and Development. Several recent PMN submissions relate to multifunctional acrylates and essentially no permeation data are available for this class of compounds. To better understand permeation behavior, tests were conducted with trimethylolpropane triacrylate (TMPTA), 1,6-hexanediol diacrylate (HDDA), and two mixtures of HDDA with 2-ethylhexyl acrylate (EHA). Because of the low vapor pressure and low water solubility of these compounds, the tests were conducted by using ASTM Method F739-85 with a silicone rubber sheeting material as the collection medium. Tests were performed at 20 degrees C with butyl, natural, and nitrile rubber glove materials. None of the acrylate compounds nor mixtures was found to permeate the butyl or nitrile rubber under the test conditions. Permeation through the natural rubber was observed in tests with pure HDDA, a 50% HDDA/50% EHA mixture, and a 25% HDDA/75% EHA mixture. TMPTA permeation through the natural rubber was also detected, but only in one of the triplicate tests after the 360-480 min sampling interval. For pure HDDA, the breakthrough detection time was 30-60 min and the steady-state permeation rate was 0.92 micrograms/cm2-min. For the HDDA/EHA mixtures, permeation of both mixture components was detected during the same sampling interval in each test. The breakthrough detection time was 30-60 min for the 50/50 mixture and from 15-30 to 30-60 min for the 25/75 mixture.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1543127

  18. Acrylic microspheres-based optosensor for visual detection of nitrite.

    PubMed

    Noor, Nur Syarmim Mohamed; Tan, Ling Ling; Heng, Lee Yook; Chong, Kwok Feng; Tajuddin, Saiful Nizam

    2016-09-15

    A new optosensor for visual quantitation of nitrite (NO2(-)) ion has been fabricated by physically immobilizing Safranine O (SO) reagent onto a self-adhesive poly(n-butyl acrylate) [poly(nBA)] microspheres matrix, which was synthesized via facile microemulsion UV lithography technique. Evaluation and optimization of the optical NO2(-) ion sensor was performed with a fiber optic reflectance spectrophotometer. Scanning electron micrograph showed well-shaped and smooth spherical morphology of the poly(nBA) microspheres with a narrow particles size distribution from 0.6 μm up to 1.8 μm. The uniform size distribution of the acrylic microspheres promoted homogeneity of the immobilized SO reagent molecules on the microspheres' surfaces, thereby enhanced the sensing response reproducibility (<5% RSD) with a linear range obtained from 10 to 100 ppm NO2(-) ion. The micro-sized acrylic immobilization matrix demonstrated no significant barrier for diffusion of reactant and product, and served as a good solid state ion transport medium for reflectometric nitrite determination in food samples. PMID:27080889

  19. Synthesis and characterization of a sphere-like modified chitosan and acrylate resin composite for organics absorbency

    NASA Astrophysics Data System (ADS)

    Xin, S. S.; Wang, Y. H.; Li, Q. R.; Zhang, Q.; Wang, X. P.

    2015-07-01

    In this study, the chitosan (deacetylation degree >95%) was modified with vinyltriethoxysilane (A151) and became hydrophobic. The modified chitosan and acrylate resin composite can be synthesized by butyl methacrylate (BMA), butyl acrylate (BA), poly vinyl alcoho(PVA), N,N’-methylene bisacrylamide (MBA), benzoyl peroxide (BPO), and ethyl acetate under microwave irradiation. The optimal synthetic condition was as follows: the molar ratio of BA and BMA was 1.5:1, the dosage of ethyl acetate, PVA, MBA, BPO and modified chitosan were 50 wt.%, 10 wt.%, 1.5 wt.%, 2.0 wt.% and 1.0 wt.% of monomers, respectively. The adsorption capacity of the composite for CHCl3 and CCl4 were approximate to 53 g/g and 44 g/g, respectively. The organics absorbency and regeneration of the samples were also tested, and the samples were characterized by analysis of the scanning electron microscope and simultaneous thermo gravimetric/differential thermal.

  20. Allergic contact dermatitis due to urethane acrylate in ultraviolet cured inks.

    PubMed Central

    Nethercott, J R; Jakubovic, H R; Pilger, C; Smith, J W

    1983-01-01

    Seven workers exposed to ultraviolet printing inks developed contact dermatitis. Six cases were allergic and one irritant. A urethane acrylate resin accounted for five cases of sensitisation, one of which was also sensitive to pentaerythritol triacrylate and another also to an epoxy acrylate resin. One instance of allergy to trimethylpropane triacrylate accounted for the sixth case of contact dermatitis in this group of workers. An irritant reaction is presumed to account for the dermatitis in the individual not proved to have cutaneous allergy by patch tests. In this instance trimethylpropane triacrylate was thought to be the most likely irritating agent. Laboratory investigation proved urethane acrylate to be an allergen. The results of investigations of the sensitisation potentials of urethane acrylate, methylmethacrylate, epoxy acrylate resins, toluene-2,4-diisocyanate, and other multifunctional acrylic monomers in the albino guinea pig are presented. The interpretation of such predictive tests is discussed. Images PMID:6223656

  1. Research of morphology structure and properties of bamboo charcoal acrylic fiber

    NASA Astrophysics Data System (ADS)

    Zhang, Yongjiu; Feng, Aifen

    2015-07-01

    In order to understand the properties of bamboo charcoal acrylic fiber, the tensile properties, friction properties and hygroscopicity of it, the bamboo charcoal acrylic fiber and the ordinary acrylic fiber were tested, compared and analyzed. The burning behaviors of the two kinds of fibers were observed by burning test, and their cross-sectional and longitudinal morphology was observed with scanning electron microscope (SEM). The SEM pictures showed that there are the uneven sizes of microspores on the surface of bamboo charcoal acrylic fiber and in it. It was found that the friction coefficients of the bamboo charcoal acrylic fiber are smaller and its tensile and moisture absorption are better than those of the ordinary acrylic fiber. However, there are no obvious differences of the burning behaviors between the two fibers.

  2. Radiation curing of polyester resin modified with acrylic acid and its salts

    NASA Astrophysics Data System (ADS)

    Szalińska, H.; Pietrzak, M.; Janowska, G.

    Polyester resin containing acrylic acid or its salts was cured with γ 60Co radiation. The course of curing was examined, the gel content and polymerization shrinkage were measured and also thermographic and IR absorption analyses were carried out. It was found that manganese, iron and copper acrylates inhibited the curing of resin while the remaining additives showed a slightly stimulating action. All the additives decreased the polymerization shrinkage by a factor of 2-3 and iron acrylate by as much as 8 times (up to 1%). They also increased the activation energy of the thermal decomposition of resin, and calcium, barium and copper acrylates increased the thermal stability of resin by 20 K. IR absorption spectra showed that acrylic acid and its salts reacted mainly with the monomeric component of the resin (styrene) whereas iron and copper acrylates first attacked the unsaturated bonds of the oligoester.

  3. Epoxy-acrylic core-shell particles by seeded emulsion polymerization.

    PubMed

    Chen, Liang; Hong, Liang; Lin, Jui-Ching; Meyers, Greg; Harris, Joseph; Radler, Michael

    2016-07-01

    We developed a novel method for synthesizing epoxy-acrylic hybrid latexes. We first prepared an aqueous dispersion of high molecular weight solid epoxy prepolymers using a mechanical dispersion process at elevated temperatures, and we subsequently used the epoxy dispersion as a seed in the emulsion polymerization of acrylic monomers comprising methyl methacrylate (MMA) and methacrylic acid (MAA). Advanced analytical techniques, such as scanning transmission X-ray microscopy (STXM) and peak force tapping atomic force microscopy (PFT-AFM), have elucidated a unique core-shell morphology of the epoxy-acrylic hybrid particles. Moreover, the formation of the core-shell morphology in the seeded emulsion polymerization process is primarily attributed to kinetic trapping of the acrylic phase at the exterior of the epoxy particles. By this new method, we are able to design the epoxy and acrylic polymers in two separate steps, and we can potentially synthesize epoxy-acrylic hybrid latexes with a broad range of compositions. PMID:27078740

  4. Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

    SciTech Connect

    Tajau, Rida; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik; Ibrahim, Mohammad Izzat; Yunus, Nurulhuda Mohd

    2014-02-12

    The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

  5. Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

    NASA Astrophysics Data System (ADS)

    Tajau, Rida; Ibrahim, Mohammad Izzat; Yunus, Nurulhuda Mohd; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik

    2014-02-01

    The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

  6. Theoretical study of chain transfer to solvent reactions of alkyl acrylates.

    PubMed

    Moghadam, Nazanin; Srinivasan, Sriraj; Grady, Michael C; Rappe, Andrew M; Soroush, Masoud

    2014-07-24

    This computational and theoretical study deals with chain transfer to solvent (CTS) reactions of methyl acrylate (MA), ethyl acrylate (EA), and n-butyl acrylate (n-BA) self-initiated homopolymerization in solvents such as butanol (polar, protic), methyl ethyl ketone (MEK) (polar, aprotic), and p-xylene (nonpolar). The results indicate that abstraction of a hydrogen atom from the methylene group next to the oxygen atom in n-butanol, from the methylene group in MEK, and from a methyl group in p-xylene by a live polymer chain are the most likely mechanisms of CTS reactions in MA, EA, and n-BA. Energy barriers and molecular geometries of reactants, products, and transition states are predicted. The sensitivity of the predictions to three hybrid functionals (B3LYP, X3LYP, and M06-2X) and three different basis sets (6-31G(d,p), 6-311G(d), and 6-311G(d,p)) is investigated. Among n-butanol, sec-butanol, and tert-butanol, tert-butanol has the highest CTS energy barrier and the lowest rate constant. Although the application of the conductor-like screening model (COSMO) does not affect the predicted CTS kinetic parameter values, the application of the polarizable continuum model (PCM) results in higher CTS energy barriers. This increase in the predicted CTS energy barriers is larger for butanol and MEK than for p-xylene. The higher rate constants of chain transfer to n-butanol reactions compared to those of chain transfer to MEK and p-xylene reactions suggest the higher CTS reactivity of n-butanol. PMID:24971646

  7. Comparison between an Acrylic Splint Herbst and an Acrylic Splint Miniscrew-Herbst for Mandibular Incisors Proclination Control

    PubMed Central

    Manni, Antonio; Pasini, Marco; Nuzzo, Claudio; Grassi, Felice Roberto

    2014-01-01

    Aim. The aim of this study is to compare dental and skeletal effects produced by an acrylic splint Herbst with and without skeletal anchorage for correction of dental class II malocclusion. Methods. The test group was formed by 14 patients that were treated with an acrylic splint miniscrew-Herbst; miniscrews were placed between mandibular second premolars and first molars; controls also consisted of 14 subjects that were treated with an acrylic splint Herbst and no miniscrews. Cephalometric measurements before and after Herbst treatment were compared. The value of α for significance was set at 0.05. Results. All subjects from both groups were successfully treated to a bilateral Class I relationship; mean treatment time was 8,1 months in the test group and 7.8 in the controls. Several variables did not have a statistical significant difference between the two groups. Some of the variables, instead, presented a significant difference such as incisor flaring, mandibular bone base position, and skeletal discrepancy. Conclusions. This study showed that the Herbst appliance associated to miniscrews allowed a better control of the incisor flaring with a greater mandibular skeletal effect. PMID:24963293

  8. N-Butyl acrylate polymer composition for solar cell encapsulation and method

    NASA Technical Reports Server (NTRS)

    Gupta, Amitava (Inventor); Ingham, John D. (Inventor); Yavrouian, Andre H. (Inventor)

    1983-01-01

    A polymer syrup for encapsulating solar cell assemblies. The syrup includes uncrosslinked poly(n-butyl)acrylate dissolved in n-butyl acrylate monomer. Preparation of the poly(n-butyl)acrylate and preparation of the polymer syrup is disclosed. Methods for applying the polymer syrup to solar cell assemblies as an encapsulating pottant are described. Also included is a method for solar cell construction utilizing the polymer syrup as a dual purpose adhesive and encapsulating material.

  9. Quartz crystal microbalance and infrared reflection absorption spectroscopy characterization of bisphenol A absorption in the poly(acrylate) thin films.

    PubMed

    Li, Guifeng; Morita, Shigeaki; Ye, Shen; Tanaka, Masaru; Osawa, Masatoshi

    2004-02-01

    The absorption process of bisphenol A (BPA) in a number of poly(acrylate) thin films, such as poly(2-methoxyethyl acrylate) (PMEA), poly(ethyl acrylate) (PEA), poly(n-butyl methacrylate) (PBMA), and poly(methyl methacrylate) (PMMA), has been investigated by quartz crystal microbalance (QCM) and infrared reflection absorption spectroscopy (IRRAS) measurements. Both QCM and IRRAS measurements show that the BPA molecules absorb in PMEA, PEA, and PBMA thin films but not in PMMA thin film. The differences in the BPA absorption behavior are mainly attributed to the difference in the glass transition temperature (T(g)) between these polymers. This absorption behavior also depends on the BPA concentration and polymer film thickness. Furthermore, IRRAS characterization demonstrates that the hydrogen bonding is formed between the hydroxyl group in BPA and the carbonyl group in the poly(acrylate) thin films. BPA molecule absorbed in these polymer thin films can be removed by ethanol rinse treatment. By optimizing experimental conditions for the QCM electrode modified by PMEA thin film, detection limitation of approximately 1 ppb for BPA can be realized by the in situ QCM measurement. This method is expected to be a sensitive in situ detection way for trace BPA in the environmental study. PMID:14750877

  10. Acrylic fragmentation in total hip replacements and its biological consequences.

    PubMed

    Jasty, M; Jiranek, W; Harris, W H

    1992-12-01

    Loosening of total joint prostheses is in part related to the fragmentation of the acrylic cement mantle surrounding the prosthesis and the biologic consequences to the particulate acrylic. Fractographic studies of femoral cement mantles retrieved at revision surgery and autopsy showed frequent fractures in varying stages of development in the cement and wear at the fracture surfaces. Defects in the cement mantle, thin mantles, sharp corners on the prosthesis, separation at the cement mantle interface, and pores in the cement were frequently associated with cement fractures. The progressive fractures and wear led to the liberation of particulate acrylic debris into the surrounding tissues. The tissues at the bone-cement interface removed at revision surgery showed that a macrophage, giant-cell foreign-body granulomatous reaction occurs in response to the particulate, but not bulk cement. This tissue can produce a variety of chemical mediators of inflammation and bone resorption, and can resorb bone in organ cultures. A granulomatous tissue reaction with a very similar appearance can be produced in experimental animals using particulate-form polymethylmethacrylate (PMMA), but not the bulk form of PMMA. The tissue reaction is not mediated by the classic cell or humeral immune mechanisms. Subcutaneous injection of particulate PMMA powder into fully immunocompetent C3Hf/SED mice as well as three strains of mice with progressive immunologic deficiencies (nude/nude, SCID, and triple deficient Nu-bg-XID/SED mice) led to a foreign-body reaction in all strains at five weeks as shown by histologic and immunohistochemical examination despite the differences in immune deficiency. This, along with the scarcity of lymphocytes in the human tissues, suggests that the biologic reactions to fragmented cement can be produced and sustained by nonimmune phagocytosis and activation by macrophages and giant cells without significant contribution by the immune system. PMID:1446427

  11. Anomerization of Acrylated Glucose During Traveling Wave Ion Mobility Spectrometry

    NASA Astrophysics Data System (ADS)

    Chendo, Christophe; Moreira, Guillaume; Tintaru, Aura; Posocco, Paola; Laurini, Erik; Lefay, Catherine; Gigmes, Didier; Viel, Stéphane; Pricl, Sabrina; Charles, Laurence

    2015-09-01

    Anomerization of simple sugars in the liquid phase is known as an acid- and base-catalyzed process, which highly depends on solvent polarity. This reaction is reported here to occur in the gas phase, during traveling wave ion mobility spectrometry (TWIMS) experiments aimed at separating α- and β-anomers of penta-acrylated glucose generated as ammonium adducts in electrospray ionization. This compound was available in two samples prepared from glucose dissolved in solvents of different polarity, namely tetrahydrofuran (THF) and N,N-dimethylacetamide (DMAC), and analyzed by electrospray tandem mass spectrometry (ESI-MS/MS) as well as traveling wave ion mobility (ESI-TWIMS-MS). In MS/MS, an anchimerically-assisted process was found to be unique to the electrosprayed α-anomer, and was only observed for the THF sample. In ESI-TWIMS-MS, a signal was measured at the drift time expected for the α-anomer for both the THF and DMAC samples, in apparent contradiction to the MS/MS results, which indicated that the α-anomer was not present in the DMAC sample. However, MS/MS experiments performed after TWIMS separation revealed that ammonium adducts of the α-anomer produced from each sample, although exhibiting the same collision cross section, were clearly different. Indeed, while the α-anomer actually present in the THF sample was electrosprayed with the ammonium adducted at the C2 acrylate, its homologue only observed when the DMAC sample was subjected to TWIMS hold the adducted ammonium at the C1 acrylate. These findings were explained by a β/α inter-conversion upon injection in the TWIMS cell, as supported by theoretical calculation and dynamic molecular modeling.

  12. Softec HD hydrophilic acrylic intraocular lens: biocompatibility and precision

    PubMed Central

    Espandar, Ladan; Sikder, Shameema; Moshirfar, Majid

    2011-01-01

    Intraocular lens development is driven by higher patient expectations for ideal visual outcomes. The recently US Food and Drug Administration-approved Softec HD™ lens is an aspheric, hydrophilic acrylic intraocular lens (IOL). The hydrophilic design of the lens is optimized to address dysphotopsia while maintaining biocompatibility, optical clarity, resistance to damage, and resistance to biocontamination. Aspheric lenses decrease postoperative spherical aberration. The addition of the Softec lens provides clinicians with another option for IOL placement; however, randomized comparative studies of this lens to others already on the market remain to be completed. PMID:21311658

  13. Lactate and Acrylate Metabolism by Megasphaera elsdenii under Batch and Steady-State Conditions

    PubMed Central

    Prabhu, Rupal; Altman, Elliot

    2012-01-01

    The growth of Megasphaera elsdenii on lactate with acrylate and acrylate analogues was studied under batch and steady-state conditions. Under batch conditions, lactate was converted to acetate and propionate, and acrylate was converted into propionate. Acrylate analogues 2-methyl propenoate and 3-butenoate containing a terminal double bond were similarly converted into their respective saturated acids (isobutyrate and butyrate), while crotonate and lactate analogues 3-hydroxybutyrate and (R)-2-hydroxybutyrate were not metabolized. Under carbon-limited steady-state conditions, lactate was converted to acetate and butyrate with no propionate formed. As the acrylate concentration in the feed was increased, butyrate and hydrogen formation decreased and propionate was increasingly generated, while the calculated ATP yield was unchanged. M. elsdenii metabolism differs substantially under batch and steady-state conditions. The results support the conclusion that propionate is not formed during lactate-limited steady-state growth because of the absence of this substrate to drive the formation of lactyl coenzyme A (CoA) via propionyl-CoA transferase. Acrylate and acrylate analogues are reduced under both batch and steady-state growth conditions after first being converted to thioesters via propionyl-CoA transferase. Our findings demonstrate the central role that CoA transferase activity plays in the utilization of acids by M. elsdenii and allows us to propose a modified acrylate pathway for M. elsdenii. PMID:23023753

  14. Control of contamination of radon-daughters in the DEAP-3600 acrylic vessel

    NASA Astrophysics Data System (ADS)

    Jillings, Chris; DEAP Collaboration

    2013-08-01

    DEAP-3600 is a 3600kg single-phase liquid-argon dark matter detector under construction at SNOLAB with a sensitivity of 10-46cm2 for a 100 GeV WIMP. The argon is held an an acrylic vessel coated with wavelength-shifting 1,1,4,4-tetraphenyl-1,3-butadiene (TPB). Acrylic was chosen because it is optically transparent at the shifted wavelength of 420 nm; an effective neutron shield; and physically strong. With perfect cleaning of the acrylic surface before data taking the irreducible background is that from bulk 210Pb activity that is near the surface. To achieve a background rate of 0.01 events in the 1000-kg fiducial volume per year of exposure, the allowed limit of Pb-210 in the bulk acrylic is 31 mBq/tonne (= 1.2 × 10-20g/g). We discuss how pure acrylic was procured and manufactured into a complete vessel paying particular attention to exposure to radon during all processes. In particular field work at the acrylic panel manufacturer, RPT Asia, and acrylic monomer supplier, Thai MMA Co. Ltd, in Thailand is described. The increased diffusion of radon during annealing the acrylic at 90C as well as techniques to mitigate against this are described.

  15. Preparation and properties of acrylic resin coating modified by functional graphene oxide

    NASA Astrophysics Data System (ADS)

    Dong, Rui; Liu, Lili

    2016-04-01

    To improve the dispersion and the strength of filler-matrix interface in acrylic resin, the functional graphene oxide (FGO) was obtained by surface modification of graphene oxide (GO) by γ-methacryloxypropyl trimethoxysilane (KH-570) and then the acrylic nanocomposites containing different loadings of GO and FGO were prepared. The structure, morphology and dispersion/exfoliation of the FGO were characterized by XRD, FT-IR, Raman, XPS, SEM and TEM. The results demonstrated that the KH-570 was successfully grafted onto the surface of GO sheets. Furthermore, the corresponding thermal, mechanical and chemical resistance properties of the acrylic nanocomposites filled with the FGO were studied and compared with those of neat acrylic and GO/acrylic nanocomposites. The results revealed that the loading of FGO effectively enhanced various properties of acrylic resin. These findings confirmed that the dispersion and interfacial interaction were greatly improved by incorporation of FGO, which might be the result of covalent bonds between the FGO and the acrylic matrix. This work demonstrates an in situ polymerization method to construct a flexible interphase structure, strong interfacial interaction and good dispersion of FGO in acrylic nanocomposites, which can reinforce the polymer properties and be applied in research and industrial areas.

  16. 21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... polymer units derived from methyl acrylate. (b) The finished food-contact article, when extracted with the... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ethylene-methyl acrylate copolymer resins. 177.1340 Section 177.1340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  17. Synthesis of Radiation Curable Palm Oil-Based Epoxy Acrylate: NMR and FTIR Spectroscopic Investigations.

    PubMed

    Salih, Ashraf M; Ahmad, Mansor Bin; Ibrahim, Nor Azowa; Dahlan, Khairul Zaman Hj Mohd; Tajau, Rida; Mahmood, Mohd Hilmi; Yunus, Wan Md Zin Wan

    2015-01-01

    Over the past few decades, there has been an increasing demand for bio-based polymers and resins in industrial applications, due to their potential lower cost and environmental impact compared with petroleum-based counterparts. The present research concerns the synthesis of epoxidized palm oil acrylate (EPOLA) from an epoxidized palm oil product (EPOP) as environmentally friendly material. EPOP was acrylated by acrylic acid via a ring opening reaction. The kinetics of the acrylation reaction were monitored throughout the reaction course and the acid value of the reaction mixture reached 10 mg KOH/g after 16 h, indicating the consumption of the acrylic acid. The obtained epoxy acrylate was investigated intensively by means of FTIR and NMR spectroscopy, and the results revealed that the ring opening reaction was completed successfully with an acrylation yield about 82%. The UV free radical polymerization of EPOLA was carried out using two types of photoinitiators. The radiation curing behavior was determined by following the conversion of the acrylate groups. The cross-linking density and the hardness of the cured EPOLA films were measured to evaluate the effect of the photoinitiator on the solid film characteristics, besides, the thermal and mechanical properties were also evaluated. PMID:26248072

  18. 40 CFR 721.10389 - Styrene, copolymer with acrylic acid, salt with alkoxylated alkenylamine (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Styrene, copolymer with acrylic acid... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10389 Styrene, copolymer with acrylic... subject to reporting. (1) The chemical substance identified generically as styrene, copolymer with...

  19. 40 CFR 721.10530 - Acrylate manufacture byproduct distillation residue (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... distillation residue (generic). 721.10530 Section 721.10530 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10530 Acrylate manufacture byproduct distillation... substance is identified generically as acrylate manufacture byproduct distillation residue (PMN P-12-87)...

  20. 40 CFR 721.10530 - Acrylate manufacture byproduct distillation residue (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... distillation residue (generic). 721.10530 Section 721.10530 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10530 Acrylate manufacture byproduct distillation... substance is identified generically as acrylate manufacture byproduct distillation residue (PMN P-12-87)...

  1. 21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .../methyl methacrylate polymers. The vinylidene chloride/methyl acrylate/methyl methacrylate polymers (CAS... methacrylate polymers consist of basic polymers produced by the copolymerization of vinylidene chloride/methyl acrylate/methyl methacrylate such that the basic polymers or the finished food-contact articles meet...

  2. Control of contamination of radon-daughters in the DEAP-3600 acrylic vessel

    SciTech Connect

    Jillings, Chris; Collaboration: DEAP Collaboration; and others

    2013-08-08

    DEAP-3600 is a 3600kg single-phase liquid-argon dark matter detector under construction at SNOLAB with a sensitivity of 10{sup −46}cm{sup 2} for a 100 GeV WIMP. The argon is held an an acrylic vessel coated with wavelength-shifting 1,1,4,4-tetraphenyl-1,3-butadiene (TPB). Acrylic was chosen because it is optically transparent at the shifted wavelength of 420 nm; an effective neutron shield; and physically strong. With perfect cleaning of the acrylic surface before data taking the irreducible background is that from bulk {sup 210}Pb activity that is near the surface. To achieve a background rate of 0.01 events in the 1000-kg fiducial volume per year of exposure, the allowed limit of Pb-210 in the bulk acrylic is 31 mBq/tonne (= 1.2 × 10{sup −20}g/g). We discuss how pure acrylic was procured and manufactured into a complete vessel paying particular attention to exposure to radon during all processes. In particular field work at the acrylic panel manufacturer, RPT Asia, and acrylic monomer supplier, Thai MMA Co. Ltd, in Thailand is described. The increased diffusion of radon during annealing the acrylic at 90C as well as techniques to mitigate against this are described.

  3. Plasma polymerization of acrylic acid onto polystyrene by cyclonic plasma at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Chang, Yi-Jan; Lin, Chin-Ho; Huang, Chun

    2016-01-01

    The cyclonic atmospheric-pressure plasma is developed for chamberless deposition of poly(acrylic acid) film from argon/acrylic acid mixtures. The photoemission plasma species in atmospheric-pressure plasma polymerization was identified by optical emission spectroscopy (OES). The OES diagnosis data and deposition results indicated that in glow discharge, the CH and C2 species resulted from low-energy electron-impact dissociation that creates deposition species, but the strong CO emission lines are related to nondeposition species. The acrylic acid flow rate is seen as the key factor affecting the film growth. The film surface analysis results indicate that a smooth, continuous, and uniform surface of poly(acrylic acid) films can be formed at a relatively low plasma power input. This study reveals the potential of chamberless film growth at atmospheric pressure for large-area deposition of poly(acrylic acid) films.

  4. Influence of Sea Water Aging on the Mechanical Behaviour of Acrylic Matrix Composites

    NASA Astrophysics Data System (ADS)

    Davies, P.; Le Gac, P.-Y.; Le Gall, M.

    2016-07-01

    A new matrix resin was recently introduced for composite materials, based on acrylic resin chemistry allowing standard room temperature infusion techniques to be used to produce recyclable thermoplastic composites. This is a significant advance, particularly for more environmentally-friendly production of large marine structures such as boats. However, for such applications it is essential to demonstrate that composites produced with these resins resist sea water exposure in service. This paper presents results from a wet aging study of unreinforced acrylic and glass and carbon fibre reinforced acrylic composites. It is shown that the acrylic matrix resin is very stable in seawater, showing lower property losses after seawater aging than those of a commonly-used epoxy matrix resin. Carbon fibre reinforced acrylic also shows good property retention after aging, while reductions in glass fibre reinforced composite strengths suggest that specific glass fibre sizing may be required for optimum durability.

  5. The study of synthesis and photocuring behaviors of organic silicon modified methylacrylate and acrylate

    NASA Astrophysics Data System (ADS)

    Wang, Si-yuan; Zou, Ying-quan

    2012-03-01

    Ten different silicon-containing methyl acrylate and acrylate monomers were synthesized by the substitution reaction of chlorosilanes or chlorosiloxanes with 2-Hydroxyethyl methacrylate or 2-Hydroxyethyl acrylate. Using triethylamine as the catalytic agent, tetrahydrofuran as the solvent, pure products can be obtained with one-step reaction after reduced pressure distillation or column chromatography via controlling raw ratio and reaction time. In this study, one to four silicon contained methyl acrylate and acrylate monomers were synthesized with simple methd and high yield. Monomers' properties were characterized through IR, 1H-NMR, 13C-NMR and their viscosity and thermostability were also characterized. The polymers' have good performance on UV-curing and low surface energy.

  6. Characteristics and mechanisms of acrylate polymer damage to maize seedlings.

    PubMed

    Chen, Xian; Mao, Xiaoyun; Lu, Qin; Liao, Zongwen; He, Zhenli

    2016-07-01

    Superabsorbent acrylate polymers (SAPs) have been widely used to maintain soil moisture in agricultural management, but they may cause damage to plants, and the mechanisms are not well understood. In this study, seed germination, soil pot culture, hydroponic experiments, and SAPs degradation were conducted to investigate damage characteristics and mechanisms associated with SAPs application. The Results showed that SAPs inhibited maize growth and altered root morphology (irregular and loose arrangement of cells and breakage of cortex parenchyma), and the inhibitory effects were enhanced at higher SAPs rates. After 1h SAP hydrogels treatment, root malondialdehyde (MDA) content was significantly increased, while superoxide dismutase (SOD) and catalase (CAT) content were significantly decreased. Hydroponics experiment indicated that root and shoot growth was inhibited at 2.5mgL(-1) acrylic acid (AA), and the inhibition was enhanced with increasing AA rates. This effect was exacerbated by the presence of Na(+) at a high concentration in the hydrogels. Release and degradation of AA were enhanced at higher soil moisture levels. A complete degradation of AA occurred between 15 and 20 days after incubation (DAI), but it took longer for Na(+) concentration to decrease to a safe level. These results indicate that high concentration of both AA and Na(+) present in the SAPs inhibits plant growth. The finding of this study may provide a guideline for appropriate application of SAPs in agriculture. PMID:27057990

  7. [New acrylic resins with very low residual monomer].

    PubMed

    Ohe, Y; Kadoma, Y; Imai, Y

    1989-07-01

    New experimental acrylic resins were prepared by polymerization of MMA in the presence of vinylidene fluoride/hexafluoropropylene copolymer. The amount of residual monomer in the resins prepared by visible light curing, cold curing, and heat curing, at various polymer/monomer ratios, was measured and compared with the usual MMA/PMMA resin. In the visible light cured resins containing 60 or 70 wt% of the fluoropolymer, the amount of residual monomer was less than 0.1%. In the cold cured resins, the amount of residual monomer was very low: 0.2% and 0.7% for the resins containing 70 and 60 wt% of the polymer, respectively. These values were comparable to the usual heat cured MMA/PMMA resins. In the heat cured resins, the amount of residual monomer was the lowest; less than 0.1%, even in the resin consisting of 50 wt% polymer. Thus, we prepared new acrylic resins with much less residual monomer than the usual MMA/PMMA resins. PMID:2491165

  8. Solventless, radiation-cured acrylate formulations for magnetic tape manufacturer

    NASA Astrophysics Data System (ADS)

    Huh, Jin Young

    Significant progress was made toward identifying a binder materials package that would enable a solventless magnetic tape manufacturing process that would eliminate the possibility of air pollution. Mixtures of commercial acrylate monomers and acrylate-terminated urethane oligomers gave electron beam cured films with good tensile properties. The binder polymers suffered no significant decrease in tensile strength after accelerated aging at 60°C and 90% relative humidity. Commercial magnetic particles were treated with silane coupling agents, which enabled the preparation of dispersions with rheological properties that approach those of conventional solvent-based formulations. A methacylate functionalized silane coupling agent provided the best rheological properties. Branched silane coupling agents provided steric barriers against magnetic attraction forces between particles. Magnetic particles acted as reinforcing fillers in a magnetic tape. Silane treated particles provided 20--30% increase in tensile strength and Young's modulus over untreated particles. UV could cure the magnetic tape containing 70 wt% particles. This was done with the help of silane coupling agents which acted as dispersion stabilizing agents.

  9. Water structure and blood compatibility of poly(tetrahydrofurfuryl acrylate).

    PubMed

    Mochizuki, Akira; Hatakeyama, Tatsuko; Tomono, Yuka; Tanaka, Masaru

    2009-01-01

    We previously reported that poly(2-methoxyethyl acrylate) (PMEA), which has excellent blood compatibility, contains a large amount of freezing bound water. In order to confirm the role of freezing bound water in determining blood compatibility, poly(tetrahydrofurfuryl acrylate) (PTHFA) was newly synthesized and the thermal properties of water in PTHFA were investigated by differential scanning calorimetry (DSC), as freezing bound water was observed as cold crystallization in DSC heating curves. In addition, the blood compatibility of PTHFA, including activations of platelets, the coagulation system and the complement system, was investigated. The temperature of cold crystallization of water in PTHFA was higher than that of water in PMEA; moreover, the amount of freezing bound water in PTHFA was smaller than that in PMEA. The effect of freezing bound water on blood compatibility was investigated by comparing PTHFA, PMEA, poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(2-methoxyethyl methacrylate) (PMEMA). The latter two samples showed no cold crystallization. Activations of platelets, the coagulation system and the complement system were enhanced in the following order: PMEA < PHEMA < PTHFA < PMEMA, PMEA < PMEMA < PTHFA < PHEMA and PMEA < PTHFA < PMEMA < PHEMA, respectively. The above results were reasonably explained by the amount and/or the stability of freezing bound water. PMID:19323878

  10. Patterned biofunctional poly(acrylic acid) brushes on silicon surfaces.

    PubMed

    Dong, Rong; Krishnan, Sitaraman; Baird, Barbara A; Lindau, Manfred; Ober, Christopher K

    2007-10-01

    Protein patterning was carried out using a simple procedure based on photolithography wherein the protein was not subjected to UV irradiation and high temperatures or contacted with denaturing solvents or strongly acidic or basic solutions. Self-assembled monolayers of poly(ethylene glycol) (PEG) on silicon surfaces were exposed to oxygen plasma through a patterned photoresist. The etched regions were back-filled with an initiator for surface-initiated atom transfer radical polymerization (ATRP). ATRP of sodium acrylate was readily achieved at room temperature in an aqueous medium. Protonation of the polymer resulted in patterned poly(acrylic acid) (PAA) brushes. A variety of biomolecules containing amino groups could be covalently tethered to the dense carboxyl groups of the brush, under relatively mild conditions. The PEG regions surrounding the PAA brush greatly reduced nonspecific adsorption. Avidin was covalently attached to PAA brushes, and biotin-tagged proteins could be immobilized through avidin-biotin interaction. Such an immobilization method, which is based on specific interactions, is expected to better retain protein functionality than direct covalent binding. Using biotin-tagged bovine serum albumin (BSA) as a model, a simple strategy was developed for immobilization of small biological molecules using BSA as linkages, while BSA can simultaneously block nonspecific interactions. PMID:17880179

  11. Desorption of biocides from renders modified with acrylate and silicone.

    PubMed

    Styszko, Katarzyna; Bollmann, Ulla E; Wangler, Timothy P; Bester, Kai

    2014-01-01

    Biocides are used in the building industry to prevent algal, bacterial and fungal growth on polymericrenders and thus to protect buildings. However, these biocides are leached into the environment. To better understand this leaching, the sorption/desorption of biocides in polymeric renders was assessed. In this study the desorption constants of cybutryn, carbendazim, iodocarb, isoproturon, diuron, dichloro-N-octylisothiazolinone and tebuconazole towards acrylate and silicone based renders were assessed at different pH values. At pH 9.5 (porewater) the constants for an acrylate based render varied between 8 (isoproturon) and 9634 (iodocarb) and 3750 (dichloro-N-octylisothiazolinone), respectively. The values changed drastically with pH value. The results for the silicone based renders were in a similar range and usually the compounds with high sorption constants for one polymer also had high values for the other polymer. Comparison of the octanol water partitioning constants (Kow) with the render/water partitioning constants (Kd) revealed similarities, but no strong correlation. Adding higher amounts of polymer to the render material changed the equilibria for dichloro-N-octylisothiazolinone, tebuconazole, cybutryn, carbendazim but not for isoproturon and diuron. PMID:24059976

  12. Characterization of bioactive RGD peptide immobilized onto poly(acrylic acid) thin films by plasma polymerization

    NASA Astrophysics Data System (ADS)

    Seo, Hyun Suk; Ko, Yeong Mu; Shim, Jae Won; Lim, Yun Kyong; Kook, Joong-Ki; Cho, Dong-Lyun; Kim, Byung Hoon

    2010-11-01

    Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH2 of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants.

  13. Synthesis of graft copolymers based on poly(2-methoxyethyl acrylate) and investigation of the associated water structure.

    PubMed

    Javakhishvili, Irakli; Tanaka, Masaru; Ogura, Keiko; Jankova, Katja; Hvilsted, Søren

    2012-02-27

    Graft copolymers composed of poly(2-methoxyethyl acrylate) are prepared employing controlled radical polymerization techniques. Linear backbones bearing atom transfer radical polymerization (ATRP) initiating sites are obtained by reversible addition-fragmentation chain transfer copolymerization of 2-methoxyethyl acrylate (MEA) and 2-(bromoisobutyryloxy)ethyl methacrylate (Br(i) BuEMA) as well as 2-hydroxyethyl methacrylate and Br(i) BuEMA in a controlled manner . MEA is then grafted from the linear macroinitiators by Cu (I)-mediated ATRP. Fairly high molecular weights (>120 000 Da) and low polydispersity indices (1.17-1.38) are attained. Thermal investigations of the graft copolymers indicate the presence of the freezing bound water, and imply that the materials may exhibit blood compatibility. PMID:22271568

  14. Asymmetric aza-Morita-Baylis-Hillman reactions of chiral N-phosphonyl imines with acrylates via GAP chemistry/technology.

    PubMed

    Yang, Bing; Ji, Xiaozhou; Xue, Yunsheng; Zhang, Haowei; Shen, Minxing; Jiang, Bo; Li, Guigen

    2016-07-01

    Chiral N-phosphonyl imines have been proven to be efficient electrophilic acceptors for asymmetric aza-Morita-Baylis-Hillman (aza-MBH) reactions with acrylates under convenient conditions. Thirty examples of β-amino acrylates were generated in high yields (up to 99.4%) and diastereoselectivity (up to >99 : 1 dr) in an atom-economical fashion. The synthesis was proved to follow the GAP (group-assisted purification) chemistry, i.e., the pure products can be obtained simply by washing the crude products with hexane/ethyl acetate (v/v, 10/1) without the use of chromatography or recrystallization. DFT calculations were also conducted to support an asymmetric induction model accounting for high diastereoselectivity. PMID:27232108

  15. Investigation of fluorinated (Meth)acrylate monomers and macromonomers suitable for a hydroxy-containing acrylate monomer in UV nanoimprinting.

    PubMed

    Ito, Shunya; Kaneko, Shu; Yun, Cheol Min; Kobayashi, Kei; Nakagawa, Masaru

    2014-06-24

    We investigated reactive fluorinated (meth)acrylate monomers and macromonomers that caused segregation at the cured resin surface of a viscous hydroxy-containing monomer, glycerol 1,3-diglycerolate diacrylate (GDD), and decreased the demolding energy in ultraviolet (UV) nanoimprinting with spin-coated films under a condensable alternative chlorofluorocarbon gas atmosphere. The X-ray photoelectron spectroscopy and contact angle measurements used to determine the surface free energy suggested that a nonvolatile silicone-based methacrylate macromonomer with fluorinated alkyl groups segregated at the GDD-based cured resin surface and decreased the surface free energy, while fluorinated acrylate monomers hardly decreased the surface free energy because of their evaporation during the annealing of the spin-coated films. The average demolding energy of GDD-based cured resins with the macromonomer having fluorinated alkyl groups was smaller than that with the macromonomer having hydrocarbon alkyl groups. The fluorinated alkyl groups were responsible for decreasing the demolding energy rather than the polysiloxane main chains. We demonstrated that the GDD-based UV-curable resin with the fluorinated silicone-based macromonomer was suitable for step-and-repeat UV nanoimprinting with a bare silica mold, in addition to silica molds treated by chemical vapor surface modification with trifluoro-1,1,2,2-tetrahydropropyltrimethoxysilane (FAS3) and tridecafluoro-1,1,2,2-tetrahydrooctyltrimethoxysilane (FAS13). PMID:24892792

  16. An ORMOSIL-Containing Orthodontic Acrylic Resin with Concomitant Improvements in Antimicrobial and Fracture Toughness Properties

    PubMed Central

    Rueggeberg, Frederick A.; Niu, Li-na; Mettenberg, Donald; Yiu, Cynthia K. Y.; Blizzard, John D.; Wu, Christine D.; Mao, Jing; Drisko, Connie L.; Pashley, David H.; Tay, Franklin R.

    2012-01-01

    Global increase in patients seeking orthodontic treatment creates a demand for the use of acrylic resins in removable appliances and retainers. Orthodontic removable appliance wearers have a higher risk of oral infections that are caused by the formation of bacterial and fungal biofilms on the appliance surface. Here, we present the synthetic route for an antibacterial and antifungal organically-modified silicate (ORMOSIL) that has multiple methacryloloxy functionalities attached to a siloxane backbone (quaternary ammonium methacryloxy silicate, or QAMS). By dissolving the water-insoluble, rubbery ORMOSIL in methyl methacrylate, QAMS may be copolymerized with polymethyl methacrylate, and covalently incorporated in the pressure-processed acrylic resin. The latter demonstrated a predominantly contact-killing effect on Streptococcus mutans ATCC 36558 and Actinomyces naselundii ATCC 12104 biofilms, while inhibiting adhesion of Candida albicans ATCC 90028 on the acrylic surface. Apart from its favorable antimicrobial activities, QAMS-containing acrylic resins exhibited decreased water wettability and improved toughness, without adversely affecting the flexural strength and modulus, water sorption and solubility, when compared with QAMS-free acrylic resin. The covalently bound, antimicrobial orthodontic acrylic resin with improved toughness represents advancement over other experimental antimicrobial acrylic resin formulations, in its potential to simultaneously prevent oral infections during appliance wear, and improve the fracture resistance of those appliances. PMID:22870322

  17. Gel polymer electrolytes based on nanofibrous polyacrylonitrile–acrylate for lithium batteries

    SciTech Connect

    Kim, Dul-Sun; Woo, Jang Chang; Youk, Ji Ho; Manuel, James; Ahn, Jou-Hyeon

    2014-10-15

    Graphical abstract: - Highlights: • Nanofibrous polyacrylonitrile–acrylate membranes were prepared by electrospinning. • Trimethylolpropane triacrylate was used as a crosslinking agent of fibers. • The GPE based on PAN–acrylate (1/0.5) showed good electrochemical properties. - Abstract: Nanofibrous membranes for gel polymer electrolytes (GPEs) were prepared by electrospinning a mixture of polyacrylonitrile (PAN) and trimethylolpropane triacrylate (TMPTA) at weight ratios of 1/0.5 and 1/1. TMPTA is used to achieve crosslinking of fibers thereby improving mechanical strength. The average fiber diameters increased with increasing TMPTA concentration and the mechanical strength was also improved due to the enhanced crosslinking of fibers. GPEs based on electrospun membranes were prepared by soaking them in a liquid electrolyte of 1 M LiPF{sub 6} in ethylene carbonate (EC)/dimethyl carbonate (DMC) (1:1, v/v). The electrolyte uptake and ionic conductivity of GPEs based on PAN and PAN–acrylate (weight ratio; 1/1 and 1/0.5) were investigated. Ionic conductivity of GPEs based on PAN–acrylate was the highest for PAN/acrylate (1/0.5) due to the proper swelling of fibers and good affinity with liquid electrolyte. Both GPEs based on PAN and PAN–acrylate membranes show good oxidation stability, >5.0 V vs. Li/Li{sup +}. Cells with GPEs based on PAN–acrylate (1/0.5) showed remarkable cycle performance with high initial discharge capacity and low capacity fading.

  18. Solvent effects on acrylate kp in organic media?-A systematic PLP-SEC study.

    PubMed

    Haehnel, Alexander P; Wenn, Benjamin; Kockler, Katrin; Bantle, Tobias; Misske, Andrea M; Fleischhaker, Friederike; Junkers, Thomas; Barner-Kowollik, Christopher

    2014-12-01

    The Arrhenius parameters of the propagation rate coefficient, kp , are determined employing high-frequency pulsed laser polymerization-size exclusion chromatography (PLP-SEC) for the homologous series of five linear alkyl acrylates (i.e., methyl acrylate (MA), butyl acrylate (BA), dodecyl acrylate (DA), stearyl acrylate (SA), and behenyl acrylate (BeA)) in 1 m solution in butyl acetate (BuAc) as well as in toluene. The comparison of the obtained kp values with the literature known values for bulk demonstrates that no significant solvent influence neither in BuAc nor in toluene on the propagation reaction compared to bulk is detectable. Concomitantly, the kp values in toluene and in BuAc solution display a similar increase with increasing number of C-atoms in the ester side chain as was previously reported for the bulk systems. These findings are in clear contrast to earlier studies, which report a decrease of kp with increasing ester side chain length in toluene. The additional investigation of the longest and shortest ester side chain acrylate (i.e., BeA and MA) over the entire experimentally available concentration range at one temperature (i.e., 50 °C) does not reveal any general concentration dependence and all observed differences in the kp are within the experimental error. PMID:25363291

  19. Production of 3-hydroxypropionic acid from acrylic acid by newly isolated rhodococcus erythropolis LG12.

    PubMed

    Lee, Sang-Hyun; Park, Si Jae; Park, Oh-Jin; Cho, Junhyeong; Rhee, Joo Won

    2009-05-01

    A novel microorganism, designated as LG12, was isolated from soil based on its ability to use acrylic acid as the sole carbon source. An electron microscopic analysis of its morphological characteristics and phylogenetic classification by 16S rRNA homology showed that the LG12 strain belongs to Rhodococcus erythropolis. R. erythropolis LG12 was able to metabolize a high concentration of acrylic acid (up to 40 g/l). In addition, R. erythropolis LG12 exhibited the highest acrylic acid-degrading activity among the tested microorganisms, including R. rhodochrous, R. equi, R. rubber, Candida rugosa, and Bacillus cereus. The effect of the culture conditions of R. erythropolis LG12 on the production of 3-hydroxypropionic acid (3HP) from acrylic acid was also examined. To enhance the production of 3HP, acrylic acid-assimilating activity was induced by adding 1 mM acrylic acid to the culture medium when the cell density reached an OD600 of 5. Further cultivation of R. erythropolis LG12 with 40 g/l of acrylic acid resulted in the production of 17.5 g/l of 3HP with a molar conversion yield of 44% and productivity of 0.22 g/I/h at 30 degrees after 72 h. PMID:19494695

  20. Facile Fabrication of Gradient Surface Based on (meth)acrylate Copolymer Films

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Yang, H.; Wen, X.-F.; Cheng, J.; Xiong, J.

    2016-08-01

    This paper describes a simple and economic approach for fabrication of surface wettability gradient on poly(butyl acrylate - methyl methacrylate) [P (BA-MMA)] and poly(butyl acrylate - methyl methacrylate - 2-hydroxyethyl methacrylate) [P (BA-MMA-HEMA)] films. The (meth)acrylate copolymer [including P (BA-MMA) and P (BA-MMA-HEMA)] films are hydrolyzed in an aqueous solution of NaOH and the transformation of surface chemical composition is achieved by hydrolysis in NaOH solution. The gradient wetting properties are generated based on different functional groups on the P (BA-MMA) and P (BA-MMA-HEMA) films. The effects of both the surface chemical and surface topography on wetting of the (meth)acrylate copolymer film are discussed. Surface chemical composition along the materials length is determined by XPS, and surface topography properties of the obtained gradient surfaces are analyzed by FESEM and AFM. Water contact angle system (WCAs) results show that the P (BA-MMA-HEMA) films provide a larger slope of the gradient wetting than P (BA-MMA). Moreover, this work demonstrates that the gradient concentration of chemical composition on the poly(meth) acrylate films is owing to the hydrolysis processes of ester group, and the hydrolysis reactions that have negligible influence on the surface morphology of the poly(meth) acrylate films coated on the glass slide. The gradient wettability surfaces may find broad applications in the field of polymer coating due to the compatibility of (meth) acrylate polymer.

  1. Antimicrobial activity of a quaternary ammonium methacryloxy silicate-containing acrylic resin: a randomised clinical trial

    PubMed Central

    Liu, Si-ying; Tonggu, Lige; Niu, Li-na; Gong, Shi-qiang; Fan, Bing; Wang, Liguo; Zhao, Ji-hong; Huang, Cui; Pashley, David H.; Tay, Franklin R.

    2016-01-01

    Quaternary ammonium methacryloxy silicate (QAMS)-containing acrylic resin demonstrated contact-killing antimicrobial ability in vitro after three months of water storage. The objective of the present double-blind randomised clinical trial was to determine the in vivo antimicrobial efficacy of QAMS-containing orthodontic acrylic by using custom-made removable retainers that were worn intraorally by 32 human subjects to create 48-hour multi-species plaque biofilms, using a split-mouth study design. Two control QAMS-free acrylic disks were inserted into the wells on one side of an orthodontic retainer, and two experimental QAMS-containing acrylic disks were inserted into the wells on the other side of the same retainer. After 48 hours, the disks were retrieved and examined for microbial vitality using confocal laser scanning microscopy. No harm to the oral mucosa or systemic health occurred. In the absence of carry-across effect and allocation bias (disks inserted in the left or right side of retainer), significant difference was identified between the percentage kill in the biovolume of QAMS-free control disks (3.73 ± 2.11%) and QAMS-containing experimental disks (33.94 ± 23.88%) retrieved from the subjects (P ≤ 0.001). The results validated that the QAMS-containing acrylic exhibits favourable antimicrobial activity against plaque biofilms in vivo. The QAMS-containing acrylic may also be used for fabricating removable acrylic dentures. PMID:26903314

  2. Chain Transfer of Vegetable Oil Macromonomers in Acrylic Solution Copolymerization

    SciTech Connect

    Black, Micah; Messman, Jamie M; Rawlins, James

    2011-01-01

    Use of vegetable oil macromonomers (VOMMs) as comonomers in emulsion polymerization enables good film coalescence without the addition of solvents that constitute volatile organic compounds (VOCs). VOMMs are derived from renewable resources and offer the potential of post-application crosslinking via auto-oxidation. However, chain transfer reactions of VOMMs with initiator and/or polymer radicals during emulsion polymerization reduce the amount of allylic hydrogen atoms available for primary auto-oxidation during drying. Vegetable oils and derivatives were reacted in combination with butyl acrylate and methyl methacrylate via solution polymerization. The copolymerization was monitored using in situ infrared spectroscopy to determine the extent of chain transfer. 1H NMR spectroscopy was used to determine the loci of chain transfer and the molecular weight characteristics of the polymers were characterized by SEC. Solution polymerization was utilized to minimize temperature fluctuations and maintain polymer solubility during the initial characterization.

  3. Radiation grafting studies of acrylic acid onto cellulose triacetate membranes

    NASA Astrophysics Data System (ADS)

    Mazzei, R. O.; Smolko, E.; Torres, A.; Tadey, D.; Rocco, C.; Gizzi, L.; Strangis, S.

    2002-05-01

    Polymer surface modifications were obtained by the application of radiation treatments, etching and grafting of acrylic acid monomers on different membranes of cellulose triacetate materials. Cellulose triacetate foils from pellet dissolution and commercial cellulose triacetate solid state nuclear track detector membranes were assayed. Irradiation with fission fragments from Cf-252 source to obtain a porous structure, 25 MeV proton beam and Co-60 γ-source to produce peroxides were employed in the experiments. The present work gives the grafting yield of AAc monomer onto CTA membranes as a function of diverse variables including irradiation parameters ( γ-dose, Cf-252 ff irradiation time, proton fluency and electronic energy loss (d E/d x) e), structural parameters (pore diameter and pore density, etching time and etching temperature) and grafting parameters (monomer and Mohr salt concentration, grafting time and grafting temperature).

  4. Strain-controlled fatigue of acrylic bone cement.

    PubMed

    Carter, D R; Gates, E I; Harris, W H

    1982-09-01

    Monotonic tensile tests and tension-compression fatigue tests were conducted of wet acrylic bone cement specimens at 37 degrees C. All testing was conducted in strain control at a strain rate of 0.02/s. Weibull analysis of the tensile tests indicated that monotonic fracture was governed more strongly by strain than stress. The number of cycles to fatigue failure was also more strongly controlled by strain amplitude than stress amplitude. Specimen porosity distribution played a major role in determining the tensile and fatigue strengths. The degree of data scatter suggests that Weibull analysis of fatigue data may be useful in developing design criteria for the surgical use of bone cement. PMID:7130218

  5. Flexural Strength of Cold and Heat Cure Acrylic Resins Reinforced with Different Materials

    PubMed Central

    Heidari, Bijan; Firouz, Farnaz; Izadi, Alireza; Ahmadvand, Shahbaz

    2015-01-01

    Objectives: Heat-polymerized acrylic resin has been the most commonly used denture base material for over 60 years. However, the mechanical strength of acrylic resin is not adequate for long-term clinical performance of dentures. Consequently, fracture is a common clinical occurrence, which often develops in the midline of the denture base. This study aimed to evaluate the efficacy of cold-cure and heat-cure acrylic resins, reinforced with glass fibers, polyethylene fibers, and metal wire for denture base repair. Materials and Methods: Ninety specimens were prepared and allocated to nine groups. Ten specimens were considered as controls, and 80 were divided into 8 experimental groups. In the experimental groups, the specimens were sectioned into two halves from the middle, and were then divided into two main groups: one group was repaired with heat cure acrylic resin, and the other with cold cure acrylic resin. Each group was divided into 4 subgroups: unreinforced, reinforced with glass fibers, polyethylene fibers, and metal wire. All specimens were subjected to a 3-point bending test, and the flexural strength was calculated. Results: The group repaired with heat cure acrylic resin and reinforced with glass fiber showed the highest flexural strength; however, the group repaired with cold cure acrylic resin and reinforced with polyethylene fibers had the lowest flexural strength. There was no significant difference between the groups repaired with heat cure and cold cure acrylic resins without reinforcement. Conclusion: Repairing denture base with heat cure acrylic resin, reinforced with glass fibers increases the flexural strength of denture base. PMID:26877726

  6. Mutagenicity assessment of acrylate and methacrylate compounds and implications for regulatory toxicology requirements.

    PubMed

    Johannsen, F R; Vogt, Barbara; Waite, Maureen; Deskin, Randy

    2008-04-01

    Esters of acrylic acid and methacrylic acid, more commonly known as acrylates and methacrylates, respectively, are key raw materials in the coatings and printing industry, with several of its chemical class used in food packaging. The results of over 200 short-term in vitro and in vivo mutagenicity studies available in the open literature have been evaluated. Despite differences in acrylate or methacrylate functionality or in the number of functional groups, a consistent pattern of test response was seen in a typical regulatory battery of mutagenicity tests. No evidence of point mutations was observed when acrylic acid or over 60 acrylates and methacrylates were investigated in Salmonella bacterial tests or in hprt mutation tests mammalian cells, and no evidence of a mutagenic effect was seen when tested in whole animal clastogenicity and/or aneuploidy (chromosomal aberration/micronucleus) studies. Consistent with the in vivo testing results, acrylic acid exhibited no evidence of carcinogenicity in chronic rodent cancer bioassays. In contrast, acrylic acid and the entire acrylate and methacrylate chemical class produced a consistently positive response when tested in the mouse lymphoma assay and/or other in vitro mammalian cell assays designed to detect clastogenicity. The biological relevance of this in vitro response is questioned based on the non-concordance of in vitro results with those of in vivo studies addressing the same mutagenic endpoint (clastogenicity). Thus, in short-term mutagenicity tests, the acrylates and methacrylates behave as a single chemical category, and genotoxicity behavior of a similar chemical can be predicted with confidence by inclusion within this chemical class, thus avoiding unnecessary testing. PMID:18346829

  7. Drilling fluids containing amps, acrylic acid, itaconic acid polymer

    SciTech Connect

    Bardoliwalla, D.F.

    1987-10-13

    This patent describes an aqueous drilling fluid having present in an amount sufficient to reduce fluid loss of the drilling fluid, at least one polymer of (1) from about 5% to about 50% by weight of 2-acrylamido-2-methylpropane sulfonic acid and (2) from about 95% to about 50% by weight of a second component, there being from 100% to about 80% by weight of acrylic acid and from 0% by weight to about 20% by weight of itaconic acid in the second component. The polymer has a weight average molecular weight of between about 50,000 to about 1,000,000 being in its free acid or partially or completely neutralized form and being at least water dispersible. A method is described of drilling a well into a subterranean formation in which an aqueous drilling fluid is circulated into the well. The step of circulating the drilling fluid contains in an amount sufficient to reduce fluid loss of the drilling fluid, at least one polymer of (1) from about 5% to about 50% by weight of 2-acrylamido-2-methylpropane sulfonic acid and (2) from about 95% to about 50% by weight of a second component. There is from 100% to about 80% by weight of acrylic acid and from 0% by weight to about 20% by weight of itaconic acid in the second component. The polymer has weight average molecular weight of between about 50,000 to about 1,000,000 in its free acid or partially or completely neutralized form and is at least water dispersible.

  8. Amino-functionalized (meth)acryl polymers by use of a solvent-polarity sensitive protecting group (Br-t-BOC)

    PubMed Central

    Tabatabai, Monir; Herrmann, Markus

    2016-01-01

    Summary We describe the synthesis of bromo-tert-butyloxycarbonyl (Br-t-BOC)-amino-protected monomers 2-((1-bromo-2-methylpropan-2-yl)oxycarbonylamino)ethyl (meth)acrylate 3a,b. For this purpose, 2-isocyanatoethyl (meth)acrylate 1a,b was reacted with 1-bromo-2-methylpropan-2-ol (2a). The free radical polymerization of (Br-t-BOC)-aminoethyl (meth)acrylates 3a,b yielded poly((Br-t-BOC)-aminoethyl (meth)acrylate) 6a,b bearing protected amino side groups. The subsequent solvolysis of the Br-t-BOC function led to the new polymers poly(2-aminoethyl (meth)acrylate) 8a,b with protonated free amino groups. The monomers and the resulting polymers were thoroughly characterized by 1H NMR, IR, GPC and DSC methods. The kinetics of the deprotection step was followed by 1H NMR spectroscopy. The solvent polarity and neighboring group effects on the kinetics of deprotection are discussed. PMID:26977183

  9. Amino-functionalized (meth)acryl polymers by use of a solvent-polarity sensitive protecting group (Br-t-BOC).

    PubMed

    Ritter, Helmut; Tabatabai, Monir; Herrmann, Markus

    2016-01-01

    We describe the synthesis of bromo-tert-butyloxycarbonyl (Br-t-BOC)-amino-protected monomers 2-((1-bromo-2-methylpropan-2-yl)oxycarbonylamino)ethyl (meth)acrylate 3a,b. For this purpose, 2-isocyanatoethyl (meth)acrylate 1a,b was reacted with 1-bromo-2-methylpropan-2-ol (2a). The free radical polymerization of (Br-t-BOC)-aminoethyl (meth)acrylates 3a,b yielded poly((Br-t-BOC)-aminoethyl (meth)acrylate) 6a,b bearing protected amino side groups. The subsequent solvolysis of the Br-t-BOC function led to the new polymers poly(2-aminoethyl (meth)acrylate) 8a,b with protonated free amino groups. The monomers and the resulting polymers were thoroughly characterized by (1)H NMR, IR, GPC and DSC methods. The kinetics of the deprotection step was followed by (1)H NMR spectroscopy. The solvent polarity and neighboring group effects on the kinetics of deprotection are discussed. PMID:26977183

  10. Attachment of Candida albicans to denture base acrylic resin processed by three different methods.

    PubMed

    Young, Beth; Jose, Anto; Cameron, Donald; McCord, Fraser; Murray, Colin; Bagg, Jeremy; Ramage, Gordon

    2009-01-01

    Denture stomatitis is a debilitating disease associated with the presence of adherent Candida albicans. This study compared the attachment capacity of C. albicans to three different acrylic resin materials (self-curing [SC], conventional pressure-packed [CPP], and injection-molded [IM]) to determine whether the physical properties of the materials influenced candidal attachment. No significant differences in attachment between the isolates were observed for each acrylic resin. However, a comparison of the mean of all isolates showed significantly less attachment to SC than to CPP (P < .05). These data indicate that choice of denture acrylic resin material may influence the capacity for developing denture stomatitis. PMID:20095199

  11. Structural study of photodegraded acrylic-coated lime wood using Fourier transform infrared and two-dimensional infrared correlation spectroscopy.

    PubMed

    Popescu, Carmen-Mihaela; Simionescu, Bogdan C

    2013-06-01

    The weathering of acrylic films and acrylic-coated lime wood (Tillia cordata Mill.) were examined using Fourier transform infrared (FT-IR) and two-dimensional infrared correlation spectroscopy. The obtained results showed chemical changes induced by exposure to weathering conditions, in both films and coated wood. The observed spectral changes of the acrylic films refer to the absorption band assigned to the C-O stretching, which progressively decreases with increasing exposure time. In the spectra of treated wood samples the main signal indicating the advance of oxidation during the photodegradation exposure is the gradual increase and broadening of the band in the carbonyl region. This is due to the formation of the non-hydrogen bonded aliphatic carboxylic acids and γ-lactone structures in the acrylic resin and of the nonconjugated ketones, carboxyl groups, and lactones in wood. As a consequence, the increase of the 1734 cm(-1) band is due to the degradation of lignin from wood surface. These observations are also supported by the decreased intensities of the bands at 1598 and 1505 cm(-1), assigned to C=C of aromatic skeletal (lignin). The relative intensity of the characteristic aromatic lignin band at 1505 cm(-1) decreases up to 25% of its original value after weathering, being less than half of the value obtained for uncoated wood. Two-dimensional infrared (2D IR) correlation spectroscopy was used to identify the sequence of the modifications of the different stretching vibrations bands under the weathering conditions, the method allowing the prediction of the order of degradation reactions. The acrylic resin degradation starts with the formation of radicals by abstraction of the tertiary hydrogen atoms of the methyl acrylate units and the α-CH3 groups from the ethyl methacrylate units. The subsequent decomposition and oxidation led to the formation of alcohol groups, hydroperoxides, ketones, and/or carboxylic acid groups. The 2D IR correlation spectra of

  12. Novel (meth)acrylate monomers for ultrarapid polymerization and enhanced polymer properties

    SciTech Connect

    Beckel, E. R.; Berchtold, K. A.; Nie, J.; Lu, H.; Stansbury, J. W.; Bowman, C. N.

    2002-01-01

    Ultraviolet light is known to be one of the most efficient methods to initiatc polymeric reactions in the presence of a photonitiator. Photopolymerizations are advantageous because the chemistry of the materials can be tailored to design liquid monomers for ultrarapid polymerization into a solid polymer material. One way to achieve rapid photopolymerizations is to utilize multifunctional (meth)acrylate monomers. which form highly crosslinked polymers; however, these monomers typically do not achieve complete functional group conversion. Recently, Decker et al. developed novel monovinyl acrylate monomers that display polyriicrization kinetics that rival those of multifunctional acrylate monomers. These novel acrylate monomers incorporate secondary functionalities and end groups such as carbonates, carbamates, cyclic carbonates and oxazolidone which promote the increased polymerization kinetics of these monomers. In addition to thc polynierization kinetics, these novel monovinyl monomers form crosslinked polymers, which are characterized by having high strength and high flexibility. Unfortunately, the exact mechanism or mechanisms responsible for the polymerization kinetics and crosslinking are not well understood.

  13. Removal of methyl acrylate by ceramic-packed biotrickling filter and their response to bacterial community.

    PubMed

    Wu, Hao; Yin, Zhenhao; Quan, Yue; Fang, Yingyu; Yin, Chengri

    2016-06-01

    Methyl acrylate is a widely used raw chemical materials and it is toxic in humans. In order to treat the methyl acrylate waste gas, a 3-layer BTF packed with ceramic particles and immobilized with activated sludge was set up. The BTF exhibited excellent removal efficiency that no methyl acrylate could be detected when EBRT was larger than 266s and inlet concentration was lower than 0.19g/m(3). The 1st layer performed the best at fixed inlet concentration of 0.42g/m(3). PCR combined with DGGE was performed to detect the differences in different layers of the BTF. Phylum Proteobacteria (e.g. α-, β-, γ-, δ-) was predominantly represented in the bacterial community, followed by Actinobacteria and Firmicutes. Desulfovibrio gigas, Variovorax paradoxus, Dokdonella koreensis, Pseudoxanthomonas suwonensis, Azorhizobium caulinodans, Hyphomicrobium denitrificans, Hyphomicrobium sp. and Comamonas testosteroni formed the bacteria community to treat methyl acrylate waste gas in the BTF. PMID:26970927

  14. Wear of combinations of acrylic resin and porcelain, on an abrasion testing machine.

    PubMed

    Harrison, A

    1978-04-01

    Wear tests of various combinations of acrylic resin and porcelain were made using a machine which was designed to test materials under conditions similar to those of masticatory function by simulating the loads, sliding distances, and contact times encountered in the human masticatory cycle. The results showed that the amount of wear of the two materials worn in combination depended on the nature of the surrounding medium and on the surface roughness of the opposing material. Acrylic resin showed good wear resistance provided no third party abrasive or opposing hard, rough surface was present. When a mild abrasive was incorporated in the system, the acrylic resin vs acrylic resin combination wore almost seven times more than porcelain vs porcelain. Clinical experience would suggest that this is a reasonably sound order of wear. PMID:213546

  15. Synthesis and self-assembly of poly(3-hexylthiophene)-block-poly(acrylic acid)

    SciTech Connect

    Li, Zicheng; Ono, Robert J.; Wu, Zong-Quan; Bielawski, Christopher W.

    2011-01-01

    A modular and convenient synthesis of ethynyl end functionalized poly(3-hexylthiophene) in high purity is reported; this material facilitated access to poly(3-hexylthiophene)-block-poly(acrylic acid) which self-assembled into hierarchical structures.

  16. Biobased composites from thermoplastic polyurethane elastomer and cross-linked acrylated-epoxidized soybean oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean oil is an important sustainable material. Crosslinked acrylated epoxidized soybean oil (AESO) is brittle without flexibility and the incorporation of thermoplastic polyurethane improves its toughness for industrial applications. The hydrophilic functional groups from both oil and polyurethan...

  17. Synthesis and characterization of amylose grafted poly(acrylic acid) and its application in ammonia adsorption.

    PubMed

    Chen, Qing; Yu, Haojie; Wang, Li; Abdin, Zain-Ul; Yang, Xinpeng; Wang, Junhua; Zhou, Weidong; Zhang, Hongtao; Chen, Xiao

    2016-11-20

    Amylose grafted poly(acrylic acid) (Am-g-PAA) was synthesized by graft copolymerization of amylose with acrylic acid. The structure of Am-g-PAA was confirmed by (1)H NMR and FT-IR spectra. The morphology, crystallinity and thermal properties of amylose and Am-g-PAA were investigated by SEM, XRD and TGA, respectively. The highest degree of substitution (DS) of carboxyl group was 1.96 which was obtained after reacted for 1h at 60°C. Acrylic acid to anhydroglucose mole ratio for DS was 19.81. It was found that a large number of carboxyl groups were grafted on the backbone of amylose. It was also found that ammonia adsorption capacity of amylose increased by grafting poly(acrylic acid) on the backbone of amylose. PMID:27561514

  18. Clarification of the blood compatibility mechanism by controlling the water structure at the blood-poly(meth)acrylate interface.

    PubMed

    Tanaka, Masaru; Mochizuki, Akira

    2010-01-01

    In previous studies, we reported that poly(2-methoxyethyl acrylate) (PMEA) exhibited excellent blood compatibility, although it has a simple chemical structure. Since then, we have been investigating the reasons for its blood compatibility. In this short review, we consider the reasons for this compatibility by comparing the structure of water in hydrated PMEA to the water structure of poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(meth)acrylate analogs as reference polymers. The hydrated water in PMEA could be classified into three types; free water (or freezing water), freezing-bound water (or intermediate water), and non-freezing water (or non-freezing-bound water). We found that hydrated PMEA possessed a unique water structure, observed as cold crystallization of water in differential scanning calorimetry (DSC). Cold crystallization is interpreted as ice formation at low temperature, an attribute of freezing-bound water in PMEA. The cold crystallization peak was observed for hydrated poly(ethylene glycol) (PEG), poly(vinyl methyl ether) (PVME), polyvinylpyrrolidone (PVP), poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), poly(tetrahydrofurfuryl acrylate) (PTHFA), and newly synthesized poly(2-(2-ethoxyethoxy)ethyl acrylate), as well as various proteins and polysaccharides, which are well-known biocompatible polymers. On the other hand, cold crystallization of water was not observed in hydrated PHEMA and PMEA analogous polymers, which do not show excellent blood compatibility. Based on these findings, we hypothesized that freezing-bound water, which prevents the biocomponents from directly contacting the polymer surface or non-freezing water on the polymer surface, plays an important role in the excellent blood compatibility of PMEA. PMID:20699056

  19. Structure and properties of binary polystyrene-epoxy acrylate oligomer mixtures irradiated by electron beams

    SciTech Connect

    Lomonosova, N.V.

    1995-03-01

    The change in the structure of oriented polymer-oligomer systems based on polystyrene (PS) with M > 10{sup 6} and epoxy acrylate oligomers (aliphatic and aromatic) under irradiation by accelerated electrons was studied using birefringence, isometric heating, IR dichroism, and thermooptical analysis. Mechanical properties of these systems were investigated. It was found that, by adding aliphatic epoxy acrylate to PS and further irradiating this mixture, one can obtain both isotropic and oriented composites with higher strengths, elasticity moduli, and glass transition temperatures.

  20. Silver hollow optical fibers with acrylic silicone resin coating as buffer layer for sturdy structure

    NASA Astrophysics Data System (ADS)

    Iwai, Katsumasa; Takaku, Hiroyuki; Miyagi, Mitsunobu; Shi, Yi-Wei; Zhu, Xiao-Song; Matsuura, Yuji

    2016-03-01

    For sturdy silver hollow optical fibers, acrylic silicone resin is newly used as a buffer layer between an inner silver layer and a silica capillary. This acrylic silicone resin film prevents the glass surface from chemical and mechanical micro damages during silver plating process, which deteriorate mechanical strength of the hollow fibers. In addition, it keeps high adhesion of the silver layer with the glass surface. We discuss improvement of mechanical strength of the hollow glass fibers without deterioration of optical properties.

  1. Testing of gloves for permeability to UV-curable acrylate coatings

    SciTech Connect

    Huggins, R.; Levy, N.; Pruitt, P.M.

    1987-07-01

    The handling of UV-curable acrylate formulations used in the coating of optical fiber requires protective measures to prevent contact dermatitis and/or allergic dermatitis. To characterize the permeability of various glove materials to a UV-curable acrylate coating, a study was undertaken using a modification of a standard ASTM permeability test, which demonstrated that nitrile rubber gloves provided the best protection of those glove materials tested.

  2. Mucoadhesive acrylated block copolymers micelles for the delivery of hydrophobic drugs.

    PubMed

    Eshel-Green, Tal; Bianco-Peled, Havazelet

    2016-03-01

    Blockpolymer micelles having acrylated end groups were fabricated for the development of mucoadhesive drug loaded vehicle. The critical micelle concentration (CMC) of Pluronic(®) F127 modified with acrylate end groups (F127DA) was found to be similar to that of the unmodified Pluronic(®) F127 (F127). Small angle X-ray scattering verified existence of micelles with an inner core of 4.9±0.2 and 5.5±0.3 for F127 and F127DA respectively. Indomethacin, a hydrophobic drug, was incorporated into the micelles using the thin-film hydration method. In vitro drug release assay demonstrated that the micelles sustained the release of the drug in comparison with free drug in solution. Several methods were used for mucoadhesion evaluation. Viscosity profiling was performed by shear rate sweep experiment of hydrated commercial mucin, F127 or F127DA, and combination of both mucin and a copolymer. Elevated viscosity was achieved for acrylated micelles with mucin compared to mixtures of non-acrylated micelles with mucin. The mucoadhesivity of the acrylated micelles was further characterized using nuclear magnetic resonance (NMR); data affirmed the Michael type addition reaction occurred between acrylates on the micelles corona and thiols present in the mucin. SAXS scattering data further showed a modification in the scattering of F127DA micelles with the addition of pig gastric mucin. Cryo-transmission electron microscopy (cryo-TEM) and dynamic light scattering (DLS) data detected increase in the aggregates size while using acrylated micelles enhance mucoadhesion. Thus acrylated F127DA micelles were found to be mucoadhesive, and a suitable and preferred candidate for micellar drug delivery to mucosal surfaces. PMID:26700232

  3. Color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for non metal clasp denture

    PubMed Central

    Jang, Dae-Eun; Lee, Ji-Young; Jang, Hyun-Seon; Lee, Jang-Jae

    2015-01-01

    PURPOSE The aim of this study was to compare the color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for the non-metal clasp dentures to those of thermoplastic polyamide and conventional heat-polymerized denture base resins. MATERIALS AND METHODS Three types of denture base resin, which are conventional heat-polymerized acrylic resin (Paladent 20), thermoplastic polyamide resin (Bio Tone), thermoplastic acrylic resin (Acrytone) were used as materials for this study. One hundred five specimens were fabricated. For the color stability test, specimens were immersed in the coffee and green tee for 1 and 8 weeks. Color change was measured by spectrometer. Water sorption was tested after 1 and 8 weeks immersion in the water. For the test of cytotoxicity, cell viability assay was measured and cell attachment was analyzed by FE-SEM. RESULTS All types of denture base resin showed color changes after 1 and 8 weeks immersion. However, there was no significant difference between denture base resins. All specimens showed significant color changes in the coffee than green tee. In water sorption test, thermoplastic acrylic resin showed lower values than conventional heat-polymerized acrylic resin and thermoplastic polyamide resin. Three types of denture base showed low cytotoxicity in cell viability assay. Thermoplastic acrylic resin showed the similar cell attachment but more stable attachment than conventional heat-polymerized acrylic resin. CONCLUSION Thermoplastic acrylic resin for the non-metal clasp denture showed acceptable color stability, water sorption and cytotoxicity. To verify the long stability in the mouth, additional in vitro studies are needed. PMID:26330974

  4. Continuous process of preparation of n-butyl(meth)acrylate by esterification of (meth)acrylic acid by butanol on thermostable sulfo-cation exchanger

    SciTech Connect

    Zheleznaya, L.L.; Karakhanov, R.A.; Lunin, A.F.; Magadov, R.S.; Meshcheryakov, S.V.; Mkrtychan, V.R.; Fomin, V.A.

    1987-11-10

    The authors propose an effective thermostable sulfo-cation exchanger based on polymers with a system of conjugated bonds, sulfopolyphenylene ketone (SPP) differing from the known cation exchangers by the high thermostability (up to 250/sup 0/C), and also having the effect of the stabilization of the double bond in unsaturated monomers. The combination of inhibiting and cation exchange properties makes it also possible to use these sulfo-cation exchangers in the processes of esterification of (meth)acrylic acids by alcohols without addition of special inhibitors. The SPP catalyst was tested in esterification processes of acrylic an methacrylic acid by butanol at a pilot plant.

  5. Radiopurity measurement of acrylic for the DEAP-3600 dark matter experiment

    NASA Astrophysics Data System (ADS)

    Nantais, Corina Michelle

    2014-05-01

    The liquid argon target of the DEAP-3600 dark matter detector is contained by an extremely radiopure acrylic vessel. Alpha decays from the inner surface of the acrylic vessel are a source of background. If a fraction of the alpha energy is observed, or if the recoiling nucleus from the alpha decay is observed, the event will not be separated from a dark matter candidate event. In addition to the low level of inherent contamination from uranium and thorium, the Pb-210 from Rn-222 diffusion during manufacturing must be measured. The limit for the DEAP-3600 acrylic vessel is 1.1 x 10-20 g/g Pb-210. By vaporizing a large quantity of acrylic and counting the concentrated residue with an ultralow background HPGe well detector and a low background alpha spectrometer, the bulk acrylic was found to have an upper limit of 10 -19 g/g Pb-210. The design, installation, commissioning, operation, and analysis for various aspects of the acrylic assay are described.

  6. MM and QM: conformational and vibrational spectra analysis of 2-hydroxyethyl acrylate.

    PubMed

    Belaidi, O; Adjim, M; Bouchaour, T; Maschke, U

    2015-02-25

    2-Hydroxyethyl acrylate is generally used with other acrylic and methacrylic products in order to get the desired characteristics of the final product. In this work we are about to make an assignment of experimental infrared bands with the help of a theoretical quantum chemistry calculations. The exact knowledge of some bands which are not characteristics of acrylic materials will enable us to make a quick analysis with available techniques of low costs for mixtures of polymers based on acrylate and methacrylate molecules. In the experimental part, the infrared spectrum of 2-hydroxyethyl acrylate is obtained by using a FTIR Perkin Elmer model 2000. In the computational part and as first step, the theoretical calculations are performed by the semi-empirical AM1 method for excluding similar structures of 2-hydroxyethyl acrylate molecule by a meticulous conformational analysis. As a second step the obtained structures are optimized using DFT. The simulated frequencies are then scaled and a tentative assignment is made based on band intensities and PED percentages. The theoretical calculations predict the existence of thirteen conformations two of them represent the majority of experimental bands in the infrared spectrum. Two neighbor experimental bands located at 1301 and 1207 cm(-1) maybe used as characteristic bands to locate and distinguish the existence of one or both conformations. PMID:25194321

  7. Effect of microwave treatments on dimensional accuracy of maxillary acrylic resin denture base.

    PubMed

    Pavan, Sabrina; Arioli Filho, João Neudenir; Dos Santos, Paulo Henrique; Mollo, Francisco de Assis

    2005-01-01

    Microwave energy has been used as an alternative method for disinfection and sterilization of dental prostheses. This study evaluated the influence of microwave treatment on dimensional accuracy along the posterior palatal border of maxillary acrylic resin denture bases processed by water-bath curing. Thirty maxillary acrylic bases (3-mm-thick) were made on cast models with Clássico acrylic resin using routine technique. After polymerization and cooling, the sets were deflasked and the bases were stored in water for 30 days. Thereafter, the specimens were assigned to 3 groups (n=10), as follows: group I (control) was not submitted to any disinfection cycle; group II was submitted to microwave disinfection for 3 min at 500 W; and in group III microwaving was done for 10 min at 604 W. The acrylic bases were fixed on their respective casts with instant adhesive (Super Bonder) and the base/cast sets were sectioned transversally in the posterior palatal zone. The existence of gaps between the casts and acrylic bases was assessed using a profile projector at 5 points. No statistically significant differences were observed between the control group and group II. However, group III differed statistically from the others (p<0.05). Treatment in microwave oven at 604 W for 10 min produced the greatest discrepancies in the adaptation of maxillary acrylic resin denture bases to the stone casts. PMID:16475605

  8. MM and QM: Conformational and vibrational spectra analysis of 2-hydroxyethyl acrylate

    NASA Astrophysics Data System (ADS)

    Belaidi, O.; Adjim, M.; Bouchaour, T.; Maschke, U.

    2015-02-01

    2-Hydroxyethyl acrylate is generally used with other acrylic and methacrylic products in order to get the desired characteristics of the final product. In this work we are about to make an assignment of experimental infrared bands with the help of a theoretical quantum chemistry calculations. The exact knowledge of some bands which are not characteristics of acrylic materials will enable us to make a quick analysis with available techniques of low costs for mixtures of polymers based on acrylate and methacrylate molecules. In the experimental part, the infrared spectrum of 2-hydroxyethyl acrylate is obtained by using a FTIR Perkin Elmer model 2000. In the computational part and as first step, the theoretical calculations are performed by the semi-empirical AM1 method for excluding similar structures of 2-hydroxyethyl acrylate molecule by a meticulous conformational analysis. As a second step the obtained structures are optimized using DFT. The simulated frequencies are then scaled and a tentative assignment is made based on band intensities and PED percentages. The theoretical calculations predict the existence of thirteen conformations two of them represent the majority of experimental bands in the infrared spectrum. Two neighbor experimental bands located at 1301 and 1207 cm-1 maybe used as characteristic bands to locate and distinguish the existence of one or both conformations.

  9. Radiation-induced grafting of acrylic acid onto polypropylene film and its biodegradability

    NASA Astrophysics Data System (ADS)

    Mandal, Dev K.; Bhunia, Haripada; Bajpai, Pramod K.; Chaudhari, C. V.; Dubey, K. A.; Varshney, L.

    2016-06-01

    Polypropylene based commodity polyolefins are widely used in packaging, manufacturing, electrical, pharmaceutical and other applications. The aim of the present work is to study the effect of grafting of acrylic acid on the biodegradability of acrylic acid grafted polypropylene. The effect of different conditions showed that grafting percentage increased with increase in monomer concentration, radiation dose and inhibitor concentration but decreased with increase in radiation dose rate. The maximum grafting of 159.4% could be achieved at optimum conditions. The structure of grafted polypropylene films at different degree of grafting was characterized by EDS, FTIR, TGA, DSC, SEM and XRD. EDS studies showed that the increase in acrylic acid grafting percentage increased the hydrophilicity of the grafted films. FTIR studies indicated the presence of acrylic acid on the surface of polypropylene film. TGA studies revealed that thermal stability decreased with increase in grafting percentage. DSC studies showed that melting temperature and crystallinity of the grafted polypropylene films lower than polypropylene film. SEM studies indicated that increase in acrylic acid grafting percentage increased the wrinkles in the grafted films. The maximum biodegradability could be achieved to 6.85% for 90.5% grafting. This suggested that microorganisms present in the compost could biodegrade acrylic acid grafted polypropylene.

  10. Starch graft poly(methyl acrylate) loose-fill foam: preparation, properties and degradation.

    PubMed

    Chen, L; Gordon, S H; Imam, S H

    2004-01-01

    Starch graft poly(methyl acrylate) (S-g-PMA) was prepared by ceric ion initiation of methyl acrylate in an aqueous corn starch slurry (prime starch) which maximized the accessibility of the starch for graft polymerization. A new ceric ion reaction sequence was established as starch-initiator-methyl acrylate followed by addition of a small amount of ceric ion solution when the graft polymerization was almost complete to quench the reaction. As a result of this improved procedure, no unreacted methyl acrylate monomer remained, and thus, essentially no ungrafted poly(methyl acrylate) homopolymer was formed in the final grafted product. Quantities of the high purity S-g-PMA so prepared in pilot scale were converted to resin pellets and loose-fill foam by single screw and twin screw extrusion. The use of prime starch significantly improved the physical properties of the final loose-fill foam, in comparison to foam produced from regular dry corn starch. The S-g-PMA loose-fill foam had compressive strength and resiliency comparable to expanded polystyrene but higher bulk density. The S-g-PMA loose-fill foam also had better moisture and water resistance than other competitive starch-based materials. Studies indicated that the starch portion in S-g-PMA loose-fill foam biodegraded rapidly, whereas poly(methyl acrylate) remained relatively stable under natural environmental conditions. PMID:14715032

  11. Hybrid resist systems based on α-substituted acrylate copolymers

    NASA Astrophysics Data System (ADS)

    Ito, Hiroshi; Sundberg, Linda K.; Bozano, Luisa; Lofano, Elizabeth M.; Yamanaka, Kazuhiro; Terui, Yoshiharu; Fujiwara, Masaki

    2009-03-01

    Classical electron-beam resists such as poly(methyl methacrylate) (PMMA) and Nippon Zeon's ZEP function as high resolution and low roughness positive resists on the basis of radiation induced main chain scission to reduce the molecular weight while chemical amplification resists utilized in device manufacturing function on the basis of acidcatalyzed deprotection to change the polarity. In an attempt to increase the resolution and reduce the line roughness of chemical amplification resists, we prepared copolymers that undergo radiation induced main chain scission and acidcatalyzed deprotection. In another word, we wanted to increase the sensitivity of the PMMA resist by incorporating the acid-catalyzed deprotection mechanism in polymers that undergo main chain scission, maintaining the high resolution and low roughness of PMMA. To synthesize such hybrid resist polymers, we selected α-substituted acrylates and α- substituted styrenes. The former included methyl methacrylate (MMA), t-butyl methacrylate (TBMA), methyl α- fluoroacrylate (MFA), t-butyl α-fluoroacrylate (TBFA), and t-butyl α-trifluoromethylacrylate (TBTFMA) and the latter α-methylstyrene (αMEST), α-methyleneindane (αMEIN), and α-methylenetetralin (αMETL). The α-substituted tbutyl acrylic esters were copolymerized with the methyl esters and also with α-substituted styrenic monomers using 2, 2'-azobis(isobutyronitrile) (AIBN). Hybrid resists were formulated by adding a photochemical acid generator and a base quencher to the copolymers and developers were selected by studying the dissolution behavior of unexposed and 254 nm exposed resist films using a quartz crystal microbalance (QCM). In addition to the difference in the imaging mechanism, PMMA and ZEP differ from the chemical amplification resists in developers; organic solvent vs. aqueous base. We were interested in looking also into the influence of the developer on the lithographic performance. Contrast curves were generated by exposing

  12. Bone Marrow Nails Created by Percutaneous Osteoplasty for Long Bone Fracture: Comparisons Among Acrylic Cement Alone, Acrylic-Cement-Filled Bare Metallic Stent, and Acrylic-Cement-Filled Covered Metallic Stent

    SciTech Connect

    Nakata, Kouhei; Kawai, Nobuyuki; Sato, Morio Cao, Guang; Sahara, Shinya; Sonomura, Tetsuo; Takasaka, Isao; Minamiguchi, Hiroki; Nakai, Motoki

    2011-06-15

    Purpose: This study was designed to compare the strength among bone marrow nails created to treat long bone fractures using interventional procedures. Methods: Twelve resected intact tibiae of healthy swine were used. A circumferential bone fracture was made in nine tibiae and restored with the following created bone marrow nails: acrylic cement alone (ACA) (n = 3), acrylic-cement-filled bare metallic stent (AC-FBMS) (n = 3), and acrylic-cement-filled covered metallic (AC-FCMS) stent (n = 3). The remaining intact tibiae (n = 3) were used as controls. Results: A bone marrow nail was successfully achieved within 30 min in all swine. The maximum injection volume of acrylic cement for creating ACA, AC-FBMS, and AC-FCMS was 1.7 {+-} 0.3, 3.2 {+-} 0.4, and 2.9 {+-} 0.4 mL, respectively. The thickness of bone marrow nail created in the ACA, AC-FBMS, and AC-FCMS groups was 3.6 {+-} 1.0, 10.3 {+-} 0.26, and 9.6 {+-} 0.32 mm, respectively (AC-FBMS group versus AC-FCMS group, p = 0.038), probably because of leakage of acrylic cement surrounding the interstices. The maximum bending power (kilonewton) and bending strength (newton/mm{sup 2}) in the normal long bone, ACA, AC-FBMS, and AC-FCMS groups were: 1.70 {+-} 0.25 and 79.2 {+-} 16.1; 0.21 {+-} 0.11 and 8.8 {+-} 2.8; 0.46 {+-} 0.06 and 18.2 {+-} 1.6; and 0.18 {+-} 0.04 and 7.8 {+-} 2.7, respectively. Conclusions: Although the maximum bending power and bending strength of AC-FBMS were not satisfactory, it was the most robust of the three marrow nails for restoring fractured long bone.

  13. Self-Assembly and Relaxation Behavior of Graphene Containing Acrylic Triblock Copolymer Gels

    NASA Astrophysics Data System (ADS)

    Zabet, Mahla; Hashemnejad, Seyedmeysam; Kundu, Santanu

    2015-03-01

    Investigation of gel mechanical properties as a function of their structure is a significant research interest. This study presents the effect of graphene (or few-layer graphene) on the self-assembly and the relaxation behavior of a thermoreversible gel consists of a physically cross-linked poly (methyl methacrylate)-poly (n-butyl acrylate)-poly (methyl methacrylate) [PMMA-PnBA-PMMA] triblock copolymer in 2-ethyl-1-hexanol, a midblock selective solvent. Graphene was obtained by sonicating exfoliated graphite in 2-ethyl-1-hexanol at various concentrations. Filtration technique and spectrophotometry were utilized to measure the graphene concentration in the dispersions. The dispersed graphene was then incorporated in a series of gels and the effect of graphene on mechanical properties, including the relaxation behavior were studied. Small angle X-ray scattering (SAXS) was used to investigate the microstructure of these gels at room temperature. SAXS data were analyzed to estimate the number of end blocks per junction zone, the average spacing between the junctions, and the change of these properties as a function of graphene concentration. The results indicate that the presence of graphene affects the self-assembly process.

  14. Prosthetic rehabilitation of the gagging patient using acrylic training plates.

    PubMed

    Ali, Rahat; Altaie, Asmaa; Morrow, Leean

    2015-01-01

    Patients with a hyper-responsive gag reflex pose dentists with a challenging problem. The gag reflex of some patients may be so severe that patients (and operating clinician) may favour extraction of any painful, infected teeth as opposed to more lengthy and complicated procedures such as root canal therapy. However, consistently adopting this approach may render the gagging patient completely edentulous. Such patients may then present to the dental surgeon requesting tooth replacement with some form of denture. This in itself can be a challenging task given the difficulties one may experience whilst taking impressions in this cohort of patients. This article will discuss the prosthetic management of the maxillary arch in edentulous patients with a severe gag reflex. There will be particular emphasis on the aetiology and physiology of the gag reflex, impression-taking techniques to allow the construction of an acrylic training plate (as an interim measure), principles of training plate design and construction of the definitive removable denture. Clinical Relevance: Removable training plates can be used as an interim measure to desensitize edentulous gagging patients before providing them with a definitive removable denture. PMID:26062279

  15. Synthesis of acrylates and methacrylates from coal-derived syngas

    SciTech Connect

    Spivey, J.J.; Gogate, M.R.; Jang, B.W.L.

    1995-12-31

    Acrylates and methacrylates are among the most widely used chemical intermediates in the world. One of the key chemicals of this type is methyl methacrylate. Of the 4 billion pounds produced each year, roughly 85% is made using the acetone-cyanohydrin process, which requires handling of large quantities of hydrogen cyanide and produces ammonium sulfate wastes that pose an environmental disposal challenge. The U.S. Department of Energy and Eastman Chemical Company are sharing the cost of research to develop an alternative process for the synthesis of methyl methacrylate from syngas. Research Triangle Institute is focusing on the synthesis and testing of active catalysts for the condensation reactions, and Bechtel is analyzing the costs to determine the competitiveness of several process alternatives. Results thus far show that the catalysts for the condensation of formaldehyde and the propionate are key to selectively producing the desired product, methacrylic acid, with a high yield. These condensation catalysts have both acid and base functions and the strength and distribution of these acid-base sites controls the product selectivity and yield.

  16. Cytocompatible antifungal acrylic resin containing silver nanoparticles for dentures

    PubMed Central

    Acosta-Torres, Laura Susana; Mendieta, Irasema; Nuñez-Anita, Rosa Elvira; Cajero-Juárez, Marcos; Castaño, Víctor M

    2012-01-01

    Background Inhibition of Candida albicans on denture resins could play a significant role in preventing the development of denture stomatitis. The safety of a new dental material with antifungal properties was analyzed in this work. Methods Poly(methyl methacrylate) [PMMA] discs and PMMA-silver nanoparticle discs were formulated, with the commercial acrylic resin, Nature-CrylTM, used as a control. Silver nanoparticles were synthesized and characterized by ultraviolet-visible spectroscopy, dispersive Raman spectroscopy, and transmission electron microscopy. The antifungal effect was assessed using a luminescent microbial cell viability assay. Biocompatibility tests were carried out using NIH-3T3 mouse embryonic fibroblasts and a Jurkat human lymphocyte cell line. Cells were cultured for 24 or 72 hours in the presence or absence of the polymer formulations and analyzed using three different tests, ie, cellular viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation by enzyme-linked immunosorbent assay BrdU, and genomic DNA damage (Comet assay). Finally, the samples were evaluated mechanically, and the polymer-bearing silver nanoparticles were analyzed microscopically to evaluate dispersion of the nanoparticles. Results The results show that PMMA-silver nanoparticle discs significantly reduce adherence of C. albicans and do not affect metabolism or proliferation. They also appear not to cause genotoxic damage to cells. Conclusion The present work has developed a new biocompatible antifungal PMMA denture base material. PMID:22969297

  17. Mechanical properties of single pellets containing acrylic polymers.

    PubMed

    Wang, C C; Zhang, G; Shah, N H; Infeld, M H; Malick, A W; McGinity, J W

    1996-07-01

    Three aqueous-based acrylic latex dispersions, Eudragit L 30 D, NE 30 D, and RS 30 D, were incorporated as granulating binders into a powder blend of microcrystalline cellulose and anhydrous lactose by wet massing. Spheronized pellets were prepared by extrusion-spheronization and the mechanical properties of single pellets, including the tensile strength at break and the Young's modulus were determined from the stress-strain profiles using a Chatillon TCD-200 tension/compression digital test gauge. The influence of particle size and plasticizer on the mechanical properties of pellets containing Eudragit RS 30 D was investigated. All bead formulations deformed by brittle fracture under a diametral compression force. The mechanical strength was found to be influenced by the adhesive strength between the polymers and the powder particles instead of the cohesive strength of each polymer. The Young's modulus and the tensile strength were also significantly influenced by the type and concentration of polymer, the presence of plasticizer, and the particle size of the beads. The results were related to the properties of the polymers and the fracture mechanisms of the beads. Furthermore, the polymer type and the incorporation of plasticizer influenced the susceptibility of the moistened extruded granules to the shearing forces during the spheronization process, which influenced the surface morphological properties of the pellets. PMID:9552348

  18. Interaction of photosensitive surfactant with DNA and poly acrylic acid.

    PubMed

    Zakrevskyy, Yuriy; Cywinski, Piotr; Cywinska, Magdalena; Paasche, Jens; Lomadze, Nino; Reich, Oliver; Löhmannsröben, Hans-Gerd; Santer, Svetlana

    2014-01-28

    In this paper, we investigate interactions and phase transitions in polyelectrolyte-surfactant complexes formed between a cationic azobenzene-containing surfactant and two types of polyelectrolytes: natural (DNA) or synthetic (PAA: poly acrylic acid). The construction of a phase diagram allowed distancing between four major phases: extended coil conformation, colloidally stable compacted globules, colloidal instability range, and surfactant-stabilized compact state. Investigation on the complexes' properties in different phases and under irradiation with UV light provides information about the role of the surfactant's hydrophobic trans isomers both in the formation and destruction of DNA and PAA globules as well as in their colloidal stabilization. The trans isomer shows much stronger affinity to the polyelectrolytes than the hydrophilic cis counterpart. There is no need for complete compensation of the polyelectrolyte charges to reach the complete compaction. On contrary to the findings previously reported in the literature, we demonstrate - for the first time - complete polyelectrolyte compaction which occurs already at 20% of DNA (and at 50% of PAA) charge compensation. The trans isomer plays the main role in the compaction. The aggregation between azobenzene units in the photosensitive surfactant is a driving force of this process. The decompaction can be realized during UV light irradiation and is strongly influenced by the interplay between surfactant-surfactant and surfactant-DNA interactions in the compacted globules. PMID:25669583

  19. Interaction of photosensitive surfactant with DNA and poly acrylic acid

    SciTech Connect

    Zakrevskyy, Yuriy Paasche, Jens; Lomadze, Nino; Santer, Svetlana; Cywinski, Piotr; Cywinska, Magdalena; Reich, Oliver; Löhmannsröben, Hans-Gerd

    2014-01-28

    In this paper, we investigate interactions and phase transitions in polyelectrolyte-surfactant complexes formed between a cationic azobenzene-containing surfactant and two types of polyelectrolytes: natural (DNA) or synthetic (PAA: poly acrylic acid). The construction of a phase diagram allowed distancing between four major phases: extended coil conformation, colloidally stable compacted globules, colloidal instability range, and surfactant-stabilized compact state. Investigation on the complexes’ properties in different phases and under irradiation with UV light provides information about the role of the surfactant's hydrophobic trans isomers both in the formation and destruction of DNA and PAA globules as well as in their colloidal stabilization. The trans isomer shows much stronger affinity to the polyelectrolytes than the hydrophilic cis counterpart. There is no need for complete compensation of the polyelectrolyte charges to reach the complete compaction. On contrary to the findings previously reported in the literature, we demonstrate – for the first time – complete polyelectrolyte compaction which occurs already at 20% of DNA (and at 50% of PAA) charge compensation. The trans isomer plays the main role in the compaction. The aggregation between azobenzene units in the photosensitive surfactant is a driving force of this process. The decompaction can be realized during UV light irradiation and is strongly influenced by the interplay between surfactant-surfactant and surfactant-DNA interactions in the compacted globules.

  20. In vivo testing of the protection of gloves against acrylates in dentin-bonding systems on patients with known contact allergy to acrylates.

    PubMed

    Andersson, T; Bruze, M; Björkner, B

    1999-11-01

    Occupational contact allergies to dental acrylates are increasing. Commonly used gloves protect poorly against acrylates. The protective efficacy in vivo of other, newer glove materials is not fully known. In this study, an open chamber system was used for testing the protection in vivo of 6 different gloves (1 vinyl glove, 2 latex gloves, 2 nitrile gloves and the 4H glove) against a commonly used dental adhesive, Scotchbond 1, containing 2-hydroxyethyl methacrylate (2-HEMA) and triethylene glycol dimethacrylate (TREGDMA). 8 patients with known contact allergy to 2-HEMA participated. Provocation with 50 microl of the adhesive for 7.5, 15 and 30 min was performed for each glove. The test demonstrated clear differences in the protective efficacy between the gloves. The 4H glove gave by far the best protection, followed by one of the nitrile gloves. One of the latex gloves and the vinyl glove gave a very poor protection against the adhesive. A dose-response relationship was observed between different application times of the acrylate product. The test model promises to be a useful clinical complement to in vitro methods in individual preventive measures against contact sensitization to acrylates. PMID:10554058

  1. Degradation of back surface acrylic mirrors for low concentration and mirror-augmented photovoltaics

    NASA Astrophysics Data System (ADS)

    Murray, Myles P.; Bruckman, Laura S.; Gordon, Devin; Richardson, Samuel; Reinbolt, Greg; Schuetz, Mark; French, Roger H.

    2012-10-01

    Back-surface acrylic mirrors can be used in low concentration and mirror augmented photovoltaics (LCPV, MAPV) to increase the irradiance on a module. Back-surface mirrors can spectrally filter incoming solar radiation reducing the ultraviolet (UV) and infrared (IR) load on the module, while useful radiation is coupled into a module or photovoltaic cell. Degradation of these mirrors can occur from UV induced photodegradative processes and metallization corrosion. Environmental stresses such as humidity, thermal cycling and exposure to corrosive substances can cause an increase in scattering, reducing mirror performance. In order to increase the lifetime and durability of back-surface acrylic mirrors a better understanding of the degradation modes is necessary. In a study of acrylic back-surface mirrors for LCPV and MAPV applications, optical properties and bidirectional scattering distribution functions (BSDF) were investigated and correlated to simulated exposure protocols. Formulations of Poly(methyl methacrylate) (PMMA) with differing concentration of UV absorbers were used for the aluminum backsurface acrylic mirrors. The formulations of aluminum back-surface acrylic mirrors were exposed in a QUV accelerated weathering tester (QLabs) to ASTM G154 Cycle 4. Total and diffuse reflectance spectra were measured for each mirror under exposure using a diffuse reflectance accessory (DRA) from 180-1800 nm on a Varian Cary 6000i at defined dose intervals. The total reflectance losses in the 250-400 nm region were greater and diffuse-only reflectance increased for formulations of acrylic mirrors that contained the least amount of UV stabilizer after each dose of QUV exposure. Acrylic back-surface mirrors were exposed to salt fog corrosion and QUV and were analyzed using BSDF. There was an increase in scattering from roughening of the mirror surface after exposure to the corrosive environment.

  2. Effect of light-curing, pressure, oxygen inhibition, and heat on shear bond strength between bis-acryl provisional restoration and bis-acryl repair materials

    PubMed Central

    Shim, Ji-Suk; Lee, Jeong-Yol; Choi, Yeon-Jo; Shin, Sang-Wan

    2015-01-01

    PURPOSE This study aimed to discover a way to increase the bond strength between bis-acryl resins, using a comparison of the shear bond strengths attained from bis-acryl resins treated with light curing, pressure, oxygen inhibition, and heat. MATERIALS AND METHODS Self-cured bis-acryl resin was used as both a base material and as a repair material. Seventy specimens were distributed into seven groups according to treatment methods: pressure - stored in a pressure cooker at 0.2 Mpa; oxygen inhibition- applied an oxygen inhibitor around the repaired material,; heat treatment - performed heat treatment in a dry oven at 60℃, 100℃, or 140℃. The shear bond strength was measured with a universal testing machine, and the shear bond strength (MPa) was calculated from the peak load of failure. A comparison of the bond strength between the repaired specimens was conducted using one-way ANOVA and Tukey multiple comparison tests (α=.05). RESULTS There were no statistically significant differences in the shear bond strength between the control group and the light curing, pressure, and oxygen inhibition groups. However, the heat treatment groups showed statistically higher bond strengths than the groups treated without heat, and the groups treated at a higher temperature resulted in higher bond strengths. Statistically significant differences were seen between groups after different degrees of heat treatment, except in groups heated at 100℃ and 140℃. CONCLUSION Strong bonding can be achieved between a bis-acryl base and bis-acryl repair material after heat treatment. PMID:25722837

  3. Development of carboxymethyl cellulose acrylate for various biomedical applications.

    PubMed

    Pal, Kunal; Banthia, A K; Majumdar, D K

    2006-06-01

    The purpose of this work is to prepare a pH-sensitive hydrogel membrane of sodium carboxymethyl cellulose acrylate for drug delivery and other biomedical applications. The hydrogel was made by esterification of sodium carboxymethyl cellulose (SCMC) and acryloyl chloride (ACl). The esterified product was characterized by FTIR spectroscopy and XRD. Swelling, hemocompatibility, water vapor transmission rate, contact angle and diffusional studies were also done. Biocompatibility of the membrane was established by quantification of cell growth of L929 cells and mice splenocytes. The FTIR spectrum of the hydrogel suggested the formation of ester bonds between the hydroxyl groups of sodium carboxymethyl cellulose and the carbonyl group of acryloyl chloride. Water vapor transmission rate, hemocompatibility, contact angle and swelling studies indicated that the hydrogel can be tried as a wound dressing material. The hydrogel showed pH-dependent swelling behavior arising from the acidic pendant group in the polymer network. The permeability of the hydrogel membrane produced, as shown by salicylic acid diffusion, increased in response to an increase in pH of the external medium. The hydrogel membrane was permeable to salicylic acid at pH 7.2 but not at pH 2.0 (0.01N HCl). The effect of changes of pH on the hydrogel's permeability was found to be reversible. The hydrogel membrane was found to be compatible with the L929 mice fibroblast cell line and mice splenocytes. The esterified product of SCMC and ACl swells on increase of pH indicating its possible use in a pH-sensitive drug delivery system and as a wound dressing material. PMID:18460761

  4. Hemocompatibility of Chitosan/poly(acrylic acid) Grafted Polyurethane Tubing

    PubMed Central

    Lee, Hyun-Su; Tomczyk, Nancy; Kandel, Judith; Composto, Russell J.; Eckmann, David M.

    2013-01-01

    The activation and adhesion of platelets or whole blood exposed to chitosan (CH) grafted surfaces is used to evaluate the hemocompatibility of biomaterials. The biomaterial surfaces are polyurethane (PU) tubes grafted with an inner poly(acrylic acid) (PAA) and an outer CH or quaternary ammonium modified CH (CH-Q) brush. The CH, CH-Q and PAA grafted layers were characterized by ellipsometry and fluorescence microscopy. Material wear tests demonstrate that CH (CH-Q) is stably grafted onto PU tubes upon exposure to saline solution for 7 days. Using quartz-crystal microbalances with dissipation (QCM-D), in-situ adsorption of blood plasma proteins on CH and CH-Q compared to a silicon oxide control was measured. The QCM-D results showed that the physically adsorbed plasma protein layer on CH-Q and CH surfaces is softer and more viscous than the protein layer on the SiO2 surface. The CH-Q layer thus has the weakest interaction with plasma proteins. Whole blood and platelet adhesion was reduced by ~92% on CH-Q, which showed the weakest interaction with plasma protein but more viscous adsorbed plasma protein layer, compared to SiO2. Last, to examine the biologic response of platelets and neutrophils to biomaterial surfaces, CH (CH-Q)/PAA, PAA and PU tubes were tested using a Chandler Loop apparatus as an ex vivo model and flow cytometry. The blood adhesion and biologic response results showed that CH and CH-Q reduced adhesion and activation of platelets and neutrophils and improved hemocompatibility relative to other surfaces (PU and PAA). Our studies demonstrated that the properties of physically adsorbed plasma protein layer on biomaterial surfaces correlates with blood coagulation on biomaterial surfaces. PMID:24349719

  5. Development of carboxymethyl cellulose acrylate for various biomedical applications

    NASA Astrophysics Data System (ADS)

    Pal, Kunal; Banthia, A. K.; Majumdar, D. K.

    2006-06-01

    The purpose of this work is to prepare a pH-sensitive hydrogel membrane of sodium carboxymethyl cellulose acrylate for drug delivery and other biomedical applications. The hydrogel was made by esterification of sodium carboxymethyl cellulose (SCMC) and acryloyl chloride (ACl). The esterified product was characterized by FTIR spectroscopy and XRD. Swelling, hemocompatibility, water vapor transmission rate, contact angle and diffusional studies were also done. Biocompatibility of the membrane was established by quantification of cell growth of L929 cells and mice splenocytes. The FTIR spectrum of the hydrogel suggested the formation of ester bonds between the hydroxyl groups of sodium carboxymethyl cellulose and the carbonyl group of acryloyl chloride. Water vapor transmission rate, hemocompatibility, contact angle and swelling studies indicated that the hydrogel can be tried as a wound dressing material. The hydrogel showed pH-dependent swelling behavior arising from the acidic pendant group in the polymer network. The permeability of the hydrogel membrane produced, as shown by salicylic acid diffusion, increased in response to an increase in pH of the external medium. The hydrogel membrane was permeable to salicylic acid at pH 7.2 but not at pH 2.0 (0.01N HCl). The effect of changes of pH on the hydrogel's permeability was found to be reversible. The hydrogel membrane was found to be compatible with the L929 mice fibroblast cell line and mice splenocytes. The esterified product of SCMC and ACl swells on increase of pH indicating its possible use in a pH-sensitive drug delivery system and as a wound dressing material.

  6. Hemocompatibility of Chitosan/poly(acrylic acid) Grafted Polyurethane Tubing.

    PubMed

    Lee, Hyun-Su; Tomczyk, Nancy; Kandel, Judith; Composto, Russell J; Eckmann, David M

    2013-12-14

    The activation and adhesion of platelets or whole blood exposed to chitosan (CH) grafted surfaces is used to evaluate the hemocompatibility of biomaterials. The biomaterial surfaces are polyurethane (PU) tubes grafted with an inner poly(acrylic acid) (PAA) and an outer CH or quaternary ammonium modified CH (CH-Q) brush. The CH, CH-Q and PAA grafted layers were characterized by ellipsometry and fluorescence microscopy. Material wear tests demonstrate that CH (CH-Q) is stably grafted onto PU tubes upon exposure to saline solution for 7 days. Using quartz-crystal microbalances with dissipation (QCM-D), in-situ adsorption of blood plasma proteins on CH and CH-Q compared to a silicon oxide control was measured. The QCM-D results showed that the physically adsorbed plasma protein layer on CH-Q and CH surfaces is softer and more viscous than the protein layer on the SiO2 surface. The CH-Q layer thus has the weakest interaction with plasma proteins. Whole blood and platelet adhesion was reduced by ~92% on CH-Q, which showed the weakest interaction with plasma protein but more viscous adsorbed plasma protein layer, compared to SiO2. Last, to examine the biologic response of platelets and neutrophils to biomaterial surfaces, CH (CH-Q)/PAA, PAA and PU tubes were tested using a Chandler Loop apparatus as an ex vivo model and flow cytometry. The blood adhesion and biologic response results showed that CH and CH-Q reduced adhesion and activation of platelets and neutrophils and improved hemocompatibility relative to other surfaces (PU and PAA). Our studies demonstrated that the properties of physically adsorbed plasma protein layer on biomaterial surfaces correlates with blood coagulation on biomaterial surfaces. PMID:24349719

  7. The effect of various frequencies of ultrasonic cleaner in reducing residual monomer in acrylic resin.

    PubMed

    Charasseangpaisarn, Taksid; Wiwatwarrapan, Chairat

    2015-12-01

    Monomer remaining in denture base acrylic can be a major problem because it may cause adverse effects on oral tissue and on the properties of the material. The purpose of this study was to compare the effect of various ultrasonic cleaner frequencies on the amount of residual monomer in acrylic resin after curing. Forty-two specimens each of Meliodent heat-polymerized acrylic resin (M) and Unifast Trad Ivory auto-polymerized acrylic resin (U) were prepared according to their manufacturer's instructions and randomly divided into seven groups: Negative control (NC); Positive control (PC); and five ultrasonic treatment groups: 28 kHz (F1), 40 kHz (F2), 60 kHz (F3) (M=10 min, U=5 min), and 28 kHz followed by 60 kHz (F4: M=5 min per frequency, U=2.5 min per frequency, and F5: M=10 min followed by 5 min per frequency, U=5 min followed by 2.5 min per frequency). Residual monomer was determined by HPLC following ISO 20795-1. The data were analyzed by One-way ANOVA and Tukey HSD. There was significantly less residual monomer in the auto-polymerized acrylic resin in all ultrasonic treatment groups and the PC group than that of the NC group (p<0.05). However, the amount of residual monomer in group F3 was significantly higher than that of the F1, F4, and PC groups (p<0.05). In contrast, ultrasonic treatment did not reduce the amount of residual monomer in heat-polymerized acrylic resin (p>0.05). The amount of residual monomer in heat-polymerized acrylic resin was significantly lower than that of auto-polymerized acrylic resin. In conclusion, ultrasonic treatment at low frequencies is recommended to reduce the residual monomer in auto-polymerized acrylic resin and this method is more practical in a clinical situation than previously recommended methods because of reduced chairside time. PMID:26190059

  8. Graft Polymerization of Acrylic Acid on a Polytetrafluoroethylene Panel by an Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Lan, Yan; You, Qingliang; Cheng, Cheng; Zhang, Suzhen; Ni, Guohua; Nagatsu, M.; Meng, Yuedong

    2011-02-01

    Surface modification on a polytetrafluoroethylene (PTFE) panel was performed with sequential nitrogen plasma treatments and surface-initiated polymerization. By introducing COO- groups to the surface of the PTFE panel through grafting polymerization of acrylic acid (AA), a transparent poly (acrylic acid) (PAA) membrane was achieved from acrylic acid solution. Grafting polymerization initiating from the active groups was achieved on the PTFE panel surface after the nitrogen plasma treatment. Utilizing the acrylic acid as monomers, with COO- groups as cross link sites to form reticulation structure, a transparent poly (acrylic acid) membrane with arborescent macromolecular structure was formed on the PTFE panel surface. Analysis methods, such as fourier transform infrared spectroscopy (FTIR), microscopy and X-ray photoelectron spectroscopy (XPS), were utilized to characterize the structures of the macromolecule membrane on the PTFE panel surface. A contact angle measurement was performed to characterize the modified PTFE panels. The surface hydrophilicities of modified PTFE panels were significantly enhanced after the plasma treatment. It was shown that the grafting rate is related to the treating time and the power of plasma.

  9. Conversion of (Meth)acrylic acids to methane granular sludge: Initiation by specific anerobic microflora

    SciTech Connect

    Shtarkman, N.B.; Obraztova, A.Y.; Laurinavichyus, K.S.; Galushko, A.S.; Akimenko, V.K.

    1995-03-01

    The role of a specific anaerobic microflora in the initiation of degradation of (meth)acrylic acids to methane by granular sludge from a UASB reactor was investigated. Associations of anaerobic bacteria isolated from the anaerobic sludge, which was used for a long time for treatment of wastewater from (meth)acrylate production, were able to realize the initial stage of (meth)acrylic acid decomposition, i.e., a conversion of acrylic and methacrylic acids to propionic and isobutyric acids, respectively. When added to granules, these association played a role of an {open_quotes}initiator{close_quotes} of the degradation process, which was then continued by the granular sludge microflora utilizing propionate and isobutyrate. Some characteristics of the granules adapted to propionate or isobutyrate are presented. The rates of propionate and isobutyrate consumption by adapted granules is, respectively, 21 and 53 times higher than the values obtained for nonadapted granules. A combined use of {open_quotes}initiating{close_quotes} bacteria and adapted granules provided degradation of (meth)acrylic acids with a maximum methane yield. The possibility is discussed of employing the granules, which are adapted to short-chain fatty acids, and the {open_quotes}initiating{close_quotes} bacteria, which accomplish the initial steps of the organic material decomposition to lower fatty acids, for the conversion of various chemical compounds to methane. 10 refs., 3 figs., 2 tabs.

  10. Synthesis of a novel acrylated abietic acid-g-bacterial cellulose hydrogel by gamma irradiation.

    PubMed

    Abeer, Muhammad Mustafa; Amin, Mohd Cairul Iqbal Mohd; Lazim, Azwan Mat; Pandey, Manisha; Martin, Claire

    2014-09-22

    Acrylated abietic acid (acrylated AbA) and acrylated abietic acid-grafted bacterial cellulose pH sensitive hydrogel (acrylated AbA-g-BC) were prepared by a one-pot synthesis. The successful dimerization of acrylic acid (AA) and abietic acid (AbA) and grafting of the dimer onto bacterial cellulose (BC) was confirmed by 13C solid state NMR as well as FT-IR. X-ray diffraction analysis showed characteristic peaks for AbA and BC; further, there was no effect of increasing amorphous AA content on the overall crystallinity of the hydrogel. Differential scanning calorimetry revealed a glass transition temperature of 80°C. Gel fraction and swelling studies gave insight into the features of the hydrogel, suggesting that it was suitable for future applications such as drug delivery. Scanning electron microscopy observations showed an interesting interpenetrating network within the walls of hydrogel samples with the lowest levels of AA and gamma radiation doses. Cell viability test revealed that the synthesized hydrogel is safe for future use in biomedical applications. PMID:24906785

  11. [Hydrogen peroxide, chloramine T and chlorhexidrine in the disinfection of acrylic resin].

    PubMed

    Czerwińska, W; Kedzia, A; Kałowski, M

    1978-01-01

    The effectiveness of 3% h drogen peroxide, 5% chloramine T and 0,5% chlorhexidine gluconate solutions in disinfection of acrylic resine plates massively infected with oral flora was analysed. The acrylic resine plates used for investigations, were infected in vitro with mixed salivary flora characterized by small numbers of yeast-like fungi (1st group), or great number of these microorganisms (2nd group). Infected plates were exposed to solutions of analysed disinfectants during various time periods. After rinsing or inactivation of disinfectant residues, acrylic plates were put into bacteriological medium and incubated during 7 days period in 37 degrees C. The results of this study indicated the effectiveness of acrylic plates disinfection to be dependent on used disinfectant, time of exposition, and microorganisms present on the surface of acrylic resine. The solutions of disinfectants were less active in the cases of plates infected with material containing great numbers of yeast-like microorganisms. Among analysed disinfectants 0,5% solution of chlorhexidine was characterized by most effective and rapid activity, whereas 3% solution of hydrogen peroxide was found to be the least effective. PMID:364448

  12. In Vitro Antifungal Evaluation of Seven Different Disinfectants on Acrylic Resins

    PubMed Central

    Yildirim-Bicer, A. Z.; Peker, I.; Akca, G.; Celik, I.

    2014-01-01

    Objective. The aim of this study was to evaluate alternative methods for the disinfection of denture-based materials. Material and Methods. Two different denture-based materials were included in the study. Before microbial test, the surface roughness of the acrylic resins was evaluated. Then, the specimens were divided into 8 experimental groups (n = 10), according to microorganism considered and disinfection methods used. The specimens were contaminated in vitro by standardized suspensions of Candida albicans ATCC#90028 and Candida albicans oral isolate. The following test agents were tested: sodium hypochlorite (NaOCl 1%), microwave (MW) energy, ultraviolet (UV) light, mouthwash containing propolis (MCP), Corega Tabs, 50% and 100% white vinegar. After the disinfection procedure, the number of remaining microbial cells was evaluated in CFU/mL. Kruskal-Wallis, ANOVA, and Dunn's test were used for multiple comparisons. Mann Whitney U test was used to compare the surface roughness. Results. Statistically significant difference (P < 0.05) was found between autopolymerised and heat-cured acrylic resins. The autopolymerised acrylic resin surfaces were rougher than surfaces of heat-cured acrylic resin. The most effective disinfection method was 100% white vinegar for tested microorganisms and both acrylic resins. Conclusion. This study showed that white vinegar 100% was the most effective method for tested microorganisms. This agent is cost-effective and easy to access and thus may be appropriate for household use. PMID:24995305

  13. The electrospinning of the copolymer of styrene and butyl acrylate for its application as oil absorbent.

    PubMed

    Xu, Naiku; Cao, Jipeng; Lu, Yuyao

    2016-01-01

    Electrospun polystyrene materials have been employed as oil absorbents, but they have visible drawbacks such as poor strength at low temperature and unreliable integrity because of brittleness and insufficient cohesive force among fibers. Butyl acrylate can polymerize into flexible chains, and its polymer can be used as elastomer and adhesive material. Thereby it is possible to obtain the material that has better performance in comparison with electrospun polystyrene material through the electrospinning of the copolymer of styrene and butyl acrylate. In this work, a polymer was synthesized through suspension polymerization by using styrene and butyl acrylate as comonomers. The synthesis of the copolymer of styrene and butyl acrylate was verified through dissolution and hydrolysis experimental data; as well through nuclear magnetic resonance spectrometry. The viscous flow activation energy of the solution consisting of copolymer and N, N-dimethylformamide was determined via viscosity method and then adopted to establish the entanglement characteristics of butyl acrylate's chain segments. Finally, in order to electrospin the copolymer solution into fibrous membrane, the effects of monomer feed ratio and spinning parameters were investigated. The prepared fibrous membrane was found to have a potential use as oil absorbent. PMID:27610302

  14. Radiation modification of water absorption of cassava starch by acrylic acid/acrylamide

    NASA Astrophysics Data System (ADS)

    Kiatkamjornwong, Suda; Chomsaksakul, Wararuk; Sonsuk, Manit

    2000-10-01

    Graft copolymerizations of acrylamide and/or acrylic acid onto cassava starch by a simultaneous irradiation technique using gamma-rays as the initiator were studied with regard to various parameters of importance: the monomer-to-cassava starch ratio, total dose (kGy), dose rate (kGy h -1), acrylamide-to-acrylic acid ratio, and the addition of nitric acid and maleic acid as the additives. Grafting parameters were determined in relation to the water absorption of the saponified graft copolymer. The water absorption of the saponified graft copolymer in salt and buffer solutions of different ionic strengths was also measured, from which the superabsorbent properties are found to be pH sensitive. The starch graft copolymers of acrylamide and acrylic acid give higher water absorption than the starch graft copolymers of either acrylamide or acrylic acid alone. The porosity of the saponified starch graft copolymers prepared by the acrylamide/acrylic acid ratios of 70:30 and 50:50 was much higher than the porosity of copolymers in terms of fine networks. Ionic strength and multi-oxidation states of the saline and buffer solutions markedly decreased the water absorption of the saponified cassava starch grafted superabsorbent polymers.

  15. New blends of ethylene-butyl acrylate copolymers with thermoplastic starch. Characterization and bacterial biodegradation.

    PubMed

    Morro, A; Catalina, F; Corrales, T; Pablos, J L; Marin, I; Abrusci, C

    2016-09-20

    Ethylene-butyl acrylate copolymer (EBA) with 13% of butyl acrylate content was used to produce blends with 10, 30 and 60% of thermoplastic starch (TPS) plasticized with glycerol. Ethylene-acrylic acid copolymer (EAA) was used as compatibilizer at 20% content with respect to EBA. The blends were characterized by X-ray diffraction, ATR-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), water-Contact Angle measurements (CA), Differential Scanning Calorimetry (DSC) and Stress-strain mechanical tests. Initiated autoxidation of the polymer blends was studied by chemiluminescence (CL) confirming that the presence of the polyolefin-TPS interphase did not substantially affect the oxidative thermostability of the materials. Three bacterial species have been isolated from the blend films buried in soil and identified as Bacillus subtilis, Bacillus borstelensis and Bacillus licheniformis. Biodegradation of the blends (28days at 45°C) was evaluated by carbon dioxide measurement using the indirect impedance technique. PMID:27261731

  16. Catalytic production of methyl acrylates by gold-mediated cross coupling of unsaturated aldehydes with methanol

    NASA Astrophysics Data System (ADS)

    Karakalos, Stavros; Zugic, Branko; Stowers, Kara J.; Biener, Monika M.; Biener, Juergen; Friend, Cynthia M.; Madix, Robert J.

    2016-10-01

    Modern methods of esterification, one of the most important reactions in organic synthesis, are reaching their limits, as far as waste and expense are concerned. Novel chemical approaches to ester formation are therefore of importance. Here we report a simple procedure free of caustic reagents or byproducts for the facile direct oxidative methyl esterification of aldehydes over nanoporous Au catalysts. Complementary model studies on single crystal gold surfaces establish the fundamental reactions involved. We find that methanol more readily reacts with adsorbed active oxygen than do the aldehydes, but that once the aldehydes do react, they form strongly-bound acrylates that block reactive sites and decrease the yields of acrylic esters under steady flow conditions at 420 K. Significant improvements in yield can be achieved by operating at higher temperatures, which render the site-blocking acrylates unstable.

  17. Stress distribution associated with loaded acrylic-metal-cement crowns by using finite element method.

    PubMed

    Toparli, M; Aykul, H; Aksoy, T

    2002-11-01

    The axisymmetrical finite element method (FEM) was used to compare stress distribution in a maxillary second premolar restored tooth. The three models were evaluated by crowning the tooth with Au-Pd alloy, Ni-Cr alloy and Ti alloy with acrylic. A longitudinal static force, 200 N in magnitude at an angle of 45 degrees was applied on the occlusal margin of each model. The tooth was assumed isotropic, homogenous and elastic. This numerical study was carried out using axisymmetric finite element models and calculation programmes were prepared by the authors using FORTRAN 77. Comparison of stress distributions was made in four regions of apex, cole, dentin-metal interface and metal-acrylic interface. The highest stress values were obtained when NiCr alloy with acrylic was used. PMID:12453266

  18. Nitrile Hydratase and Amidase from Rhodococcus rhodochrous Hydrolyze Acrylic Fibers and Granular Polyacrylonitriles

    PubMed Central

    Tauber, M. M.; Cavaco-Paulo, A.; Robra, K.-H.; Gübitz, G. M.

    2000-01-01

    Rhodococcus rhodochrous NCIMB 11216 produced nitrile hydratase (320 nkat mg of protein−1) and amidase activity (38.4 nkat mg of protein−1) when grown on a medium containing propionitrile. These enzymes were able to hydrolyze nitrile groups of both granular polyacrylonitriles (PAN) and acrylic fibers. Nitrile groups of PAN40 (molecular mass, 40 kDa) and PAN190 (molecular mass, 190 kDa) were converted into the corresponding carbonic acids to 1.8 and 1.0%, respectively. In contrast, surfacial nitrile groups of acrylic fibers were only converted to the corresponding amides. X-ray photoelectron spectroscopy analysis showed that 16% of the surfacial nitrile groups were hydrolyzed by the R. rhodochrous enzymes. Due to the enzymatic modification, the acrylic fibers became more hydrophilic and thus, adsorption of dyes was enhanced. This was indicated by a 15% increase in the staining level (K/S value) for C.I. Basic Blue 9. PMID:10742253

  19. [MORPHOLOGICAL FEATURES OF RAT MUCOUS MEMBRANE OF THE TONGUE EARLY AFFECTED BY ACRYLIC RESIN MONOMER].

    PubMed

    Davydenko, V; Nidzelskiy, M; Starchenko, I; Davydenko, A; Kuznetsov, V

    2016-03-01

    Base materials, made on the basis of various derivatives of acrylic and methacrylic acids, have been widely used in prosthetic dentistry. Free monomer, affecting the tissues of prosthetic bed and the whole body, is always found in dentures. Therefore, study of the effect of acrylic resins' monomer on mucous membrane of the tongue is crucial. Rat tongue is very similar to human tongue, and this fact has become the basis for selecting these animals to be involved into the experiment. The paper presents the findings related to the effect of "Ftoraks" base acrylic resin monomer on the state of rat mucous membrane of the tongue and its regeneration. The microscopy has found that the greatest changes in the mucous membrane of the tongue occur on day 3 and 7 day after applying the monomer and are of erosive and inflammatory nature. Regeneration of tongue epithelium slows down. PMID:27119844

  20. Radiation synthesis of superabsorbent poly(acrylic acid)-carrageenan hydrogels

    NASA Astrophysics Data System (ADS)

    Francis, Sanju; Kumar, Manmohan; Varshney, Lalit

    2004-04-01

    A series of superabsorbent hydrogels were prepared from carrageenan and partially neutralized acrylic acid by gamma irradiation at room temperature. The gel fraction, swelling kinetics and the equilibrium degree of swelling (EDS) of the hydrogels were studied. It was found that the incorporation of even 1% carrageenan (sodium salt) increases the EDS of the hydrogels from ˜320 to ˜800 g/g. Thermal analysis were carried out to determine the amount of free water and bound water in the hydrogels. Under optimum conditions, poly(acrylic acid)-carrageenan hydrogels with high gel fraction (˜80%) and very high EDS (˜800 g/g) were prepared gamma radiolytically from aqueous solution containing 15% partially neutralized acrylic acid and 1-5% carrageenan. The hydrogels were also found to be sensitive to the pH and the ionic strength of the medium.

  1. Applications of Blue Light-curing Acrylic Resin to Forensic Sample Preparation and Microtomy.

    PubMed

    Groves, Ethan; Palenik, Christopher S

    2016-03-01

    This study discusses the results of an evaluation of a one-part blue light-curing acrylic resin for embedding trace evidence prior to the preparation of thin sections with a microtome. Through a comparison to several epoxy resins, the physical properties relevant to both trace evidence examination and analytical microscopy in general, including as viscosity, clarity, color, hardness, and cure speed, were explored. Finally, thin sections from paint samples embedded in this acrylic resin were evaluated to determine if, through smearing or impregnation, the resin contributed to the infrared spectra. The results of this study show that blue light-curing acrylic resins provide the desired properties of an embedding medium, generate high-quality thin sections, and can significantly simplify the preparation of paint chips, fibers and a multitude of other types of microscopic samples in the forensic trace evidence laboratory. PMID:27404623

  2. Synthesis of radiation crosslinked poly(acrylic acid) in the presence of phenyltriethoxysilane

    NASA Astrophysics Data System (ADS)

    Hassan, Safia; Yasin, Tariq

    2014-04-01

    Acrylic acid based superabsorbent hydrogel was prepared using phenyltriethoxysilane (PTES) as polyfunctional monomer. Different amounts of PTES were incorporated in acrylic acid and irradiated at different doses upto maximum of 30 kGy. The crosslinked acrylic acid showed hydrogel properties and its swelling kinetics, gel fraction and equilibrium degree of swelling (EDS) were studied. It was found that the increased PTES concentration decreased the EDS of the hydrogels. Infrared spectroscopy confirmed the crosslinking reaction between the feed components and the existence of siloxane bond. Thermogravimetric analysis showed an increase in the stability of the hydrogels having high PTES content. The swelling of the hydrogel was affected by pH, ionic strength and temperature. These hydrogels showed low swelling in acidic and basic pH range and high swelling around neutral pH. This switchable pH response of these hydrogels can be exploited in environmental and biomedical applications.

  3. Pathogenesis of neurotoxicity of acrylates acrylonitrile and acrylamide: from cell to organism.

    PubMed

    Tarskikh, M M; Klimatskaya, L G; Kolesnikov, S I

    2013-08-01

    The incubation of 10 mM acrylamide (in vitro) with rat brain homogenate was followed by a decrease in catalase activity by 48% as soon as 5 min after addition of acrylate to the incubation medium. Activity of this enzyme remained low 30 min after the start of the experiment. Acute poisoning with this acrylate was accompanied by LPO activation in rat brain 24 h after injection. Exposure to acrylonitrile during occupational contacts with this monomer was followed by accumulation of adducts of acrylate with erythrocytic hemoglobin in human blood. In accordance with previously observed data, modern scheme of neurotropic effects of acrylonitrile and acrylamide was proposed. This scheme explained specific features of clinical syndromes induced by acute and chronic exposure to these toxic agents. PMID:24143365

  4. Designing ultraviolet curing of multifunctional (meth)acrylate hard coats

    NASA Astrophysics Data System (ADS)

    Wen, Mei

    Ultraviolet (UV) curing rapidly converts multifunctional (meth)acrylate liquid monomers into highly cross-linked, impervious, hard polymeric coatings at ambient temperature. This solidification process occurs by free-radical cross-linking polymerization. To achieve a better design of this process, it is desirable to have high conversion of functional groups, low stress, adequate mechanical properties, and low costs. To approach this design goal, the following modeling and experimental work was carried out. Firstly, a kinetic model was developed to simulate radical trapping. This model predicts a peak in the concentration of active radicals and a monotonic rise of the concentration of trapped radicals during polymerization. It also predicts a decrease in the fraction of trapped radicals at a given conversion as the UV light intensity is raised. Secondly, a kinetic gelation model, in which reaction occurs locally on a lattice, was developed. Unlike previous such models, this model accounts for free radical reaction time more accurately. It was found that a more uniform distribution of reacted sites leads to a favored propagation at a given conversion. Moreover, radical trapping and termination were found to shorten the kinetic chain length and to lower the asymptotic conversion reached when initiators are exhausted. Thirdly, elastic modulus evolution was simulated with a rigidity percolation model, in which bonds created by free-radical polymerization are represented as rigidly jointed beams. Simulations show that modulus of a network depends on the connectivity between monomer units as well as bonding structure. Finally, experimental determination of volume shrinkage of a sandwiched film was measured with a dynamic mechanical analyzer probe. A faster reaction causes more severely delayed volume shrinkage from the thermodynamic equilibrium volume required by the reaction. Nevertheless, volume shrinks more when the shrinkage of the thermodynamic volume rises. In

  5. Synthesis and molecular characterization of acrylate liquid crystalline resin monomers (ALCRM).

    PubMed

    He, X P; Cai, W; Guo, L; Zhou, L Z; Nie, M H

    2015-01-01

    A novel biocompatible resin monomer 4—3—(acryloyloxy)—2—hydroxypropoxy) phenyl 4—(3—(acryloyloxy)—2—hydroxypropoxy) benzoate, as an oral restorative — acrylate liquid crystalline resin monomer (ALCRM) was synthesized. The intermediate product and the final product were characterized by differential scanning calorimetry (DSC), polarized optical microscope (POM), and nuclear magnetic resonance (NMR). A resin matrix which has a potential application in dental composites was prepared by photopolymerizing ALCRM and triethylene glycol dimethacrylate (TEGDMA) as a primary and diluted monomer with a photosensitizer of camphorquinone (CQ) and 2—(Dimethylamino)ethyl methacrylate (DMAEMA) mixture. The molar ratio of ALCRM and TEGDMA was 7:3. The properties such as the curing depth, curing time, and the volumetric shrinkage of the resin matrix were investigated and compared with a traditional composite resin matrix Bis—GMA. After photocuring polymerization, the conversion degree of the resin matrix is 68.06%, higher than Bis—GMA/TEGDMA; the curing time is 4.08±0.20min, the curing depth is 2.10±0.17mm, and the volumetric shrinkage is 3.62%±0.26%. All the properties exhibit a better performance of the prepared resin matrix than Bis—GMA. PMID:26475389

  6. Inhibiting electro-thermal breakdown of acrylic dielectric elastomer actuators by dielectric gel coating

    NASA Astrophysics Data System (ADS)

    La, Thanh-Giang; Lau, Gih-Keong

    2016-01-01

    Electrical breakdown of dielectric elastomer actuators (DEA) is very localized; a spark and a pinhole (puncture) in dielectric ends up with short-circuit. This letter shows that prevention of electrothermal breakdown helps defer failure of DEAs even with conductive-grease electrodes. Dielectric gel encapsulation or coating (Dow Corning 3-4170) helps protect acrylic elastomer (VHB 4905), making it thermally more stable and delaying its thermal oxidation (burn) from 218 °C to 300 °C. Dielectric-gel-coated acrylic DEAs can withstand higher local leak-induced heating and thus achieve higher dielectric strengths than non-coated DEAs do.

  7. The fabrication of wavelength shifting lightguides from clear acrylic sheet by disperse dyeing

    NASA Astrophysics Data System (ADS)

    McMillan, J. E.

    2015-06-01

    Wavelength shifting lightguides have found extensive use as a means of collecting scintillation or cherenkov light from large areas onto a smaller area photodetector and for matching the emitted spectrum to the spectral response of the photodetector. Conventionally, such lightguides are fabricated by casting acrylic polymer with the fluorescent dye incorporated in the bulk. A technique has been developed in which plain cast acrylic sheet is disperse dyed in an aqueous bath. The resulting lightguide has the fluorescent dye held in a thin layer at the surface of the material. A number of different fluorescent dyes are demonstrated

  8. Radioluminescence of polyester resin modified with acrylic acid and its salts

    NASA Astrophysics Data System (ADS)

    Szalińska, H.; Wypych, M.; Pietrzak, M.; Szadkowska-Nicze, M.

    Polimal-109 polyester resin and its compounds containing acrylic acid and its salts such as: sodium, potassium, magnesium, calcium, barium, iron, cobalt, copper and manganese acrylates were studied by the radioluminescence method, including isothermal luminescence (ITL) at a radiation temperature of 77 K, thermoluminescence (RTL) and spectral distributions of isothermal luminescence. Measurements of optical absorption at 77 K before and after irradiation of the investigated samples were also carried out. The results obtained have shown that metal ions play a significant part in the processes taking place in the polyester matrix under the influence of γ 60Co radiation.

  9. Chemical Fixation of CO{sub 2} to Acrylates Using Low-Valent Molybdenum Sources

    SciTech Connect

    Bernskoetter, Wesley

    2013-09-30

    The kinetic, mechanistic, and reactivity experiments to access the viability and possible reaction design of coupling of carbon dioxide and ethylene at a zerovalent molybdenum for the production of acrylates are described. A general model of the reaction mechanism has been outlined, including assessment of the rate limiting step in the reaction. Kinetic and computational data have valuated the influence of a range of tridentate ligand platforms on the rate of coupling. An in situ reduction and acrylate formation activity screen protocol has also been developed to aid in the technology development of this process. Portions of descriptions of the research products presented here have also been adapted with permission from journal publications.

  10. Synthesis and physicochemical properties of organofluorine esters of acrylic, methacrylic, and maleic acids

    SciTech Connect

    Gol'din, G.S.; Averbakh, K.O.; Lavygin, I.A.; Nekrasova, L.A.

    1985-12-01

    The authors synthesize and study the physicochemical properties of organofluorine acrylates, methacrylates, and maleates. The organofluorine esters are colorless liquids; their composition and structure were confirmed by elemental analysis and IR spectra. The results of studies of the dependence of the density, surface tension, and viscosity of these compounds on temperature are presented. The results revealed the influence of the length of the fluorocarbon chain on the combination of the physicochemical properties of organofluorine acrylates, methacrylates, and maleates, and also provided a method for estimating certain thermophysical characteristics of such compounds without recourse to experimental measurements.

  11. Crystal structures of (E)-3-(furan-2-yl)-2-phenyl-N-tosyl-acryl-amide and (E)-3-phenyl-2-(m-tol-yl)-N-tosyl-acryl-amide.

    PubMed

    Cheng, Dong; Meng, Xiangzhen; Sheng, Zeyuan; Wang, Shuangming; Duan, Yuanyuan; Li, Ziqian

    2016-06-01

    In the title N-tosyl-acryl-amide compounds, C20H17NO4S, (I), and C23H21NO3S, (II), the conformation about the C=C bond is E. The acryl-amide groups, [-NH-C(=O)-C=C-], are almost planar, with the N-C-C=C torsion angle being -170.18 (14)° in (I) and -168.01 (17)° in (II). In (I), the furan, phenyl and 4-methyl-benzene rings are inclined to the acryl-amide mean plane by 26.47 (11), 69.01 (8) and 82.49 (9)°, respectively. In (II), the phenyl, 3-methyl-benzene and 4-methyl-benzene rings are inclined to the acryl-amide mean plane by 11.61 (10), 78.44 (10) and 78.24 (10)°, respectively. There is an intra-molecular C-H⋯π inter-action present in compound (II). In the crystals of both compounds, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. In (I), the dimers are reinforced by C-H⋯O hydrogen bonds and linked by C-H⋯π inter-actions, forming chains along [011]. In the crystal of (II), the dimers are linked via C-H⋯O hydrogen bonds, forming chains along [100]. The chains are further linked by C-H⋯π inter-actions, forming layers parallel to (010). PMID:27308045

  12. Thermoresponsive hyperbranched copolymer with multi acrylate functionality for in situ cross-linkable hyaluronic acid composite semi-IPN hydrogel.

    PubMed

    Dong, Yixiao; Hassan, Waqar; Zheng, Yu; Saeed, Aram Omer; Cao, Hongliang; Tai, Hongyun; Pandit, Abhay; Wang, Wenxin

    2012-01-01

    Thermoresponsive polymers have been widely used for in situ formed hydrogels in drug delivery and tissue engineering as they are easy to handle and their shape can easily conform to tissue defects. However, non-covalent bonding and mechanical weakness of these hydrogels limit their applications. In this study, a physically and chemically in situ cross-linkable hydrogel system was developed from a novel thermoresponsive hyperbranched PEG based copolymer with multi acrylate functionality, which was synthesized via an 'one pot and one step' in situ deactivation enhanced atom transfer radical co-polymerization of poly(ethylene glycol) diacrylate (PEGDA, M(n) = 258 g mol(-1)), poly(ethylene glycol) methyl ether methacrylate (PEGMEMA, M(n )= 475 g mol(-1)) and (2-methoxyethoxy) ethyl methacrylate (MEO(2)MA). This hyperbranched copolymer was tailored to have the lower critical solution temperature to form physical gelation around 37°C. Meanwhile, with high level of acrylate functionalities, a chemically cross-linked gel was formed from this copolymer using thiol functional cross-linker of pentaerythritol tetrakis (3-mercaptopropionate) (QT) via thiol-ene Michael addition reaction. Furthermore, a semi-interpenetrated polymer networks (semi-IPN) structure was developed by combining this polymer with hyaluronic acid (HA), leading to an in situ cross-linkable hydrogel with significantly increased porosity, enhanced swelling behavior and improved cell adhesion and viability both in 2D and 3D cell culture models. PMID:22143908

  13. Possible utilization of acrylic paint and copper phthalocyanine pigment sludge for vermiculture.

    PubMed

    Majumdar, Deepanjan; Buch, Vaidehi; Macwan, Praisy; Patel, Jignesh

    2010-05-01

    Sludge generated from water treatment plants in two different paint and pigment manufacturing industries, one manufacturing CPC Green (copper phthalocyanine green) and the other acrylic (pure and styrene) washable distempers, synthetic enamels, fillers and putties, were used for culturing earthworms (Eisenia foetida Savigny). The possibility of getting a quality vermicompost was also explored. The sludges were used pure and mixed with month-old cow dung at 1:1, 1:2, 1:3, 2:1 and 3:1 ratios (sludge:cow dung). In pure sludges and in the 3:1 ratio, earthworms did not survive. Earthworms had very low survival in CPC Green sludge and its mixtures while acrylic paint sludge was very efficient in supporting worm growth and worm castings were generated quickly. Both sludges were alkaline, non-saline, but had appreciable Ca, Al, Pb, Zn, and Mn. CPC Green had high Cu (12,900 mg kg(-1)) and acrylic paint sludge had high total Cr (155 mg kg(-1)). High Ca and Al in both came from water treatment chemicals (lime and alum), while CPC Green itself is a copper-based pigment. The sludges were suitable for land application with regard to their metal contents, except for Cu in CPC Green. CPC Green did not support proper growth of plants (green gram, Vigna radiata (L). R. Wilcz.), while acrylic paint sludge supported growth in pure form and mixtures with soil. PMID:20124313

  14. Copper-acrylic enamel serves as lubricant for cold drawing of refractory metals

    NASA Technical Reports Server (NTRS)

    Beane, C.; Karasek, F.

    1966-01-01

    Acrylic enamel spray containing metallic copper pigment lubricates refractory metal tubing during cold drawing operations so that the tubing surface remains free from scratches and nicks and does not seize in the die. Zirconium alloys, zirconium, tantalum alloys, niobium alloys, vanandium alloys and titanium alloys have been drawn using this lubricant.

  15. Morphological alteration of microwave disinfected acrylic resins used for dental prostheses

    NASA Astrophysics Data System (ADS)

    Popescu, M. C.; Bita, B. I.; Avram, A. M.; Tucureanu, V.; Schiopu, P.

    2015-02-01

    In this paper we aim to perform a cross section morphological characterization of an acrylic polymer used for dental prostheses subjected to microwave disinfection. The method was largely investigated and the microbiological effectiveness is well established, but there are some issues regarding the in-depth alteration of the material. In our research, the surface roughness is insignificant and the samples were not polished or refined by any means. Two groups of 7 acrylic discs (20 mm diameter, 2 mm thickness) were prepared from a heat-cured powder. Half of the samples embedded a stainless steel reinforcement, in order to observe the changes at the interfaces between the polymer and metallic wire. After the gradual wet microwave treatment, the specimens - including the controls - were frozen in liquid nitrogen and broken into pieces. Fragments were selected for gold metallization to ensure a good contrast for SEM imaging. We examined the samples in cross section employing a high resolution SEM. We have observed the alterations occurred at the surface of the acrylic sample and at the interface with the metallic wire along with the increase of the power and exposure time. The bond configuration of acrylate samples was analysed by FTIR spectrometry.

  16. COMPARISON OF SUBCHRONIC NEUROTOXICITY OF 2-HYDROXYETHYL ACRYLATE AND ACRYLAMIDE IN RATS

    EPA Science Inventory

    The comparative neurotoxicity of subchronic exposure to 2 hydroxyethyl acrylate (HEA) and acrylamide (ACR) was evaluated using a functional observational battery (FOB) and neurohistology. hree dose levels of each compound (HEA: 3, 20, 60 mg/kg; ACR: I, 4, 12 mg/kg) were administe...

  17. Integration of lignin and acrylic monomers towards grafted copolymers by free radical polymerization.

    PubMed

    Liu, Xiaohuan; Xu, Yuzhi; Yu, Juan; Li, Shouhai; Wang, Jifu; Wang, Chunpeng; Chu, Fuxiang

    2014-06-01

    Three kinds of acrylic monomers (2,2,3,4,4,4-hexafluorobutyl methacrylate (HFBMA), methyl methacrylate (MMA) and butyl acrylate (BA)) were utilized to modify the lignin (BBL) by "grafting from" free radical polymerization (FRP), respectively. Calcium chloride/hydrogen peroxide (CaCl2/H2O2) was used as initiator. Effects of monomer type and concentration, initiator concentration and polymerization time on grafting from BBL were studied. Grafting of poly (acrylic monomers) onto BBL was verified by the following characterizations and this synthesis method was found to be high efficient and selective for grafting polymerization of BBL. The presence of the BBL moiety in the backbone also resulted in higher glass transition temperature compared with the homopolymer of each monomer, and some modified copolymers also improved its thermal stability. All modifications made BBL more hydrophobic and the static contact angles of these modified copolymers were above 80°. XPS analysis revealed that the surface of these modified BBL copolymers were dominated by acrylate monomer moiety. Additionally, the BBL-g-PBA copolymers can be used as dispersion modifiers in PLA-based materials to enhance UV absorption. PMID:24742785

  18. Effect of MMA-g-UHMWPE grafted fiber on mechanical properties of acrylic bone cement.

    PubMed

    Yang, J M; Huang, P Y; Yang, M C; Lo, S K

    1997-01-01

    Ultrahigh molecular weight polyethylene (UHMWPE) fibers were treated with argon plasma for 5 min, followed by uv irradiation in methyl methacrylate (MMA)-chloroform solution for 5 h to obtain MMA-g-UHMWPE grafted fiber. The grafting content was estimated by the titration of esterification method. The grafting amount of 5280 nmol/g was the largest for the MMA concentration at 18.75 vol%. To improve the mechanical properties of acrylic bone cement, pure UHMWPE fiber and MMA-g-UHMWPE fiber were added to the surgical Simplex. P radiopaque bone cement. The mechanical properties including tensile strength, tensile modulus, compressive strength, bending strength, and bending stiffness were measured. Dynamic mechanical analysis was also performed. By comparing the effect of the pure UHMWPE fiber and MMA-g-UHMWPE grafted fiber on the mechanical properties of acrylic bone cement, it was found that the acrylic bone cement with MMA-g-UHMWPE grafted fiber had a more significant reinforcing effect than that with untreated UHMWPE fiber. This might be due to the improvement of the interfacial bonding between the grafted fibers and the acrylic bone cement matrix. PMID:9421758

  19. Deep UV patterning of acrylic masters for molding biomimetic dry adhesives

    NASA Astrophysics Data System (ADS)

    Sameoto, D.; Menon, C.

    2010-11-01

    We present a novel fabrication method for the production of biomimetic dry adhesives that allows enormous variation in fiber shapes and sizes. The technology is based on deep-UV patterning of commercial acrylic with semi-collimated light available from germicidal lamps, and combined careful processing conditions, material selection and novel developer choices to produce relatively high-aspect-ratio fibers with overhanging caps on large areas. These acrylic fibers are used as a master mold for subsequent silicone rubber negative mold casting. Because the bulk acrylic demonstrates little inherent adhesion to silicone rubbers, the master molds created in this process do not require any surface treatments to achieve high-yield demolding of interlocked structures. Multiple polymers can be cast from silicone rubber negative molds and this process could be used to structure smart materials on areas over multiple square feet. Using direct photopatterning of acrylic allows many of the desired structures for biomimetic dry adhesives to be produced with relative ease compared to silicon-based molding processes, including angled fibers and hierarchical structures. Optimized fiber shapes for a variety of polymers can be produced using this process, and adhesion measurements on a well-characterized polyurethane, ST-1060, are used to determine the effect of fiber geometry on adhesion performance.

  20. 21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethylene-methyl acrylate copolymer resins. 177.1340 Section 177.1340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and...

  1. 21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene-methyl acrylate copolymer resins. 177.1340 Section 177.1340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS...

  2. 21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-methyl acrylate copolymer resins. 177.1340 Section 177.1340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and...

  3. 21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene-methyl acrylate copolymer resins. 177.1340 Section 177.1340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS...

  4. Long-term testing and properties of acrylic for the Daya Bay antineutrino detectors

    NASA Astrophysics Data System (ADS)

    Krohn, M.; Littlejohn, B. R.; Heeger, K. M.

    2012-08-01

    The Daya Bay reactor antineutrino experiment has recently measured the neutrino mixing parameter sin22θ13 by observing electron antineutrino disappearance over kilometer-scale baselines using six antineutrino detectors at near and far distances from reactor cores at the Daya Bay nuclear power complex. Liquid scintillator contained in transparent target vessels is used to detect electron antineutrinos via the inverse beta-decay reaction. The Daya Bay experiment will operate for about five years yielding a precision measurement of sin22θ13. We report on long-term studies of poly(methyl methacrylate) known as acrylic, which is the primary material used in the fabrication of the target vessels for the experiment's antineutrino detectors. In these studies, acrylic samples are subjected to gaseous and liquid environmental conditions similar to those experienced during construction, transport, and operation of the Daya Bay acrylic target vessels and detectors. Mechanical and optical stability of the acrylic as well as its interaction with detector liquids is reported.

  5. Optical properties and indentation hardness of thin-film acrylated epoxidized oil

    NASA Astrophysics Data System (ADS)

    Rahman, Mohammad Syuhaimi Ab.; Shaktur, Khaled Mohamed; Mohammad, Rahmah; Zalikha, Wan Aimi; Nawi, Norwimie; Mohd, Ahmad Faiza

    2012-02-01

    Epoxy acrylate has been widely used as optical resin for applications such as cladding, the core of a waveguide, and other photonic devices. In this study, sustainable resin from edible oil was used as an alternative to epoxy acrylate. Structural features and the transmission of planar thin-film resin from an ultraviolet-visible spectroscopy (UV-VIS) spectrometer were investigated upon UV exposure. It was found that high transmission still persists for all samples with and without an UV absorber for exposed and unexposed samples. The film was found to absorb strongly below 400 nm. A change in the cut-off wavelength was observed upon exposure. Thin-film hardness and its dynamic indentation in the load-unload mode with different test forces were evaluated. Vickers hardness and the elastic modulus were determined for unacrylated epoxidized soybean oil (ESO) and acrylated epoxidized soybean oil (AESO). It was found that the AESO has a higher Vickers hardness and elastic modulus than those of unacrylated thin film. The Vickers hardness and elastic modulus were found to increase as the applied test force increased. The refractive index, thickness, and modes present were characterized from a spin-coated planar thin film. The refractive index in the transverse electric mode (TE) and transverse magnetic mode (TM) were determined and compared for unacrylated and acrylated epoxidized oil.

  6. Structure-function properties of starch graft poly(methyl acrylate)copolymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spherulites, produced by steam jet-cooking high-amylose starch and oleic acid, were grafted with methyl acrylate, both before and after removal of un-complexed amylopectin. For comparison, granular high-amylose corn starch was graft polymerized in a similar manner. The amount of grafted and ungrafte...

  7. Structure-function properties of starch spherulites grafted with poly(methyl acrylate)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spherulites, produced by steam jet-cooking high-amylose starch and oleic acid, were grafted with methyl acrylate, both before and after removal of un-complexed amylopectin. For comparison, granular high-amylose corn starch was graft polymerized in a similar manner. The amount of grafted and ungrafte...

  8. Effect of silver nanoparticles incorporation on viscoelastic properties of acrylic resin denture base material

    PubMed Central

    Mahross, Hamada Zaki; Baroudi, Kusai

    2015-01-01

    Objective: The objective was to investigate the effect of silver nanoparticles (AgNPs) incorporation on viscoelastic properties of acrylic resin denture base material. Materials and Methods: A total of 20 specimens (60 × 10 × 2 mm) of heat cured acrylic resin were constructed and divided into four groups (five for each), according to the concentration of AgNPs (1%, 2%, and 5% vol.) which incorporated into the liquid of acrylic resin material and one group without additives (control group). The dynamic viscoelastic test for the test specimens was performed using the computerized material testing system. The resulting deflection curves were analyzed by material testing software NEXYGEN MT. Results: The 5% nanoparticles of silver (NAg) had significantly highest mean storage modulus E’ and loss tangent Tan δ values followed by 2% NAg (P < 0.05). For 1% nanosilver incorporation (group B), there were no statistically significant differences in storage modulus E’, lost modulus E” or loss tangent Tan δ with other groups (P > 0.05). Conclusion: The AgNPs incorporation within the acrylic denture base material can improve its viscoelastic properties. PMID:26038651

  9. The bond between acrylic resin denture teeth and the denture base: recommendations for best practice.

    PubMed

    Radford, D R; Juszczyk, A S; Clark, R K F

    2014-02-01

    Failure of the bond between denture teeth and base acrylic resin has been shown to be a cause of denture failure leading to inconvenience and costly repair. The optimal combination of acrylic resin denture tooth, denture base material, laboratory protocol and processing method has not yet been established. Extensive research enables the following recommendations for best practice to be made. Adopt practices that maximise the strength of the bond: select appropriate denture teeth; select base acrylic resin from the same manufacturer as the denture teeth; remove the glaze from ridgelaps of the denture teeth; apply monomer to the ridgelaps of the denture teeth before packing the base acrylic resin dough; use the manufacturers' recommended liquid/powder ratio; follow the manufacturers' recommended curing cycle; allow the flask to cool slowly and rest before deflasking. Adopt practices that avoid factors detrimental to bond strength: remove all traces of wax from the ridge laps of the denture teeth; remove all traces of mould seal from the ridgelaps of the denture teeth. It is evident that a number of factors are involved which may assist or prevent formation of an adequate bond, suggesting that attention to detail by the dental technician may be the most critical factor. PMID:24557385

  10. Propagation of ultrasonic guided waves in an acrylic plate as a cortical-bone-mimicking phantom

    NASA Astrophysics Data System (ADS)

    Lee, Kang Il; Choi, Bok Kyoung

    2014-12-01

    The present study aims to investigate the propagation of ultrasonic guided waves in an acrylic plate as a cortical-bone-mimicking phantom. The velocities of the guided waves in a 5-mm-thick acrylic plate were measured by using the axial transmission technique. A pure A0 Lamb mode could be successfully launched in the 5-mm-thick acrylic plate through a time reversal process of Lamb waves, consistent with the fact that the time reversal process can automatically compensate for the dispersive nature of Lamb waves. The experimental velocities of the slow guided wave (SGW) and the time-reversed Lamb wave were found to be in reasonable agreement with the theoretical group velocity of the A0 Lamb mode, suggesting that both the SGW and the time-reversed Lamb wave excited in the 5-mm-thick acrylic plate correspond to the A0 Lamb mode. These results suggest that the time reversal process of Lamb waves can be usefully applied to noninvasive characterization of long cortical bones.

  11. Transcatheter Embolization of a Large Symptomatic Pelvic Arteriovenous Malformation with Glubran 2 Acrylic Glue

    SciTech Connect

    Gandini, R.; Angelopoulos, G. Konda, D.; Messina, M.; Chiocchi, M.; Perretta, T.; Simonetti, G.

    2008-09-15

    A young patient affected by a pelvic arteriovenous malformation (pAVM) with recurrent episodes of hematuria following exercise, underwent transcatheter embolization using Glubran 2 acrylic glue (GEM, Viareggio, Italy). All branches of the pAVM were successfully occluded. The patient showed prompt resolution of symptoms and persistent occlusion of the pAVM at the 6 month follow-up.

  12. Delamination of layered double hydroxides in polar monomers: new LDH-acrylate nanocomposites.

    PubMed

    O'Leary, Shane; O'Hare, Dermot; Seeley, Gordon

    2002-07-21

    The layered double hydroxide Mg2Al(OH)6(C12H25SO4) was delaminated to give high levels of inclusion in acrylate monomers; subsequent polymerisation of the monomers containing the LDH dispersion gave polyacrylates with the inorganic component still in the delaminated form. PMID:12189866

  13. 40 CFR 721.338 - Salt of an acrylate copolymer (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.338 Salt of an acrylate copolymer (generic). (a) Chemical substance and significant new uses... (PMNs P-00-0333 and P-00-0334) are subject to reporting under this section for the significant new...

  14. 40 CFR 721.321 - Substituted acrylamides and acrylic acid copolymer (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.321 Substituted acrylamides and acrylic acid copolymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical...

  15. 40 CFR 721.465 - Alkoxylated alkylpolyol acrylates, adduct with alkylamine (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.465 Alkoxylated alkylpolyol acrylates, adduct with alkylamine (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The...

  16. 40 CFR 721.338 - Salt of an acrylate copolymer (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.338 Salt of an acrylate copolymer (generic). (a) Chemical substance and significant new uses... (PMNs P-00-0333 and P-00-0334) are subject to reporting under this section for the significant new...

  17. 40 CFR 721.321 - Substituted acrylamides and acrylic acid copolymer (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.321 Substituted acrylamides and acrylic acid copolymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical...

  18. 40 CFR 721.465 - Alkoxylated alkylpolyol acrylates, adduct with alkylamine (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.465 Alkoxylated alkylpolyol acrylates, adduct with alkylamine (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The...

  19. Acrylic cement creeps but does not allow much subsidence of femoral stems.

    PubMed

    Verdonschot, N; Huiskes, R

    1997-07-01

    It has been suggested that the endurance of cemented femoral reconstructions in total hip arthroplasty is affected by the creep of acrylic cement, but it is not known to what extent cement creeps under loading conditions in vivo, or how this affects load transfer. We have simulated the long-term creep properties of acrylic cement in finite-element models of femoral stem constructs and analysed their effects. We investigated whether subsidence rates measured in vivo could be explained by creep of acrylic cement, and if polished, unbonded, stems accommodated creep better than bonded stems. Our findings showed that polished prostheses subsided only about 50 microm as a result of cement creep. The long-term prosthetic subsidence rates caused by creep of acrylic cement are therefore very small and do not explain the excessive migration rates which have sometimes been reported. Cement creep did, however, relax cement stresses and create a more favourable stress distribution at the interfaces. These trends were found around both the bonded and unbonded stems. Our results did not confirm that polished, unbonded, stems accommodated creep better than bonded stems in terms of cement and interface stress patterns. PMID:9250762

  20. Prosthodontic self-treatment with acrylic resin super glue: a case report.

    PubMed

    Winkler, Sheldon; Wood, Robert; Facchiano, Anne M; Boberick, Kenneth G; Patel, Amita R

    2006-01-01

    A case history is presented of a patient who fabricated 3 prostheses from autopolymerizing acrylic resin intended for fingernail augmentation and then cemented them into her mouth with super glue. Patients must be warned not to attempt self-treatment for esthetics with self-fabricated prostheses because severe adverse and irreversible hard and soft tissue reactions may occur. PMID:16836177

  1. Assessment of the flexural strength of two heat-curing acrylic resins for artificial eyes.

    PubMed

    Fernandes, Aline Ursula Rocha; Portugal, Aline; Veloso, Letícia Rocha; Goiato, Marcelo Coelho; Santos, Daniela Micheline dos

    2009-01-01

    Prosthetic eyes are artificial substitutes for the eyeball, made of heat-curing acrylic resin, serving to improve the esthetic appearance of the mutilated patient and his/her inclusion in society. The aim of this study was to assess the flexural strength of two heat-curing acrylic resins used for manufacturing prosthetic eyes. Thirty-six specimens measuring 64 x 10 x 3.3 mm were obtained and divided into four groups: acrylic resin for artificial sclera N1 (Artigos Odontológicos Clássico, São Paulo, SP, Brazil), heat-cure water technique (GI) and microwave-cured (GII); colorless acrylic resin for prosthetic eyes (Artigos Odontológicos Clássico, São Paulo, SP, Brazil), heat-cure water technique (GIII) and microwave-cured (GIV). Mechanical tests using three point loads were performed in a test machine (EMIC, São José dos Pinhais, PR, Brazil). The analysis of variance and the Tukey test were used to identify significant differences (p < 0.01). Groups GII and GIV presented, respectively, the highest (98.70 +/- 11.90 MPa) and lowest means (71.07 +/- 8.93 MPa), with a statistically significant difference. The cure method used for the prosthetic eye resins did not interfere in their flexural strength. It was concluded that all the resins assessed presented sufficient flexural strength values to be recommended for the manufacture of prosthetic eyes. PMID:19893960

  2. Do flexible acrylic resin lingual flanges improve retention of mandibular complete dentures?

    PubMed Central

    Ahmed Elmorsy, Ayman Elmorsy; Ahmed Ibraheem, Eman Mostafa; Ela, Alaa Aboul; Fahmy, Ahmed; Nassani, Mohammad Zakaria

    2015-01-01

    Objectives: The aim of this study was to compare the retention of conventional mandibular complete dentures with that of mandibular complete dentures having lingual flanges constructed with flexible acrylic resin “Versacryl.” Materials and Methods: The study sample comprised 10 completely edentulous patients. Each patient received one maxillary complete denture and two mandibular complete dentures. One mandibular denture was made of conventional heat-cured acrylic resin and the other had its lingual flanges made of flexible acrylic resin Versacryl. Digital force-meter was used to measure retention of mandibular dentures at delivery and at 2 weeks and 45 days following denture insertion. Results: The statistical analysis showed that at baseline and follow-up appointments, retention of mandibular complete dentures with flexible lingual flanges was significantly greater than retention of conventional mandibular dentures (P < 0.05). In both types of mandibular dentures, retention of dentures increased significantly over the follow-up period (P < 0.05). Conclusions: The use of flexible acrylic resin lingual flanges in the construction of mandibular complete dentures improved denture retention. PMID:26539387

  3. Radiation grafting of acrylic and methacrylic acid to cellulose fibers to impart high water sorbency

    SciTech Connect

    Zahran, A.H.; Williams, J.L.; Stannett, V.T.

    1980-04-01

    Acrylic and methacrylic acids have been directly grafted to rayon and cotton using the preirradiation technique with /sup 60/ Co gamma rays. The rate of grafting increased with increasing temperature and monomer concentration, as did the final degree of grafting. The amount and rate of grafting also increased with the total irradiation dose but tended to level off at higher doses, in agreement with the leveling off of the radical content reported previously. Methacrylic acid grafted more and faster than acrylic acid to both rayon and cotton. Methacrylic acid grafted more with rayon than cotton, but acrylic acid gave somewhat similar yields with both fibers. The water abosrbency of the grafted fibers depended strongly on their posttreatment. Decrystallizing with 70% zinc chloride or with hot sodium hydroxidy developed supersorbency. The two treatments in succession, respectively, gave the highest values. Metacrylic acid brought about less sorbency than the corrsponding acrylic acid grafts. Useful levels of grafting and supersorbency could be readily and practically achieved by the methods described.

  4. 21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... methacrylate polymers. 177.2000 Section 177.2000 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.2000 Vinylidene chloride/methyl acrylate/methyl methacrylate polymers. The vinylidene chloride/methyl...

  5. Synthesis and application of novel EB curable polyester urethane acrylate modified by linseed oil fatty acid

    NASA Astrophysics Data System (ADS)

    Jun, Li; Xuecheng, Ju; Min, Yi; Jinshan, Wei; Hongfei, Ha

    1999-06-01

    A novel polyester urethane acrylate resin modified by linseed oil fatty acid (LFA) was synthesized and EB curing coating was formulated in this work. When the coating cured by EB radiation on the timber, the cured coating was possessed of good performances.

  6. 40 CFR 721.10223 - Styrenyl surface treated manganese ferrite with acrylic ester polymer (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10223 Styrenyl surface treated manganese ferrite with acrylic ester polymer (generic). (a) Chemical substance and significant new...

  7. Effect of Nanoclay on Thermal Conductivity and Flexural Strength of Polymethyl Methacrylate Acrylic Resin

    PubMed Central

    Ghaffari, Tahereh; Barzegar, Ali; Hamedi Rad, Fahimeh; Moslehifard, Elnaz

    2016-01-01

    Statement of the Problem The mechanical and thermal properties of polymethyl methacrylate (PMMA) acrylic resin should be improved to counterweigh its structural deficiencies. Purpose The aim of this study was to compare the flexural strength and thermal conductivity of conventional acrylic resin and acrylic resin loaded with nanoclay. Materials and Method The methacrylate monomer containing the 0.5, 1 and 2 wt% of nanoclay was placed in an ultrasonic probe and mixed with the PMMA powder. Scanning electron microscopy was used to verify homogeneous distribution of particles. Twenty-four 20×20×200-mm cubic samples were prepared for flexural strength test; 18 samples containing nanoclay and 6 samples for the control group. Another 24 cylindrical samples of 38×25 mm were prepared for thermal conductivity test. One-way ANOVA was used for statistical analysis, followed by multiple-comparison test (Scheffé’s test). Statistical significance was set at p< 0.05. Results Increasing the concentration of nanoclay incorporated into the acrylic resin samples increased thermal conductivity but decreased flexural strength (p< 0.05). Conclusion Based on the results of this study, adding nanoclay particles to PMMA improved its thermal conductivity, while it had a negative effect on the flexural strength. PMID:27284557

  8. 21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... methacrylate polymers. 177.2000 Section 177.2000 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.2000 Vinylidene chloride/methyl acrylate/methyl methacrylate polymers. The vinylidene chloride/methyl...

  9. Transdermal thiol-acrylate polyethylene glycol hydrogel synthesis using near infrared light

    NASA Astrophysics Data System (ADS)

    Chung, Solchan; Lee, Hwangjae; Kim, Hyung-Seok; Kim, Min-Gon; Lee, Luke P.; Lee, Jae Young

    2016-07-01

    Light-induced polymerization has been widely applied for hydrogel synthesis, which conventionally involves the use of ultraviolet or visible light to activate a photoinitiator for polymerization. However, with these light sources, transdermal gelation is not efficient and feasible due to their substantial interactions with biological systems, and thus a high power is required. In this study, we used biocompatible and tissue-penetrating near infrared (NIR) light to remotely trigger a thiol-acrylate reaction for efficient in vivo gelation with good controllability. Our gelation system includes gold nanorods as a photothermal agent, a thermal initiator, diacrylate polyethylene glycol (PEG), and thiolated PEG. Irradiation with a low-power NIR laser (0.3 W cm-2) could induce gelation via a mixed-mode reaction with a small increase in temperature (~5 °C) under the optimized conditions. We also achieved successful transdermal gelation via the NIR-assisted photothermal thiol-acryl reactions. This new type of NIR-assisted thiol-acrylate polymerization provides new opportunities for in situ hydrogel formation for injectable hydrogels and delivery of drugs/cells for various biomedical applications.Light-induced polymerization has been widely applied for hydrogel synthesis, which conventionally involves the use of ultraviolet or visible light to activate a photoinitiator for polymerization. However, with these light sources, transdermal gelation is not efficient and feasible due to their substantial interactions with biological systems, and thus a high power is required. In this study, we used biocompatible and tissue-penetrating near infrared (NIR) light to remotely trigger a thiol-acrylate reaction for efficient in vivo gelation with good controllability. Our gelation system includes gold nanorods as a photothermal agent, a thermal initiator, diacrylate polyethylene glycol (PEG), and thiolated PEG. Irradiation with a low-power NIR laser (0.3 W cm-2) could induce gelation

  10. The effect of flexible acrylic resin on masticatory muscle activity in implant-supported mandibular overdentures: a controlled clinical trial

    PubMed Central

    Ibraheem, Eman Mostafa Ahmed; Nassani, Mohammad Zakaria

    2016-01-01

    Background It is not yet clear from the current literature to what extent masticatory muscle activity is affected by the use of flexible acrylic resin in the construction of implant-supported mandibular overdentures. Objective To compare masticatory muscle activity between patients who were provided with implant-supported mandibular overdentures constructed from flexible acrylic resin and those who were provided with implant-supported mandibular overdentures constructed from heat-cured conventional acrylic resin. Methods In this clinical trial, 12 completely edentulous patients were selected and randomly allocated into two equal treatment groups. Each patient in Group 1 received two implants to support a mandibular overdenture made of conventional acrylic resin. In Group 2, the patients received two implants to support mandibular overdentures constructed from “Versacryl” flexible acrylic resin. The maxillary edentulous arch for patients in both groups was restored by conventional complete dentures. For all patients, masseter and temporalis muscle activity was evaluated using surface electromyography (sEMG). Results The results showed a significant decrease in masticatory muscle activity among patients with implant-supported mandibular overdentures constructed from flexible acrylic resin. Conclusion The use of “Versacryl” flexible acrylic resin in the construction of implant-supported mandibular overdentures resulted in decreased masticatory muscle activity. PMID:26955445

  11. Evaluation of Bond Strength of Acrylic Teeth to Denture Base using Different Polymerization Techniques: A Comparative Study

    PubMed Central

    Yadav, Naveen S; Somkuwar, Surabhi; Mishra, Sunil Kumar; Hazari, Puja; Chitumalla, Rajkiran; Pandey, Shilpi K

    2015-01-01

    Background: Acrylic teeth have long been used in the treatment of a complete denture. One of the primary advantages of acrylic teeth is their ability to adhesively bond to the denture base resins. Although the bonding seems satisfactory, however, bond failures at the acrylic teeth and denture base resin interface are still a common clinical problem in prosthodontics. The purpose of this study was to evaluate the bond strength of acrylic teeth to denture base using different polymerizing techniques. Materials and Methods: Acrylic resin teeth were bonded to heat cure acrylic resin and were polymerized by conventional water bath and microwave energy. The samples are then retrieved from the flask; trimmed and polished. The samples were then subjected to tensile forces till failure by using the Instron Universal testing machine. The machine used a direct pull on the incisal portion of the lingual surface in a labial direction at a height above the denture base resin bar with a crosshead speed of 0.5 mm/min. Results: In the present study, it was found that conventionally cured specimens exhibited higher bond strength than microwave cured specimens and majority of fractures occur within the body of the tooth. It was found that debonding occurs within the body of the tooth rather than tooth acrylic interface, so there is no need of surface treatment of ridge lap surface. Conclusion: Conventionally cured specimens possess statistically higher bond strength than microwave cured specimens. PMID:26225106

  12. Effect of tyrosol on adhesion of Candida albicans and Candida glabrata to acrylic surfaces.

    PubMed

    Monteiro, Douglas Roberto; Feresin, Leonardo Perina; Arias, Laís Salomão; Barão, Valentim Adelino Ricardo; Barbosa, Debora Barros; Delbem, Alberto Carlos Botazzo

    2015-09-01

    The prevention of adhesion of Candida cells to acrylic surfaces can be regarded as an alternative to prevent denture stomatitis. The use of quorum sensing molecules, such as tyrosol, could potentially interfere with the adhesion process. Therefore, the aim of this study was to assess the effect of tyrosol on adhesion of single and mixed cultures of Candida albicans and Candida glabrata to acrylic resin surfaces. Tyrosol was diluted in each yeast inoculum (10(7) cells/ml in artificial saliva) at 25, 50, 100, and 200 mM. Then, each dilution was added to wells of 24-well plates containing the acrylic specimens, and the plates were incubated at 37°C for 2 h. After, the effect of tyrosol was determined by total biomass quantification, metabolic activity of the cells and colony-forming unit counting. Chlorhexidine gluconate (CHG) was used as a positive control. Data were analyzed using analysis of variance (ANOVA) and the Holm-Sidak post hoc test (α = 0.05). The results of total biomass quantification and metabolic activity revealed that the tyrosol promoted significant reductions (ranging from 22.32 to 86.16%) on single C. albicans and mixed cultures. Moreover, tyrosol at 200 mM and CHG significantly reduced (p < 0.05) the number of adhered cells to the acrylic surface for single and mixed cultures of both species, with reductions ranging from 1.74 to 3.64-log10. In conclusion, tyrosol has an inhibitory effect on Candida adhesion to acrylic resin, and further investigations are warranted to clarify its potential against Candida infections. PMID:26162470

  13. Hydrophilic Acrylic versus PMMA Intraocular Lens Implantation in Pediatric Cataract Surgery

    PubMed Central

    Panahi-Bazaz, Mahmoud-Reza; Zamani, Mitra; Abazar, Bijan

    2009-01-01

    Purpose To compare primary implantation of foldable hydrophilic acrylic with polymethylmethacrylate (PMMA) intraocular lenses (IOLs) in pediatric cataract surgery in terms of short-term complications and visual outcomes. Methods This randomized clinical trial included 40 eyes of 31 consecutive pediatric patients aged 1 to 6 years with unilateral or bilateral congenital cataracts undergoing cataract surgery with primary IOL implantation. Two types of IOLs including foldable hydrophilic acrylic and rigid PMMA were randomly implanted in the capsular bag during surgery. Primary posterior capsulotomy and anterior vitrectomy were performed in all eyes. Patients were followed for at least 1 year. Intra- and postoperative complications, visual outcomes and refractive errors were compared between the study groups. Results Mean age was 3.2±1.8 years in the hydrophilic acrylic group and 3.7±1.3 years in the PMMA group. Mean follow-up period was 19.6±5 (12–29) months. No intraoperative complication occurred in any group. Postoperative uveitis was seen in 2 (10%) eyes in the acrylic group versus 5 (25%) eyes in the PMMA group (P=0.40). Other postoperative complications including pigment deposition (30%), iridocorneal adhesions (10%) and posterior synechiae formation (10%), were seen only in the PMMA group. The visual axis remained completely clear and visual outcomes were generally favorable and comparable in the study groups. Conclusion In pediatric eyes undergoing lensectomy with primary posterior capsulotomy and anterior vitrectomy, hydrophilic acrylic IOLs are comparable to PMMA IOLs in terms of biocompatibility and visual axis clarity, and seem to entail less frequent postoperative complications. PMID:23198075

  14. Influence of ozone and paracetic acid disinfection on adhesion of resilient liners to acrylic resin

    PubMed Central

    2016-01-01

    PURPOSE The aim of this study was to evaluate the effect of paracetic acid (PAA) and ozone disinfection on the tensile bond strength (TBS) of silicone-based resilient liners to acrylic resins. MATERIALS AND METHODS One hundred and twenty dumbbell shaped heat-polymerized acrylic resins were prepared. From the mid segment of the specimens, 3 mm of acrylic were grinded off and separated parts were reattached by resilient liners. The specimens were divided into 2 control (control1, control7) and 4 test groups of PAA and ozone disinfection (PAA1, PAA7, ozone1 and ozone7; n=10). While control groups were immersed in distilled water for 10 min (control1) and 7 days (control7), test groups were subjected to PAA (16 g/L) or ozone rich water (4 mg/L) for 1 cycle (10 min for PAA and 60 min for ozone) per day for 7 days prior to tensile tests. Measurements of the TBS were analyzed using 3-way ANOVA and Tukey's HSD test. RESULTS Adhesive strength of Mollosil decreased significantly by application of ozone disinfection. PAA disinfection had no negative effect on the TBS values of Mollosil and Molloplast B to acrylic resin. Single application of ozone disinfection did not have any negative effect on TBS values of Molloplast B, but prolonged exposure to ozone decreased its adhesive strength. CONCLUSION The adhesion of resilient liners to acrylic was not adversely affected by PAA disinfection. Immersion in ozonated water significantly decreased TBS of Mollosil. Prolonged exposure to ozone negatively affects adhesion of Molloplast B to denture base materials. PMID:27555898

  15. Oleanolic acid acrylate elicits antidepressant-like effect mediated by 5-HT1A receptor

    PubMed Central

    Fajemiroye, James O.; Polepally, Prabhakar R.; Chaurasiya, Narayan D.; Tekwani, Babu L.; Zjawiony, Jordan K.; Costa, Elson A.

    2015-01-01

    The development of new drugs for the treatment of depression is strategic to achieving clinical needs of patients. This study evaluates antidepressant-like effect and neural mechanisms of four oleanolic acid derivatives i.e. acrylate (D1), methacrylate (D2), methyl fumarate (D3) and ethyl fumarate (D4). All derivatives were obtained by simple one-step esterification of oleanolic acid prior to pharmacological screening in the forced swimming (FS) and open field (OF) tests. Pharmacological tools like α-methyl-p-tyrosine (AMPT, catecholamine depletor), p-chlorophenylalanine (serotonin depletor), prazosin (PRAZ, selective α1-receptor antagonist), WAY-100635 (selective serotonin 5-HT1A receptor antagonist) as well as monoamine oxidase (MAO) and functional binding assays were conducted to investigate possible neural mechanisms. In the FS test, D1 showed the most promising antidepressant-like effect without eliciting locomotor incoordination. Unlike group of mice pretreated with AMPT 100 mg/kg, PCPA 100 mg/kg or PRAZ 1 mg/kg, the effect of D1 was attenuated by WAY-100635 0.3 mg/kg pretreatment. D1 demonstrated moderate inhibition of MAO-A (IC50 = 48.848 ± 1.935 μM), potency (pEC50 = 6.1 ± 0.1) and intrinsic activity (Emax = 26 ± 2.0%) on 5-HT1A receptor. In conclusion, our findings showed antidepressant-like effect of D1 and possible involvement of 5-HT1A receptor. PMID:26199018

  16. Preparation and application of sol-gel acrylate and methacrylate solid-phase microextraction fibres for gas chromatographic analysis of organoarsenic compounds.

    PubMed

    Popiel, Stanisław; Nawała, Jakub; Czupryński, Krzysztof

    2014-07-21

    Novel solid-phase microextraction (SPME) fibres containing methyl, ethyl, butyl acrylate and methacrylate were first prepared by a sol-gel technique and investigated for determination of selected organoarsenic compounds (lewisite, methyldichloroarsine, phenyldichloroarsine, diphenylchloroarsine and triphenylarsine) from water samples. The influence of sorption and desorption temperature and time for extraction efficiency were examined. The best new fibre coatings (methyl acrylate (MA), methyl methacrylate (MMA) and combination of methyl acrylate and methacrylate (MA/MMA)) for analysis of organoarsenic compounds were selected and compared with commercial fibres. The distribution coefficients Kfs were determined for the best novel fibres and for absorption commercial fibres. The highest Kfs value were obtained for MA/MMA and MMA fibres and were respectively 9458 and 6561 for lewisite and 6458 and 5884 for triphenylarsine. The limit of detection and quantification were determined for the three laboratory obtained fibres (MA, MMA and MA/MMA). LODs for tested fibres, at a signal-to-noise of 3, were 0.03-0.3 ng mL(-1). LOQs for selected coatings, at signal-to-noise of 10, were 0.1-0.8 ng mL(-1). The relative standard deviations (RSD) for all measurements were 4.3-6.5% (n=9) and relative errors were 2.5-5%. The laboratory obtained fibres were used for environmental analysis of pore water samples from the Baltic Sea. PMID:25000858

  17. Degradable thiol-acrylate hydrogels as tunable matrices for three-dimensional hepatic culture.

    PubMed

    Hao, Yiting; Lin, Chien-Chi

    2014-11-01

    A degradable poly(ethylene glycol)-diacrylate (PEGDA) hydrogel system was developed using simple macromer formulations and visible light initiated thiol-acrylate photopolymerization. In addition to PEGDA, other components in this gelation system include eosin-Y as a photo-sensitizer, bi-functional thiol (dithiothreitol, DTT) as a dual-purpose co-initiator and cross-linker, and N-vinylpyrrolidone (NVP) as a co-monomer. Gelation was achieved through a mixed-mode step-chain growth polymerization mechanism under bright visible light exposure. Increasing photo-sensitizer or NVP concentrations accelerated photo-crosslinking and increased final gel stiffness. Increasing bi-functional thiol content in the prepolymer solution only increased gel stiffness to some degree. As the concentration of thiol surpassed certain range, thiol-mediated chain-transfer events caused thiol-acrylate gels to form with lower degree of cross-linking. Pendant peptide, such as integrin ligand RGDS, was more effectively immobilized in the network via a thiol-acrylate reaction (using thiol-bearing peptide Ac-CRGDS. Underline indicates cross-linkable motif) than through homo-polymerization of acrylated peptide (e.g., acryl-RGDS). The incorporation of pendant peptide comes with the expense of a lower degree of gel cross-linking, which was rectified by increasing co-monomer NVP content. Without the use of any readily degradable macromer, these visible light initiated mixed-mode cross-linked hydrogels degraded hydrolytically due to the formation of thiol-ether-ester bonds following thiol-acrylate reactions. An exponential growth relationship was identified between the hydrolytic degradation rate and bifunctional thiol content in the prepolymer solution. Finally, we evaluated the cytocompatibility of these mixed-mode cross-linked degradable hydrogels using in situ encapsulation of hepatocellular carcinoma Huh7 cells. Encapsulated Huh7 cells remained alive and proliferated as time to form cell clusters

  18. Comparison of two different silane compounds used for improving adhesion between fibres and acrylic denture base material.

    PubMed

    Vallittu, P K

    1993-09-01

    This study was aimed at clarifying the effects of two different silane compounds on the adhesion between the different fibres and acrylic resin. The fibres used as reinforcement in the acrylic resin test specimens were glass, carbon and aramid fibres and the silane treated and untreated versions of each type of the fibres were tested. The fracture resistance of the test specimens were assessed and the fibres were studied by a scanning electron microscope (SEM) to establish the adhesion between the fibres and acrylic resin. The results showed that silanization of glass and aramid fibres enhances the adhesion between the fibres and acrylic resin. The findings were confirmed by the SEM photographs taken. The use of a scanning electron microscope proved to be useful for the investigation of the adhesive properties of the materials used. PMID:10412475

  19. Development of Periodic and Three-Dimensional Structures in Acrylic-Monomer Photopolymer Materials by Holographic Methods

    NASA Astrophysics Data System (ADS)

    Vorzobova, N. D.; Bulgakova, V. G.; Moskalenko, A. I.; Pavlovets, I. M.; Denisyuk, I. Yu.; Burunkova, Yu. É.

    2015-01-01

    We show the possibility and advantages of using photopolymer materials based on acrylic monomers and nanocomposites in holography. Holographic characteristics of these materials and conditions for forming periodic structures and three-dimensional elements in them are determined.

  20. Bond strength of acrylic teeth to denture base resin after various surface conditioning methods before and after thermocycling.

    PubMed

    Saavedra, Guilherme; Valandro, Luiz Felipe; Leite, Fabiola Pessoa Pereira; Amaral, Regina; Ozcan, Mutlu; Bottino, Marco A; Kimpara, Estevão T

    2007-01-01

    This study aimed to evaluate the durability of adhesion between acrylic teeth and denture base acrylic resin. The base surfaces of 24 acrylic teeth were flatted and submitted to 4 surface treatment methods: SM1 (control): No SM; SM2: application of a methyl methacrylate-based bonding agent (Vitacol); SM3: air abrasion with 30-microm silicone oxide plus silane; SM4: SM3 plus SM2. A heat-polymerized acrylic resin was applied to the teeth. Thereafter, bar specimens were produced for the microtensile test at dry and thermocyled conditions (60 days water storage followed by 12,000 cycles). The results showed that bond strength was significantly affected by the SM (P < .0001) (SM4 = SM2 > SM3 > SM1) and storage regimens (P < .0001) (dry > thermocycled). The methyl methacrylate-based adhesive showed the highest bond strength. PMID:17455445

  1. Effects of water on starch-g-polystyrene and starch-g-poly(methyl acrylate) extrudates. [Gamma radiation

    SciTech Connect

    Henderson, A.M.; Rudin, A.

    1982-11-01

    Polystyrene and poly(methyl acrylate) were grafted onto wheat starch by gamma radiation and chemical initiation, respectively. The respective percent add-on values were 46 and 45; 68% of the polystyrene formed was grafted to starch, and corresponding proportion of poly(methyl acrylate) was 41%. The molecular weight distributions of the homopolymer and graft portions were characterized, and extrusion conditions were established for production of ribbon samples of starch-g-PS and starch-g-PMA. Both copolymer types were considerably weakened by soaking in water, and this effect was more immediate and drastic for starch-g-poly(methyl acrylate). Both graft copolymers regained their original tensile strengths on drying, but the poly(methyl acrylate) specimens did not recover their original unswollen dimensions and retained high breaking elongations characteristic of soaked specimens. Tensile and dynamic mechanical properties of extruded and molded samples of both graft polymers are reported, and plasticizing effects of water are summarized.

  2. Real-time monitoring of graphene oxide reduction in acrylic printable composite inks

    NASA Astrophysics Data System (ADS)

    Porro, S.; Giardi, R.; Chiolerio, A.

    2014-06-01

    This work reports the electrical characterization of a water-based graphene oxide/acrylic composite material, which was directly inkjet printed to fabricate dissipative patterns. The graphene oxide filler, which is strongly hydrophilic due to its heavily oxygenated surface and can be readily dispersed in water, was reduced by UV irradiation during photo-curing of the polymeric matrix. The concurrent polymerization of the acrylic matrix and reduction of graphene oxide filler was demonstrated by real-time resistance measurements during UV light irradiation. The presence of graphene filler allowed decreasing the resistance of the pure polymeric matrix by nearly five orders of magnitude. This was explained by the fact that clusters of reduced graphene oxide inside the polymer matrix act as preferential pathways for the mobility of charge carriers, thus leading to an overall decrease of the material's resistance.

  3. Flexural strength of acrylic resin denture bases processed by two different methods.

    PubMed

    Gharechahi, Jafar; Asadzadeh, Nafiseh; Shahabian, Foad; Gharechahi, Maryam

    2014-01-01

    Background and aims. The aim of this study was to compare flexural strength of specimens processed by conventional and injection-molding techniques. Materials and methods. Conventional pressure-packed PMMA was used for conventional pressure-packed and injection-molded PMMA was used for injection-molding techniques. After processing, 15 specimens were stored in distilled water at room temperature until measured. Three-point flexural strength test was carried out. Statistical analysis was carried out by SPSS using t-test. Statistical significance was defined at P<0.05. Results. Flexural strength of injection-polymerized acrylic resin specimens was higher than that of the conventional method (P=0.006). This difference was statistically significant (P=0.006). Conclusion. Within the limitations of this study, flexural strength of acrylic resin specimens was influenced by the molding technique. PMID:25346833

  4. Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

    NASA Astrophysics Data System (ADS)

    Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H.

    2015-05-01

    Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers' perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied.

  5. Flexural Strength of Acrylic Resin Denture Bases Processed by Two Different Methods

    PubMed Central

    Gharechahi, Jafar; Asadzadeh, Nafiseh; Shahabian, Foad; Gharechahi, Maryam

    2014-01-01

    Background and aims. The aim of this study was to compare flexural strength of specimens processed by conventional and injection-molding techniques. Materials and methods. Conventional pressure-packed PMMA was used for conventional pressure-packed and injection-molded PMMA was used for injection-molding techniques. After processing, 15 specimens were stored in distilled water at room temperature until measured. Three-point flexural strength test was carried out. Statistical analysis was carried out by SPSS using t-test. Statistical significance was defined at P<0.05. Results. Flexural strength of injection-polymerized acrylic resin specimens was higher than that of the conventional method (P=0.006). This difference was statistically significant (P=0.006). Conclusion. Within the limitations of this study, flexural strength of acrylic resin specimens was influenced by the molding technique. PMID:25346833

  6. Modification of silicon nitride slip properties by poly(acrylic acid)

    SciTech Connect

    Hackley, V.A.; Maglhan, S.G.

    1996-06-01

    Acrylic-acid based polyelectrolytes are used for dispersion and rheology control of ceramic powder slips. This study focuses on the Si{sub 3}N4/H{sub 2}O/poly(acrylic acid) (PAA) system, with the goal of improving our basic understanding of the mechanisms which may significantly affect slip properties during processing. A variety of experimental techniques were employed, including potentiometric titration, electroacoustic analysis, adsorption isotherms, and controlled-stress rheology. The slips exhibited complex behavior over a wide range of conditions in which solids concentration, PAA molecular weight and concentration, and pH were varied. Polymer charge and conformation were found to have significant impact on the flow properties. Pseudoplastic behavior was attributed to the presence of free polymer. The flow properties were also found to be highly pH dependent.

  7. (E)-Methyl 3-(10-bromo­anthracen-9-yl)acrylate

    PubMed Central

    Bugenhagen, Bernhard; Al Jasem, Yosef; Hindawi, Bassam al; Al Rawashdeh, Nathir; Thiemann, Thies

    2013-01-01

    In the title mol­ecule, C18H13BrO2, the anthracene unit forms an angle of 46.91 (2)° with the mean plane of the methyl acrylate moiety. In the crystal, the mol­ecules arrange themselves into strands parallel to [010] and, due to the crystal symmetry, there are eight strands crossing the unit cell. In each strand, mol­ecules form short C—H⋯O and C—H⋯π contacts and have their anthracene groups parallel to each other. Neighboring strands, related by a c-glide operation, are connected via C—H⋯O inter­actions and form a layer parallel to (100). The arrangement of the acrylate and anthracene groups in the crystal do not allow for [2 + 2] or [4 + 4] cyclo­addition. PMID:24046689

  8. Preparation of poly(acrylic acid) particles by dispersion polymerization in an ionic liquid.

    PubMed

    Minami, Hideto; Kimura, Akira; Kinoshita, Keigo; Okubo, Masayoshi

    2010-05-01

    Poly(acrylic acid) (PAA) particles were successfully prepared by dispersion polymerization of acrylic acid in ionic liquid, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoro-methanesulfonyl)amide ([DEME][TFSA]) at 70 degrees C with low hydrolysis grade (35.4%) poly(vinyl alcohol) as stabilizer. Interestingly, the PAA particles were easily extracted as particle state with water. Thus, the PAA particles had a cross-linked structure during the polymerization without cross-linker. Moreover, it was also noted that the cross-linking density of the PAA particles could be controlled by thermal treatment at various temperatures in [DEME][TFSA] utilizing the advantages of nonvolatility and high thermal stability of the ionic liquid. PMID:20043688

  9. Thermoresponsive fibers containing n-stearyl acrylate groups for shape memory effect

    NASA Astrophysics Data System (ADS)

    Chen, L.; Yu, X.; Feng, X.; Han, Y. L.; Liu, M.; Lin, T. X.

    2007-07-01

    A novel kind of thermoresponsive shape memory fiber was prepared by mixing the P(SA-co-AA) copolymers of stearyl acrylate (SA), and acrylic acid (AA), with PVA polyvinyl alcohol through chemically crosslinking after spinning. The molecular structure, thermomechanical properties and shape memory behaviors were investigated. It was found that the mixed P(SA-co-AA)/PVA fibers had crystalline structures and showed a dramatic change in Young's modulus at melting temperature (Tm) due to the reversible order-disorder transition. The mixed P(SA-co-AA)/PVA fibers also showed a good shape memory effect, through which the deformed fibers could recover to their original shapes and sizes within 40 seconds after they were heated above their Tm again.

  10. Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

    SciTech Connect

    Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H.

    2015-05-22

    Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers’ perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied.

  11. Fabrication and electrical properties of metal-coated acrylate rubber microspheres by electroless plating

    NASA Astrophysics Data System (ADS)

    Gao, D. L.; Zhan, M. S.

    2009-01-01

    Electroless copper plating on micron-scale acrylate rubber (ACM) microspheres was studied. The core-shell structured Cu-coated ACM microspheres with high conductivity and low density were fabricated by introducing a reaction control method. Via multi-times activating treatment, the acrylate rubber (ACM) microspheres were implanted with more Ag catalytic active centers on the surfaces to promote the formation of coatings. The surface-coating structures and the electrical properties of Cu-coated ACM microspheres were investigated. It was found that the Cu-coated ACM microspheres were a kind of elastic particles. The different coating structures could be produced by controlling the extent of plating reaction. The coated microspheres with different coating structures were conductive, and their volume resistivities decreased remarkably with the increasing of applied pressure and varied with the temperature according to their surface coating structures.

  12. Preparation of poly (styrene)-b-poly (acrylic acid)/γ-Fe 2O 3 composites

    NASA Astrophysics Data System (ADS)

    Zhang, L. D.; Liu, W. L.; Xiao, C. L.; Yao, J. S.; Fan, Z. P.; Sun, X. L.; Zhang, X.; Wang, L.; Wang, X. Q.

    2011-12-01

    The use of a block copolymer, poly (styrene)-b-poly (acrylic acid) (PS-b-PAA) to prepare a magnetic nanocomposite was investigated. Poly (styrene)-poly (t-butyl acrylate) block copolymer, being synthesized by atom transfer radical polymerization, was hydrolyzed with hydrochloric acid for obtaining PS-b-PAA. The obtained PS-b-PAA was then compounded with the modified γ-Fe2O3, and subsequently the magnetic nanocomposite was achieved. The products were characterized by 1H NMR, FTIR, gel permeation chromatography, thermogravimetric analysis, transmission electron microscopy and vibrating sample magnetometer. The results showed that the nanocomposites exhibited soft magnetism, with the mean diameter of 100 nm approximately.

  13. Preparation of metal adsorbent from poly(methyl acrylate)-grafted-cassava starch via gamma irradiation

    NASA Astrophysics Data System (ADS)

    Suwanmala, Phiriyatorn; Hemvichian, Kasinee; Hoshina, Hiroyuki; Srinuttrakul, Wannee; Seko, Noriaki

    2012-08-01

    Metal adsorbent containing hydroxamic acid groups was successfully synthesized by radiation-induced graft copolymerization of methyl acrylate (MA) onto cassava starch. The optimum conditions for grafting were studied in terms of % degree of grafting (Dg). Conversion of the ester groups present in poly(methyl acrylate)-grafted-cassava starch copolymer into hydroxamic acid was carried out by treatment with hydroxylamine (HA) in the presence of alkaline solution. The maximum percentage conversion of the ester groups of the grafted copolymer, % Dg=191 (7.63 mmol/g of MA), into the hydroxamic groups was 70% (5.35 mmol/g of MA) at the optimum condition. The adsorbent of 191%Dg had total adsorption capacities of 2.6, 1.46, 1.36, 1.15 and 1.6 mmol/g-adsorbent for Cd2+, Al3+, UO22+, V5+ and Pb2+, respectively, in the batch mode adsorption.

  14. Relationship between cell surface composition of Candida albicans and adherence to acrylic after growth on different carbon sources.

    PubMed Central

    McCourtie, J; Douglas, L J

    1981-01-01

    The adherence of Candida albicans to acrylic was measured in vitro after growth of the yeast to stationary phase in defined medium containing glucose, sucrose, galactose, fructose, or maltose as the carbon source. In each case, yeast adherence was proportional to the concentration of sugar in the growth medium, but equimolar concentrations of different sugars promoted adherence to different extents. In vitro adherence was further increased by the addition of divalent cations to assay mixtures but was inhibited when saliva-treated acrylic strips were used or when yeasts were suspended in mixed saliva during the assay. The rate of spheroplast formation of yeasts grown in media containing a 500 mM concentration of the different sugars correlated well with the relative adherence of the cells to acrylic. Galactose-grown yeasts were most resistant to spheroplast formation with Zymolyase-5000 and most adherent to acrylic, whereas fructose-grown organisms were least resistant to spheroplast formation and least adherent to acrylic. These results indicate that when grown to stationary phase in media containing high concentrations of certain sugars, C. albicans undergoes a change in cell surface composition which facilitates its adherence to acrylic surfaces. Electron microscopy of yeasts harvested from such media revealed the presence of an additional surface layer which may be responsible for this enhanced adherence. Images PMID:7019091

  15. Effect of water-aging on the antimicrobial activities of an ORMOSIL-containing orthodontic acrylic resin.

    PubMed

    Gong, Shi-Qiang; Epasinghe, D Jeevanie; Zhou, Bin; Niu, Li-Na; Kimmerling, Kirk A; Rueggeberg, Frederick A; Yiu, Cynthia K Y; Mao, Jing; Pashley, David H; Tay, Franklin R

    2013-06-01

    Quaternary ammonium methacryloxy silicate (QAMS), an organically modified silicate (ORMOSIL) functionalized with polymerizable methacrylate groups and an antimicrobial agent with a long lipophilic alkyl chain quaternary ammonium group, was synthesized through a silane-based sol-gel route. By dissolving QAMS in methyl methacrylate monomer, this ORMOSIL molecule was incorporated into an auto-polymerizing, powder/liquid orthodontic acrylic resin system, yielding QAMS-containing poly(methyl methacrylate). The QAMS-containing acrylic resin showed a predominant contact-killing effect on Streptococcus mutans (ATCC 35668) and Actinomyces naeslundii (ATCC 12104) biofilms, while inhibiting adhesion of Candida albicans (ATCC 90028) on the acrylic surface. The antimicrobial activities of QAMS-containing acrylic resin were maintained after a 3month water-aging period. Bromophenol blue assay showed minimal leaching of quaternary ammonium species when an appropriate amount of QAMS (<4wt.%) was incorporated into the acrylic resin. The results suggest that QAMS is predominantly co-polymerized with the poly(methyl methacrylate) network, and only a minuscule amount of free QAMS molecules is present within the polymer network after water-aging. Acrylic resin with persistent antimicrobial activities represents a promising method for preventing bacteria- and fungus-induced stomatitis, an infectious disease commonly associated with the wearing of removable orthodontic appliances. PMID:23485857

  16. Effect of water-aging on the antimicrobial activities of an ORMOSIL-containing orthodontic acrylic resin

    PubMed Central

    Gong, Shi-qiang; Epasinghe, D. Jeevanie; Zhou, Bin; Niu, Li-na; Kimmerling, Kirk A.; Rueggeberg, Frederick A.; Yiu, Cynthia K.Y.; Mao, Jing; Pashley, David H.; Tay, Franklin R.

    2013-01-01

    Quaternary ammonium methacryloxy silicate (QAMS), an organically modified silicate (ORMOSIL) functionalized with polymerizable methacrylate groups and an antimicrobial agent with a long lipophilic alkyl chain quaternary ammonium group, was synthesized through a silane-based sol–gel route. By dissolving QAMS in methyl methacrylate monomer, this ORMOSIL molecule was incorporated into an auto-polymerizing, powder/liquid orthodontic acrylic resin system, yielding QAMS-containing poly (methyl methacrylate). The QAMS-containing acrylic resin showed a predominant contact-killing effect on Streptococcus mutans (ATCC 35668) and Actinomyces naeslundii (ATCC 12104) biofilms, while inhibiting adhesion of Candida albicans (ATCC 90028) on the acrylic surface. The antimicrobial activities of QAMS-containing acrylic resin were maintained after a 3 month water-aging period. Bromophenol blue assay showed minimal leaching of quaternary ammonium species when an appropriate amount of QAMS (<4 wt.%) was incorporated into the acrylic resin. The results suggest that QAMS is predominantly co-polymerized with the poly(methyl methacrylate) network, and only a minuscule amount of free QAMS molecules is present within the polymer network after water-aging. Acrylic resin with persistent antimicrobial activities represents a promising method for preventing bacteria- and fungus-induced stomatitis, an infectious disease commonly associated with the wearing of removable orthodontic appliances. PMID:23485857

  17. Ultrafine metal particles immobilized on styrene/acrylic acid copolymer particles

    SciTech Connect

    Tamai, Hisashi; Hamamoto, Shiro; Nishiyama, Fumitaka; Yasuda, Hajime

    1995-04-01

    Ultrafine metal particles immobilized on styrene/acrylic acid copolymer fine particles were produced by reducing the copolymer particles-metal ion complexes or refluxing an ethanol solution of metal ions in the presence of copolymer particles. The size of metal particles formed by reduction of the complex is smaller than that by reflux of the metal ion solution and depends on the amount of metal ions immobilized.

  18. Antifungal Effect of Zataria multiflora Essence on Experimentally Contaminated Acryl Resin Plates With Candida albicans

    PubMed Central

    Jafari, Abbas Ali; Falah Tafti, Abbas; Hoseiny, Seyed Mehdi; Kazemi, Abdolhossein

    2015-01-01

    Background: Adherence and colonization of Candida species particularly C. albicans on denture surfaces, forms a microbial biofilm, which may result denture stomatitis in complete denture users. Objectives: The purpose of the present study was to evaluate the antifungal effect Zataria multiflora essence in removing of Candida albicans biofilms on experimentally contaminated resin acryl plates. Materials and Methods: In the present experimental study, 160 resin acrylic plates (10 × 10 × 1 mm) were contaminated by immersion in 1 × 103 C. albicans suspension for 24 hours to prepare experimental Candida biofilms. The total number of Candida cells, which adhered to 20 randomly selected acryl resin plates was determined as the Candia load before cleaning. The remaining 140 plates were divided to seven groups of 20 and immersed in five concentrations of Zataria multiflora essence from 50 to 3.125 mg/mL as test, 100000 IU nystatin as the positive and sterile physiologic serum as the negative control. The remaining Candida cells on each acryl plate were also enumerated and data were analyzed using the SPSS 16 software with Kruskal-Wallis and Wilcoxon tests. Results: Zataria essence at concentrations of 50 and 25 mg/mL removed 100% of attached Candida cells similar to nystatine (MFC), while weaker Zataria essence solutions cleaned 88%, 60.5% and 44.7% of attached Candida cells. Kruskal-wallis test showed a statistically significant difference between all test groups (P = 0.0001). In this study 12.5 mg/mL concentration of Zataria multiflora was considered as the minimum inhibitory concentration (MIC90). Conclusions: Zataria essence, at concentrations of 50 and 25 mg/mL, effectively removed Candida cells that had adhered to the denture surface, similar to the level of removal observed for 100000 IU nystatin. PMID:25763273

  19. Inhibitory Effect of Alpha-Mangostin on Adhesion of Candida albicans to Denture Acrylic

    PubMed Central

    Kaomongkolgit, Ruchadaporn; Jamdee, Kusuma

    2015-01-01

    Objective: Candida-associated denture stomatitis is a very common disease affecting denture wearers. It is characterized by the presence of yeast biofilm on the denture, primarily associated with C. albicans. The investigation of agents that can reduce C. albicans adhesion may represent a significant advancement in the prevention and treatment of this disease. This study aims to investigate the effect of alpha-mangostin on the in vitro adhesion of C. albicans to denture acrylic and germ tube formation by C. albicans and to compare its activity with clotrimazole which is a topical antifungal agent commonly used for the treatment of Candida-associated denture stomatitis. Materials and Methodology: Alpha-mangostin was extracted by thin layer chromatography. The effect of alpha-mangostin on adhesion of C. albicans to denture acrylic was determined by using a colorimetric tetrazolium assay and germ tube formation by C. albicans was determined by using the counting chamber. Results: A significant reduction of C. albicans adhesion to denture acrylic was evident after exposure to 2,000 µg/ml of alpha-mangostin for only 15 min. In addition, the 2,000 µg/ml of the alpha-mangostin-treated C. albicans had a reduced ability for germ tube formation. These inhibitory effects of alpha-mangostin were as effective as clotrimazole. Conclusion: Alpha-mangostin has antifungal property against C. albicans by inhibiting the adhesion to denture acrylic and germ tube formation in vitro. These results suggest the potential application of alpha-mangostin as a topical medication or a natural oral hygiene product for treatment of Candida-associated denture stomatitis. PMID:26962371

  20. Characterization and bacterial anti-adherent effect on modified PMMA denture acrylic resin containing platinum nanoparticles

    PubMed Central

    2014-01-01

    PURPOSE This study characterized the synthesis of a modified PMMA (Polymethyl methacrylate) denture acrylic loading platinum nanoparticles (PtN) and assessed its bacterial inhibitory efficacy to produce novel antimicrobial denture base material. MATERIALS AND METHODS Polymerized PMMA denture acrylic disc (20 mm × 2 mm) specimens containing 0 (control), 10, 50, 100 and 200 mg/L of PtN were fabricated respectively. The obtained platinum-PMMA nanocomposite (PtNC) was characterized by TEM (transmission electron microscopy), SEM/EDX (scanning electron microscope/energy dispersive X-ray spectroscopy), thermogravimetric and atomic absorption spectrophotometer analysis. In antimicrobial assay, specimens were placed on the cell culture plate, and 100 µL of microbial suspensions of S. mutans (Streptococcus mutans) and S. sobrinus (Streptococcus sobrinus) were inoculated then incubated at 37℃ for 24 hours. The bacterial attachment was tested by FACS (fluorescence-activated cell sorting) analysis after staining with fluorescent probe. RESULTS PtN were successfully loaded and uniformly immobilized into PMMA denture acrylic with a proper thermal stability and similar surface morphology as compared to control. PtNC expressed significant bacterial anti-adherent effect rather than bactericidal effect above 50 mg/L PtN loaded when compared to pristine PMMA (P=.01) with no or extremely small amounts of Pt ion eluted. CONCLUSION This is the first report on the synthesis and its antibacterial activity of Pt-PMMA nanocomposite. PMMA denture acrylic loading PtN could be a possible intrinsic antimicrobial denture material with proper mechanical characteristics, meeting those specified for denture bases. For clinical application, future studies including biocompatibility, color stability and warranting the long-term effect were still required. PMID:25006385

  1. The bond strength of elastomer tray adhesives to thermoplastic and acrylic resin tray materials.

    PubMed

    Hogans, W R; Agar, J R

    1992-04-01

    This study evaluated the bond strength of selected impression materials (Permlastic, Express, and Hydrosil) to a thermoplastic custom tray material as a function of drying time of the adhesive after application to a tray material. In addition, bond strengths of a polysulfide impression material to an acrylic resin tray material and to a thermoplastic tray material made directly against wax were evaluated. Bond strengths were obtained directly from values of applied load at failure and important conclusions were drawn. PMID:1507140

  2. Inhibition of the polymerization of methyl methacrylate and methyl acrylate by mixtures of chloranil with phenothiazine

    SciTech Connect

    Ivanov, A.A; Lysenko, G.M.; Zholina, I.N.

    1985-09-01

    This paper investigates the kinetic peculiarities of inhibited polymerization of methyl methacrylate and methyl acrylate in the presence of mixtures of chloranil with phenothiazine. It is shown that depending on the structure of the monomer and the concentrations of the electron donor and electron acceptor, the radicals of propagation may form complexes with chloranil or with phenothiazine at the first step of the inhibition reaction or may interact with the complex (phenothiazine to chloranil).

  3. Transdermal Nitroglycerin Delivery Using Acrylic Matrices: Design, Formulation, and In Vitro Characterization

    PubMed Central

    Ramazani Saadat Abadi, Ahmad

    2014-01-01

    Nitroglycerin (TNG) transdermal drug delivery systems (TDDSs) with different acrylic pressure-sensitive adhesives (PSAs) and chemical permeation enhancers (CPEs) were prepared. The effects of PSAs and CPEs types and concentrations on skin permeation and in vitro drug release from devices were evaluated using the dissolution method as well as the modified-jacketed Franz diffusion cells fitted with excised rat abdominal skin. It was demonstrated that the permeation rate or steady state flux (Jss) of the drug through the excised rat skin was dependent on the viscosity and type of acrylic PSA as well as the type of CPE. Among different acrylic PSAs, Duro-Tak 2516 and Duro-Tak 2054 showed the highest and Duro-Tak 2051 showed the lowest Jss. Among the various CPEs, propylene glycol and cetyl alcohol showed the highest and the lowest enhancement of the skin permeation of TNG, respectively. The adhesion properties of devices such as 180° peel strength and probe tack values were obtained. It was shown that increasing the concentration of CPE led to reduction in the adhesion property of PSA. Moreover, after optimization of the formulation, it was found that the use of 10% PG as a CPE and 25% nitroglycerin loading in Duro-Tak 2054 is an effective monolithic DIAP for the development of a transdermal therapeutic system for nitroglycerin. PMID:24511396

  4. Effect of Antiadherents on the Physical and Drug Release Properties of Acrylic Polymeric Films.

    PubMed

    Ammar, Hussein O; Ghorab, Mamdouh M; Felton, Linda A; Gad, Shadeed; Fouly, Aya A

    2016-06-01

    Antiadherents are used to decrease tackiness of a polymer coating during both processing and subsequent storage. Despite being a common excipient in coating formulae, antiadherents may affect mechanical properties of the coating film as well as drug release from film-coated tablets, but how could addition of antiadherents affect these properties and to what extent and is there a relation between the physical characteristics of the tablet coat and the drug release mechanisms? The aim of this study was to evaluate physical characteristics of films containing different amounts of the antiadherents talc, glyceryl monostearate, and PlasACRYL(TM) T20. Eudragit RL30D and Eudragit RS30D as sustained release polymers and Eudragit FS30D as a delayed release material were used. Polymer films were characterized by tensile testing, differential scanning calorimetry (DSC), microscopic examination, and water content as calculated from loss on drying. The effect of antiadherents on in vitro drug release for the model acetylsalicylic acid tablets coated with Eudragit FS30D was also determined. Increasing talc concentration was found to decrease the ability of the polymer films to resist mechanical stress. In contrast, glyceryl monostearate (GMS) and PlasACRYL produced more elastic films. Talc at concentrations higher than 25% caused negative effects, which make 25% concentration recommended to be used with acrylic polymers. All antiadherents delayed the drug release at all coating levels; hence, different tailoring of drug release may be achieved by adjusting antiadherent concentration with coating level. PMID:26314244

  5. Transscleral fixation of closed loop haptic acrylic posterior chamber intraocular lens in aphakic nonvitrectomized eyes

    PubMed Central

    Agrawal, Siddharth; Singh, Vinita; Gupta, Sanjiv Kumar; Misra, Nibha; Srivastava, Rajat M

    2015-01-01

    Purpose: To evaluate the outcome of transscleral fixation of closed loop haptic acrylic posterior chamber intraocular lens (PCIOL) in aphakia in nonvitrectomized eyes. Materials and Methods: Patients with postcataract surgery aphakia, trauma with posterior capsule injury, subluxated crystalline lens, and per operative complications where sulcus implantation was not possible were included over a 1-year period. Scleral fixation of acrylic hydrophilic PCIOL was performed according to the described technique, and the patients were evaluated on the day 1, 3, 14, and at 3 and 12 months postoperatively for IOL centration, pseudophakodonesis, change in best-corrected visual acuity (BCVA), and any other complications. Results: Out of twenty-nine eyes of 24 patients, who completed the study, 25 (86.2%) eyes had improved, 2 (6.9%) eyes showed no change, and 2 (6.9%) eyes had worsening of BCVA. Three (10.3%) eyes developed postoperative complications. A significant improvement in mean BCVA (P < 0.0001) was observed after the procedure. Mean duration of follow-up was 26.2 months (range 22–35 months). Conclusion: The use of closed loop haptic acrylic IOL for scleral fixation appears to be safe and effective alternative to conventional scleral fixated polymethyl methacrylate intraocular lenses. PMID:26576522

  6. An Electrochemical DNA Microbiosensor Based on Succinimide-Modified Acrylic Microspheres

    PubMed Central

    Ulianas, Alizar; Heng, Lee Yook; Hanifah, Sharina Abu; Ling, Tan Ling

    2012-01-01

    An electrochemical microbiosensor for DNA has been fabricated based on new acrylic microspheres modified with reactive N-acryloxysuccinimide (NAS) functional groups. Hydrophobic poly(n-butylacrylate-N-acryloxysuccinimide) microspheres were synthesized in an emulsion form with a simple one-step photopolymerization technique. Aminated DNA probe was attached to the succinimde functional group of the acrylic microspheres via covalent bonding. The hybridization of the immobilized DNA probe with the complementary DNA was studied by differential pulse voltametry using anthraquninone-2-sulfonic acid monohydrate sodium salt (AQMS) as the electroactive hybridization label. The influences of many factors such as duration of DNA probe immobilization and hybridization, pH, type of ions, buffer concentrations, ionic strength, operational temperature and non-complementary DNA on the biosensor performance were evaluated. Under optimized conditions, the DNA microbiosensor demonstrated a linear response range to target DNA over a wide concentration range of 1.0 × 10−16 and 1.0 × 10−8 M with a lower limit of detection (LOD) of 9.46 × 10−17 M (R2 = 0.97). This DNA microbiosensor showed good reproducibility with 2.84% RSD (relative standard deviation) (n = 3). Application of the NAS-modified acrylic microspheres in the construction of DNA microbiosensor had improved the overall analytical performance of the resultant DNA microbiosensor when compared with other reported DNA biosensors using other nano-materials for membranes and microspheres as DNA immobilization matrices. PMID:22778594

  7. UV curable polyester polyol acrylate/bentonite nanocomposites: synthesis, characterization, and drug release.

    PubMed

    Thatiparti, Thimma Reddy; Tammishetti, Shekharam; Nivasu, Muram V

    2010-01-01

    Polyesterpolyolacrylate/bentonite nanocomposites, capable of in situ photo polymerization, were synthesized and characterized. The organically modified bentonite clay was prepared by an ion exchange process, in which sodium ions were replaced by alkyl ammonium ions. Organo modification of bentonite was confirmed from X-ray diffraction and fourier transform-infrared data. Microstructures were characterized by XRD data and transmission electron microscopy (TEM). Both XRD data and TEM images of polyester polyol acrylate/organo modified bentonite nanocomposites indicated that most of silicate layers were intercalated into the acrylate matrix. The resulting nanocomposites were characterized by gel content, water equilibrium swell, tensile strength, and in vitro degradation. The results showed that water equilibrium swell and in vitro degradation of these nanocomposites decreased with increase in the clay content. The tensile strength of these nanocomposites also increased with increase in the clay content. Release of two model drugs namely sulfamethoxazole and diclofenac sodium (DS) from these nanocomposites was studied in phosphate buffer saline pH = 7.4 at 37 degrees C. The drug release studies showed that sulfamethoxazole released slower than DS from polyester polyol acrylate nanocomposites. Therefore, these materials may be useful for mucoadhesive drug carriers and other biomedical applications. PMID:19904735

  8. A Potentiometric Formaldehyde Biosensor Based on Immobilization of Alcohol Oxidase on Acryloxysuccinimide-modified Acrylic Microspheres

    PubMed Central

    Ling, Yew Pei; Heng, Lee Yook

    2010-01-01

    A new alcohol oxidase (AOX) enzyme-based formaldehyde biosensor based on acrylic microspheres has been developed. Hydrophobic poly(n-butyl acrylate-N-acryloxy-succinimide) [poly(nBA-NAS)] microspheres, an enzyme immobilization matrix, was synthesized using photopolymerization in an emulsion form. AOX-poly(nBA-NAS) microspheres were deposited on a pH transducer made from a layer of photocured and self-plasticized polyacrylate membrane with an entrapped pH ionophore coated on a Ag/AgCl screen printed electrode (SPE). Oxidation of formaldehyde by the immobilized AOX resulted in the production of protons, which can be determined via the pH transducer. Effects of buffer concentrations, pH and different amount of immobilization matrix towards the biosensor’s analytical performance were investigated. The formaldehyde biosensor exhibited a dynamic linear response range to formaldehyde from 0.3–316.2 mM and a sensitivity of 59.41 ± 0.66 mV/decade (R2 = 0.9776, n = 3). The lower detection limit of the biosensor was 0.3 mM, while reproducibility and repeatability were 3.16% RSD (relative standard deviation) and 1.11% RSD, respectively (n = 3). The use of acrylic microspheres in the potentiometric formaldehyde biosensor improved the biosensor’s performance in terms of response time, linear response range and long term stability when compared with thick film immobilization methods. PMID:22163450

  9. Transdermal nitroglycerin delivery using acrylic matrices: design, formulation, and in vitro characterization.

    PubMed

    Savoji, Houman; Mehdizadeh, Amir; Ramazani Saadat Abadi, Ahmad

    2014-01-01

    Nitroglycerin (TNG) transdermal drug delivery systems (TDDSs) with different acrylic pressure-sensitive adhesives (PSAs) and chemical permeation enhancers (CPEs) were prepared. The effects of PSAs and CPEs types and concentrations on skin permeation and in vitro drug release from devices were evaluated using the dissolution method as well as the modified-jacketed Franz diffusion cells fitted with excised rat abdominal skin. It was demonstrated that the permeation rate or steady state flux (J ss) of the drug through the excised rat skin was dependent on the viscosity and type of acrylic PSA as well as the type of CPE. Among different acrylic PSAs, Duro-Tak 2516 and Duro-Tak 2054 showed the highest and Duro-Tak 2051 showed the lowest J ss. Among the various CPEs, propylene glycol and cetyl alcohol showed the highest and the lowest enhancement of the skin permeation of TNG, respectively. The adhesion properties of devices such as 180° peel strength and probe tack values were obtained. It was shown that increasing the concentration of CPE led to reduction in the adhesion property of PSA. Moreover, after optimization of the formulation, it was found that the use of 10% PG as a CPE and 25% nitroglycerin loading in Duro-Tak 2054 is an effective monolithic DIAP for the development of a transdermal therapeutic system for nitroglycerin. PMID:24511396

  10. Determination of acrylamide and acrylic acid by isocratic liquid chromatography with pulsed electrochemical detection.

    PubMed

    Casella, Innocenzo G; Pierri, Marianna; Contursi, Michela

    2006-02-24

    The electrochemical behaviour of the polycrystalline platinum electrode towards the oxidation/reduction of short-chain unsaturated aliphatic molecules such as acrylamide and acrylic acid was investigated in acidic solutions. Analytes were separated by reverse phase liquid chromatographic and quantified using a pulsed amperometric detection. A new two-step waveform, is introduced for detection of acrylamide and acrylic acid. Detection limits (LOD) of 20 nM (1. 4 microg/kg) and 45 nM (3.2 microg/kg) were determined in water solutions containing acrylamide and acrylic acid, respectively. Compared to the classical three-step waveform, the proposed two-step waveform shows favourable analytical performance in terms of LOD, linear range, precision and improved long-term reproducibility. The proposed analytical method combined with clean-up procedure accomplished by Carrez clearing reagent and subsequent extraction with a strong cation exchanger cartridges (SPE), was successfully used for the quantification of low concentrations of acrylamide in foodstuffs such as coffee and potato fries. PMID:16426623

  11. [Capability and microbial community analysis of a membrane bioreactor for acrylic fiber wastewater treatment].

    PubMed

    Wei, Jian; Song, Yong-Huil; Zhao, Le

    2014-12-01

    Sequencing batch membrane bioreactor (SBMBR) was used for the treatment of acrylic fiber polymerization wastewater and acrylonitrile wastewater. The operation efficiencies of SBMBR under different wastewater ratios and operation conditions were investigated, and the microbial community structure of the SBMBR system was analyzed by using PCR-DGGE technology. The results showed that SBMBR had a high removal efficiency on pollutants in acrylic fiber wastewater, and the lacking of carbon source and alkalinity were the main limiting factors for nitrogen removal. Under the designed operation conditions of 90 min anoxic/150 min aerobic cyclic operation and HRT of 24 h, the average COD, NH4(+) -N and TN removal efficiencies were 82.5%, 98.7% and 74.6%, respectively. The effluent of the SBMBR could steadily meet the Grade I standards of the Wastewater Comprehensive Discharge Standard of China (GB 8978-1996). The PCR-DGGE analyses showed that the microbial communities in SBMBR had a significant shift with the changes of influent characteristics and operation conditions. By cloning and sequencing analyses of selected dominant bacteria, 22 16S rDNA sequence were successfully identified from 9 sludge samples, from which 7 dominant functional microorganisms for the degradation of organic pollutants in acrylic fiber wastewater were screened out. PMID:25826932

  12. Transdermal thiol-acrylate polyethylene glycol hydrogel synthesis using near infrared light.

    PubMed

    Chung, Solchan; Lee, Hwangjae; Kim, Hyung-Seok; Kim, Min-Gon; Lee, Luke P; Lee, Jae Young

    2016-08-01

    Light-induced polymerization has been widely applied for hydrogel synthesis, which conventionally involves the use of ultraviolet or visible light to activate a photoinitiator for polymerization. However, with these light sources, transdermal gelation is not efficient and feasible due to their substantial interactions with biological systems, and thus a high power is required. In this study, we used biocompatible and tissue-penetrating near infrared (NIR) light to remotely trigger a thiol-acrylate reaction for efficient in vivo gelation with good controllability. Our gelation system includes gold nanorods as a photothermal agent, a thermal initiator, diacrylate polyethylene glycol (PEG), and thiolated PEG. Irradiation with a low-power NIR laser (0.3 W cm(-2)) could induce gelation via a mixed-mode reaction with a small increase in temperature (∼5 °C) under the optimized conditions. We also achieved successful transdermal gelation via the NIR-assisted photothermal thiol-acryl reactions. This new type of NIR-assisted thiol-acrylate polymerization provides new opportunities for in situ hydrogel formation for injectable hydrogels and delivery of drugs/cells for various biomedical applications. PMID:27389611

  13. Aluminum nanoparticle/acrylate copolymer nanocomposites for dielectric elastomers with high dielectric constants

    NASA Astrophysics Data System (ADS)

    Hu, Wei; Zhang, Suki N.; Niu, Xiaofan; Liu, Chao; Pei, Qibing

    2014-03-01

    Dielectric elastomers are useful for large-strain actuation and energy harvesting. Their application has been limited by their low dielectric constants and consequently high driving voltage. Various fillers with high dielectric constants have been incorporated into different elastomer systems to improve the actuation strain, force output and energy density of the compliant actuators and generators. However, agglomeration may happen in these nanocomposites, resulting in a decrease of dielectric strength, an increase of leakage current, and in many instances the degree of enhancement of the dielectric constant. In this work, we investigated aluminum nanoparticles as nanofillers for acrylate copolymers. This metallic nanoparticle was chosen because the availability of free electrons could potentially provide an infinite value of dielectric constant as opposed to dielectric materials including ferroelectric nanocrystals. Moreover, aluminum nanoparticles have a self-passivated oxide shell effectively preventing the formation of conductive path. The surfaces of the aluminum nanoparticles were functionalized with methacrylate groups to assist the uniform dispersion in organic solutions and additionally enable copolymerization with acrylate copolymer matrix during bulk polymerization, and thus to suppress large range drifting of the nanoparticles. The resulting Al nanoparticle-acrylate copolymer nanocomposites were found to exhibit higher dielectric constant and increased stiffness. The leakage current under high electric fields were significantly lower than nanocomposites synthesized without proper nanoparticle surface modification. The dielectric strengths of the composites were comparable with the pristine polymers. In dielectric actuation evaluation, the actuation force output and energy specific work density were enhanced in the nanocomposites compared to the pristine copolymer.

  14. Impact and Flexural Strength, and Fracture Morphology of Acrylic Resins With Impact Modifiers

    PubMed Central

    Faot, Fernanda; Panza, Leonardo H V; Garcia, Renata C M Rodrigues; Cury, Altair Antoninha Del Bel

    2009-01-01

    Objectives: This study evaluated the impact and flexural strength and analyzed the fracture behavior of acrylic resins. Methods: Eighteen rectangular specimens were fabricated of Lucitone 550, QC 20 (both unreinforced acrylic resins), Impact 1500 (extra strength impact), Impact 2000 (high impact) according to the manufacturers’ instructions. The impact strength was evaluated in notched specimens (50x6x4mm) and flexural strength in unotched (64x10x3.3mm), using three-point bending test, as well as, stress at yield, Young modulus and displacement at yield. Fragments from mechanical tests were observed by SEM. Data from impact strength, stress at yield and displacement at yield were analyzed by 1-way ANOVA and Tukey test (α=0.05). Young modulus values were analyzed by One-way ANOVA and Dunnett T3 multiple comparisons test (α=0.05). Results: Mean values of impact strength and stress at yield values were higher (P<.005) for Impact 2000 while Young modulus was higher (P<.05) for Lucitone 550; Impact 1500 and Impact 2000 showed significant values (P<.05) in the displacement at yield. Impact fractures of the all acrylic resins were brittle. Bending fractures of Lucitone 550 and Impact 2000 were brittle, QC 20 fractures were ductile and Impact 1500 showed brittle (75%) and ductile (25%) fractures. Conclusion: Within the limitations of this study, the Impact 2000 showed improved mechanical properties with high capacity of stress absorption and energy dissipation before the fracture. PMID:19657461

  15. The impact of polymerization method on tensile bond strength between denture base and acrylic teeth.

    PubMed

    Hashem, Mohamed; Binmgren, Mohammed A; Alsaleem, Samah O; Vellappally, Sajith; Assery, Mansour K; Sukumaran, Anil

    2014-01-01

    Failure of the bond between acrylic teeth and the denture base resin interface is one of the major concern in prosthodontics. The new generation of denture bases that utilize alternate polymerization methods are being introduced in the market. The aim of the study is to evaluate the influence of polymerization methods on bonding quality between the denture base and artificial teeth. Sixty test specimens were prepared (20 in each group) and were polymerized using heat, microwave and visible light curing. The tensile strength was recorded for each of the samples, and the results were analyzed statistically. The light-activated Eclipse™ System showed the highest tensile strength, followed by heat curing. The microwave-cured samples exhibited the least bonding to the acrylic teeth. Within the limitations of this study, it can be concluded that the new generation of light-cured denture bases showed significantly better bonding to acrylic teeth and can be used as an alternative to the conventional heat-polymerized denture base. PMID:25307813

  16. Effect of Nanosilver on Thermal and Mechanical Properties of Acrylic Base Complete Dentures

    PubMed Central

    Hamedi-Rad, Fahimeh; Ghaffari, Tahereh; Rezaii, Farzad; Ramazani, Ali

    2014-01-01

    Objective: Polymethyl methacrylate (PMMA), widely used as a prosthodontic base, has many disadvantages, including a high thermal expansion coefficient and low thermal conductivity, a low elasticity coefficient, low impact strength and low resistance to fatigue. This study aimed to make an in vitro comparison of the thermal conductivity, compressive strength, and tensile strength of the acrylic base of complete dentures with those of acrylic reinforced with nanosilver. Materials and Methods: For this study, 36 specimens were prepared. The specimens were divided into three groups of 12; which were further divided into two subgroups of control (unmodified PMMA) and test (PMMA mixed with 5 weight% nanosilver).The results were analysed by Independent t-test. Results: This study showed that the mean thermal conductivity and compressive strength of PMMA reinforced with nanosilver were significantly higher than the unmodified PMMA (P<0.05), while the tensile strength decreased significantly after the incorporation of nanosilver (P<0.05). Conclusion: Considering our results suggesting the favorable effect of silver nanoparticles on improving the thermal conductivity and compressive strength of PMMA, use of this material in the palatal area of maxillary acrylic resin dentures is recommended. PMID:25628675

  17. New polymer for 157-nm single-layer resist based on fluorine-containing acryl copolymer

    NASA Astrophysics Data System (ADS)

    Ogata, Toshiyuki; Endo, Koutaro; Komano, Hiroshi; Nakayama, Toshimasa

    2001-08-01

    We are reporting on the development of acryl polymer based on novel methacrylate and acrylate monomers with various trifluoromethyl groups for the application to 157nm chemically amplified positive-tone resists. The (alpha) - trifluoromethylation of the alkyl ester in methacrylate or acrylate could employ the reduction of acrylpolymer absorbance at 157nm by spectra analysis with the VUV-200 spectrophotometer by JASCO. Although the trifluoromethyl groups could employ the reduction of base polymer absorbance at 157nm, the homopolymers have issued weak etch resistance as a photoresist base polymer. To take account of this issue, we have developed a novel monomer, trifluoromethyl- iso-adamantylmethacrylate (TFIAdMA) and a new co-polymer system with the combination of fluorinated methacrylate derivatives and substituted p-hydroxystyrene. The absorption coefficient of poly(p-tert-butoxystyren-co- hexafluoro-tert-butyl methacrylate-co-methacrylic acid) incicated to be less than 3 micrometers -1 at 157nm. Patterning results were obtained with a 157nm contact exposure system of VUVES-4500 by LTJ. One of the experimental resists, based on a particular polymer ratio and photo acid generator, has clearly achieved 180nm line and space pattern resolution. At 140nm resist film thickness, the sensitivity was 31 mJ/cm2 when using 0,26N tetrametylammonium hydroxide surfactant type developer.

  18. Dimensional Changes of Acrylic Resin Denture Bases: Conventional Versus Injection-Molding Technique

    PubMed Central

    Gharechahi, Jafar; Asadzadeh, Nafiseh; Shahabian, Foad; Gharechahi, Maryam

    2014-01-01

    Objective: Acrylic resin denture bases undergo dimensional changes during polymerization. Injection molding techniques are reported to reduce these changes and thereby improve physical properties of denture bases. The aim of this study was to compare dimensional changes of specimens processed by conventional and injection-molding techniques. Materials and Methods: SR-Ivocap Triplex Hot resin was used for conventional pressure-packed and SR-Ivocap High Impact was used for injection-molding techniques. After processing, all the specimens were stored in distilled water at room temperature until measured. For dimensional accuracy evaluation, measurements were recorded at 24-hour, 48-hour and 12-day intervals using a digital caliper with an accuracy of 0.01 mm. Statistical analysis was carried out by SPSS (SPSS Inc., Chicago, IL, USA) using t-test and repeated-measures ANOVA. Statistical significance was defined at P<0.05. Results: After each water storage period, the acrylic specimens produced by injection exhibited less dimensional changes compared to those produced by the conventional technique. Curing shrinkage was compensated by water sorption with an increase in water storage time decreasing dimensional changes. Conclusion: Within the limitations of this study, dimensional changes of acrylic resin specimens were influenced by the molding technique used and SR-Ivocap injection procedure exhibited higher dimensional accuracy compared to conventional molding. PMID:25584050

  19. Poly(ε-caprolactone)-based copolymers bearing pendant cyclic ketals and reactive acrylates for the fabrication of photocrosslinked elastomers.

    PubMed

    Yang, Xiaowei; Cui, Chengzhong; Tong, Zhixiang; Sabanayagam, Chandran R; Jia, Xinqiao

    2013-09-01

    Block copolymers of poly(ethylene glycol) and poly(ε-caprolactone) (PCL) with chemically addressable functional groups were synthesized and characterized. Ring-opening polymerization of ε-caprolactone (CL) and 1,4,8-trioxaspiro-[4,6]-9-undecanone (TSU) using α-methoxy, ω-hydroxyl poly(ethylene glycol) as the initiator afforded a copolymer with cyclic ketals being randomly distributed in the hydrophobic PCL block. At an initiator/catalyst molar ratio of 10/1 and a TSU/CL weight ratio of 1/4, a ketal-carrying copolymer (ECT2-CK) with Mn of 52 kDa and a ketal content of 15 mol.% was obtained. Quantitative side-chain deacetalization revealed the reactive ketones without noticeable polymer degradation. In our study, 10 mol.% of cyclic ketals were deprotected and the ketone-containing copolymer was designated as ECT2-CO. Reaction of ECT2-CO with 2-(2-(aminooxy)acetoxy)-ethyl acrylate gave rise to an acrylated product (ECT2-AC) containing an estimated 3-5 acrylate groups per chain. UV-initiated radical polymerization of ECT2-AC in dichloromethane resulted in a crosslinked network (xECT2-AC). Thermal and morphological analyses employing differential scanning calorimetry and atomic force microscopy operated in PeakForce Tapping mode revealed the semicrystalline nature of the network, which contained stiff crystalline lamellae dispersed in a softer amorphous interstitial. Macroscopic and nanoscale mechanical characterizations showed that ECT2-CK exhibited a significantly lower modulus than PCL of a similar molecular weight. Whereas ECT2-CK undergoes a plastic deformation with a distinct yield point and a cold-drawing region, xECT2-AC exhibits a compliant, elastomeric deformation with a Young's modulus of 0.5±0.1 MPa at 37°C. When properly processed, the crosslinked network exhibited shape-memory behaviors, with shape fixity and shape recovery values close to 1 and a shape recovery time of less than 4s at 37°C. In vitro studies showed that xECT2-AC films did not induce

  20. FTIR gas-phase kinetic study on the reactions of some acrylate esters with OH radicals and Cl atoms.

    PubMed

    Moreno, A; Gallego-Iniesta, M P; Taccone, R; Martín, M P; Cabañas, B; Salgado, M S

    2014-10-01

    Acrylate esters are α,β-unsaturated esters that contain vinyl groups directly attached to the carbonyl carbon. These compounds are widely used in the production of plastics and resins. Atmospheric degradation processes of these compounds are currently not well understood. The kinetics of the gas phase reactions of OH radicals with methyl 3-methylacrylate and methyl 3,3-dimethylacrylate were determined using the relative rate technique in a 50 L Pyrex photoreactor using in situ FTIR spectroscopy at room temperature (298 ± 2 K) and atmospheric pressure (708 ± 8 Torr) with air as the bath gas. Rate coefficients obtained were (in units cm(3) molecule(-1) s(-1)): (3.27 ± 0.33) × 10(-11) and (4.43 ± 0.42) × 10(-11), for CH3CH═CHC(O)OCH3 and (CH3)2CH═CHC(O)OCH3, respectively. The same technique was used to study the gas phase reactions of hexyl acrylate and ethyl hexyl acrylate with OH radicals and Cl atoms. In the experiments with Cl, N2 and air were used as the bath gases. The following rate coefficients were obtained (in cm(3) molecule(-1) s(-1)): k3 (CH2═CHC(O)O(CH2)5CH3 + Cl) = (3.31 ± 0.31) × 10(-10), k4(CH2═CHC(O)OCH2CH(CH2CH3)(CH2)3CH3 + Cl) = (3.46 ± 0.31) × 10(-10), k5(CH2═CHC(O)O(CH2)5CH3 + OH) = (2.28 ± 0.23) × 10(-11), and k6(CH2═CHC(O)OCH2CH(CH2CH3)(CH2)3CH3 + OH) = (2.74 ± 0.26) × 10(-11). The reactivity increased with the number of methyl substituents on the double bond and with the chain length of the alkyl group in -C(O)OR. Estimations of the atmospheric lifetimes clearly indicate that the dominant atmospheric loss process for these compounds is their daytime reaction with the hydroxyl radical. In coastal areas and in some polluted environments, Cl atom-initiated degradation of these compounds can be significant, if not dominant. Maximum Incremental Reactivity (MIR) index and global warming potential (GWP) were also calculated, and it was concluded that these compounds have significant MIR values, but they do

  1. Poly(ε-Caprolactone)-Based Copolymers Bearing Pendant Cyclic Ketals and Reactive Acrylates for the Fabrication of Photocrosslinked Elastomers

    PubMed Central

    Yang, Xiaowei; Cui, Chengzhong; Tong, Zhixiang; Sabanayagam, Chandran R.; Jia, Xinqiao

    2013-01-01

    Block copolymers of poly(ethylene glycol) (PEG) and poly(ε-caprolactone) (PCL) with chemically addressable functional groups were synthesized and characterized. Ring opening polymerization of ε-caprolactone (CL) and 1,4,8-trioxaspiro-[4,6]-9-undecanone (TSU) using α-methoxy, ω-hydroxyl poly(ethylene glycol) (mPEG) as the initiator afforded a copolymer with cyclic ketals being randomly distributed in the hydrophobic PCL block. At an initiator/catalyst molar ratio of 10/1 and a TSU/CL weight ratio of 1/4, a ketal-carrying copolymer (ECT2-CK) with Mn of 52 kDa and a ketal content of 15 mol% was obtained. Quantitative side chain deacetalization revealed the reactive ketones without noticeable polymer degradation. In our study, 10 mol% of cyclic ketals were deprotected and the ketone-containing copolymer was designated as ECT2-CO. Reaction of ECT2-CO with 2-(2-(aminooxy)acetoxy)-ethyl acrylate gave rise to an acrylated product (ECT2-AC) containing an estimated 3–5 acrylate groups per chain. UV-initiated radical polymerization of ECT2-AC in dichloromethane resulted in a crosslinked network (xECT2-AC). Thermal and morphological analyses employing Differential Scanning Calorimetry (DSC) and Atomic Force Microscopy (AFM) operated in PeakForce Tapping mode revealed the semicrystalline nature of the network, containing stiff crystalline lamellae dispersed in a softer amorphous interstitial. Macroscopic and nanoscale mechanical characterizations showed that ECT2-CK exhibited a significantly lower modulus than PCL of a similar molecular weight. While ECT2-CK undergoes a plastic deformation with a distinct yield point and a cold drawing region, xECT2-AC exhibited a compliant, elastomeric deformation with a Young’s modulus of 0.5 ± 0.1 MPa at 37 °C. When properly processed, the crosslinked network exhibited shape memory behaviors, with shape fixity and shape recovery values close to 1 and a shape recovery time of less than 4 s at 37 °C. In vitro studies showed that x

  2. Calcium Phosphate Mineralization in Cellulose Derivative/Poly(acrylic acid) Composites Having a Chiral Nematic Mesomorphic Structure.

    PubMed

    Ogiwara, Takuya; Katsumura, Ayaka; Sugimura, Kazuki; Teramoto, Yoshikuni; Nishio, Yoshiyuki

    2015-12-14

    Calcium phosphate mineralization was conducted by using polymer composites of liquid-crystalline (ethyl)cellulose (EC) or (hydroxypropyl)cellulose (HPC) with poly(acrylic acid) (PAA) as a scaffolding medium for the inorganic deposition. The EC/PAA and HPC/PAA samples were prepared in colored film form from EC and HPC lyotropic liquid crystals of left-handed and right-handed chiral nematics, respectively, by polymerization and cross-linking of acrylic acid as the main solvent component. The mineralization was allowed to proceed in a batchwise operation by soaking the liquid-crystalline films in an aqueous salt solution containing the relevant ions, Ca(2+) and HPO4(2-). The calcium phosphate-deposited EC/PAA and HPC/PAA composites (weight gain, typically 15-25% and 6-11%, respectively) retained the chiral nematic organization of the respective original handedness but exhibited selective light-reflection of longer wavelengths relative to that of the corresponding nonmineralized samples. From X-ray diffraction and energy-dispersive X-ray spectroscopy measurements, it was deduced that the calcium and phosphorus were incorporated inside the polymer matrices in three forms: amorphous calcium phosphate, hydroxyapatite, and a certain complex of PAA-Ca(2+). Dynamic mechanical analysis and thermogravimetry revealed that the inorganic hybridization remarkably enhanced the thermal and mechanical performance of the optically functionalized cellulosic/synthetic polymer composites; however, the effect was more drastic in the EC/PAA series rather than the HPC/PAA series, reflecting the difference in the deposited mineral amount between the two. PMID:26536381

  3. Thermodynamic Interactions between Polystyrene and Long-Chain Poly(n-Alkyl Acrylates) Derived from Plant Oils.

    PubMed

    Wang, Shu; Robertson, Megan L

    2015-06-10

    Vegetable oils and their fatty acids are promising sources for the derivation of polymers. Long-chain poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) are readily derived from fatty acids through conversion of the carboxylic acid end-group to an acrylate or methacrylate group. The resulting polymers contain long alkyl side-chains with around 10-22 carbon atoms. Regardless of the monomer source, the presence of alkyl side-chains in poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) provides a convenient mechanism for tuning their physical properties. The development of structured multicomponent materials, including block copolymers and blends, containing poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) requires knowledge of the thermodynamic interactions governing their self-assembly, typically described by the Flory-Huggins interaction parameter χ. We have investigated the χ parameter between polystyrene and long-chain poly(n-alkyl acrylate) homopolymers and copolymers: specifically we have included poly(stearyl acrylate), poly(lauryl acrylate), and their random copolymers. Lauryl and stearyl acrylate were chosen as model alkyl acrylates derived from vegetable oils and have alkyl side-chain lengths of 12 and 18 carbon atoms, respectively. Polystyrene is included in this study as a model petroleum-sourced polymer, which has wide applicability in commercially relevant multicomponent polymeric materials. Two independent methods were employed to measure the χ parameter: cloud point measurements on binary blends and characterization of the order-disorder transition of triblock copolymers, which were in relatively good agreement with one another. The χ parameter was found to be independent of the alkyl side-chain length (n) for large values of n (i.e., n > 10). This behavior is in stark contrast to the n-dependence of the χ parameter predicted from solubility parameter theory. Our study complements prior work investigating the interactions between

  4. A density functional study on dielectric properties of acrylic acid grafted polypropylene

    NASA Astrophysics Data System (ADS)

    Ruuska, Henna; Arola, Eero; Kortelainen, Tommi; Rantala, Tapio T.; Kannus, Kari; Valkealahti, Seppo

    2011-04-01

    Influence of acrylic acid grafting of isotactic polypropylene on the dielectric properties of the polymer is investigated using density functional theory (DFT) calculations, both in the molecular modeling and three-dimensional (3D) bulk periodic system frameworks. In our molecular modeling calculations, polarizability volume, and polarizability volume per mass which reflects the permittivity of the polymer, as well as the HOMO-LUMO gap, one of the important measures indicating the electrical breakdown voltage strength, were examined for oligomers with various chain lengths and carboxyl mixture ratios. When a polypropylene oligomer is grafted with carboxyl groups (cf. acrylic acid), our calculations show that the increase of the polarizability volume α' of the oligomer is proportional to the increase of its mass m, while the ratio {{α^ ' } { α^ ' } m} decreases from the value of a pure polymer when increasing the mixture ratio. The decreasing ratio of {{α^ ' } {α^ ' } m} under carboxyl grafting indicates that the material permittivity might also decrease if the mass density of the material remains constant. Furthermore, our calculations show that the HOMO-LUMO gap energy decreases by only about 15% in grafting, but this decrease seems to be independent on the mixture ratio of carboxyl. This indicates that by doping polymers with additives better dielectric properties can be tailored. Finally, using the first-principles molecular DFT results for polarizability volume per mass in connection with the classical Clausius-Mossotti relation, we have estimated static permittivity for acrylic acid grafted polypropylene, assuming the structural density keeping constant under grafting. The computed permittivity values are in a qualitative agreement with the recent experiments, showing increasing tendency of the permittivity as a function of the grafting composition. In order to validate our molecular DFT based approach, we have also carried out extensive three

  5. A density functional study on dielectric properties of acrylic acid grafted polypropylene.

    PubMed

    Ruuska, Henna; Arola, Eero; Kortelainen, Tommi; Rantala, Tapio T; Kannus, Kari; Valkealahti, Seppo

    2011-04-01

    Influence of acrylic acid grafting of isotactic polypropylene on the dielectric properties of the polymer is investigated using density functional theory (DFT) calculations, both in the molecular modeling and three-dimensional (3D) bulk periodic system frameworks. In our molecular modeling calculations, polarizability volume, and polarizability volume per mass which reflects the permittivity of the polymer, as well as the HOMO-LUMO gap, one of the important measures indicating the electrical breakdown voltage strength, were examined for oligomers with various chain lengths and carboxyl mixture ratios. When a polypropylene oligomer is grafted with carboxyl groups (cf. acrylic acid), our calculations show that the increase of the polarizability volume α' of the oligomer is proportional to the increase of its mass m, while the ratio α'/m decreases from the value of a pure polymer when increasing the mixture ratio. The decreasing ratio of α'/m under carboxyl grafting indicates that the material permittivity might also decrease if the mass density of the material remains constant. Furthermore, our calculations show that the HOMO-LUMO gap energy decreases by only about 15% in grafting, but this decrease seems to be independent on the mixture ratio of carboxyl. This indicates that by doping polymers with additives better dielectric properties can be tailored. Finally, using the first-principles molecular DFT results for polarizability volume per mass in connection with the classical Clausius-Mossotti relation, we have estimated static permittivity for acrylic acid grafted polypropylene, assuming the structural density keeping constant under grafting. The computed permittivity values are in a qualitative agreement with the recent experiments, showing increasing tendency of the permittivity as a function of the grafting composition. In order to validate our molecular DFT based approach, we have also carried out extensive three-dimensional bulk periodic first

  6. Development and characterization of amorphous acrylate networks for use as switchable adhesives inspired from shapememory behavior

    NASA Astrophysics Data System (ADS)

    Lakhera, Nishant

    Several types of insects and animals such as spiders and geckos are inherently able to climb along vertical walls and ceilings. This remarkable switchable adhesive behavior has been attributed to the fibrillar structures on their feet, with size ranging from few nanometers to a few micrometers depending on the species. Several studies have attempted to create synthetic micro-patterned surfaces trying to imitate this adhesive behavior seen in nature. The experimental procedures are scattered, with sole purpose of trying to increase adhesion, thereby making direct comparison between studies very difficult. There is a lack of fundamental understanding on adhesion of patterned surfaces. The influence of critical parameters like material modulus, glass transition temperature, viscoelastic effects, temperature and water absorption on adhesion is not fully explored and characterized. These parameters are expected to have a decisive influence on adhesion behavior of the polymer. Previous studies have utilized conventional "off-the-shelf" materials like epoxy, polyurethanes etc. It is however, impossible to change the material modulus, glass transition temperature etc. of these polymer systems without changing the base constituents itself, thereby explaining the gaps in the current research landscape. The purpose of this study was to use acrylate shape-memory polymers (SMPs) for their ability to be tailored to specific mechanical properties by control of polymer chemistry, without changing the base constituents. Polymer networks with tailorable glass transition, material modulus, water absorption etc. were developed and adhesion studies were performed to investigate the influence of temperature, viscoelastic effects, material modulus on the adhesion behavior of flat acrylate polymer surfaces. The knowledge base gained from these studies was utilized to better understand the fundamental mechanisms associated with adhesion behavior of patterned acrylate surfaces. Thermally

  7. Metabolism of acrylate to {beta}-hydroxypropionate and its role in dimethylsulfoniopropionate lyase induction by a salt marsh sediment bacterium, Alcaligenes faecalis M3A

    SciTech Connect

    Ansede, J.H.; Pellechia, P.J.; Yoch, D.C.

    1999-11-01

    Dimethylsulfoniopropionate (DMSP) is degraded to dimethylsulfide (DMS) and acrylate by the enzyme DMSP lyase. DMS or acrylate can serve as a carbon source for both free-living and endophytic bacteria in the marine environment. In this study, the authors report on the mechanism of DMSP-acrylate metabolism by Alcaligenes faecalis M3A. Suspensions of citrate-grown cells expressed a low level of DMSP lyase activity that could be induced to much higher levels in the presence of DMSP, acrylate, and its metabolic product, {beta}-hydroxypropionate. DMSP was degraded outside the cell, resulting in an extracellular accumulation of acrylate, which in suspensions of citrate-grown cells was then metabolized at a low endogenous rate. The inducible nature of acrylate metabolism was evidenced by both an increase in the rate of its degradation over time and the ability of acrylate-grown cells to metabolize this molecule at about an eight times higher rate than citrate-grown cells. Therefore, acrylate induces both its production (from DMSP) and its degradation by an acrylase enzyme. {sup 1}H and {sup 13}C nuclear magnetic resonance analyses were used to identify the products resulting from [1-{sup 13}C]acrylate metabolism. The results indicated that A.faecalis first metabolized acrylate to {beta}-hydroxypropionate outside the cell, which was followed by its intracellular accumulation and subsequent induction of DMSP lyase activity. In summary, the mechanism of DMSP degradation to acrylate and the subsequent degradation of acrylate to {beta}-hydroxypropionate in the aerobic {beta}-Proteobacterium A.faecalis has been described.

  8. Designing Visible Light-Cured Thiol-Acrylate Hydrogels for Studying the HIPPO Pathway Activation in Hepatocellular Carcinoma Cells.

    PubMed

    Lin, Tsai-Yu; Bragg, John C; Lin, Chien-Chi

    2016-04-01

    Various polymerization mechanisms have been developed to prepare peptide-immobilized poly(ethylene glycol) (PEG) hydrogels, a class of biomaterials suitable for studying cell biology in vitro. Here, a visible light mediated thiol-acrylate photopolymerization scheme is reported to synthesize dually degradable PEG-peptide hydrogels with controllable crosslinking and degradability. The influence of immobilized monothiol pendant peptide is systematically evaluated on the crosslinking of these hydrogels. Further, methods are proposed to modulate hydrogel crosslinking, including adjusting concentration of comonomer or altering the design of multifunctional peptide crosslinker. Due to the formation of thioether ester bonds, these hydrogels are hydrolytically degradable. If the dithiol peptide linkers used are susceptible to protease cleavage, these thiol-acrylate hydrogels can be designed to undergo partial proteolysis. The differences between linear and multiarm PEG-acrylate (i.e., PEGDA vs PEG4A) are also evaluated. Finally, the use of the mixed-mode thiol-acrylate PEG4A-peptide hydrogels is explored for in situ encapsulation of hepatocellular carcinoma cells (Huh7). The effects of matrix stiffness and integrin binding motif (e.g., RGDS) on Huh7 cell growth and HIPPO pathway activation are studied using PEG4A-peptide hydrogels. This visible light poly-merized thiol-acrylate hydrogel system represents an alternative to existing light-cured hydrogel platforms and shall be useful in many biomedical applications. PMID:26709469

  9. Radiation synthesis of eco-friendly water reducing sulfonated starch/acrylic acid hydrogel designed for cement industry

    NASA Astrophysics Data System (ADS)

    Abd El-Rehim, H. A.; Hegazy, El-Sayed A.; Diaa, D. A.

    2013-04-01

    Starch was treated with chlorosulfonic acid to obtain sulfonated starch. Acrylic acid/sulfonated starch semi-interpenetrated network IPN of different compositions was prepared using ionizing radiation. Swelling of prepared IPNs at different environmental conditions was studied. The possible use of sulfonated starch/acrylic acid IPN as a water-retarding agent in the cement industry was investigated. ζ-potential measurements were used to determine the stability of the colloidal cement—SS/AA and cement -poly-naphthalene sulfonic acid (SNF) water retarding mixtures. Sulfonated starch/acrylic acid water-retarding property was influenced by hydrogel concentration and composition. Sulfonated starch/acrylic acid IPN admixture has a great effect on the cement initial setting time. Using 2% of SS/AA or SNF resulted in an increase in initial setting time by 2 and 1 h respectively, if compared with native cement initial setting time. The results showed that the synthetic commercial super-plasticizers could be replaced by an eco-friendly water-retarding sulfonated starch/acrylic acid IPN in the cement industry.

  10. The Effect of Al2O3 Addition on the Thermal Diffusivity of Heat Activated Acrylic Resin

    PubMed Central

    Atla, Jyothi; Manne, Prakash; Gopinadh, A.; Sampath, Anche; Muvva, Suresh Babu; Kishore, Krishna; Sandeep, Chiramana; Chittamsetty, Harika

    2013-01-01

    Aim: This study aimed at investigating the effect of adding 5% to 20% by weight aluminium oxide powder (Al2O3) on thermal diffusivity of heat–polymerized acrylic resin. Material and Methods: Twenty five cylindrical test specimens with an embedded thermocouple were used to determine thermal diffusivity over a physiologic temperature range (0 to 70°C). The specimens were divided into five groups (5 specimens/group) which were coded A to E. Group A was the control group (unmodified acrylic resin specimens). The specimens of the remaining four groups were reinforced with 5%, 10%, 15%, and 20% Al2O3 by weight. Results were analysed by using one–way analysis of variance (ANOVA). Results: Test specimens which belonged to Group E showed the highest mean thermal diffusivity value of 10.7mm2/sec, followed by D (9.09mm2/sec), C (8.49mm2/sec), B(8.28mm2/sec) and A(6.48mm2/sec) groups respectively. Thermal diffusivities of the reinforced acrylic resins were found to be significantly higher than that of the unmodified acrylic resin. Thermal diffusivity was found to increase in proportion to the weight percentage of alumina filler. Conclusion: Al2O3 fillers have potential to provide increased thermal diffusivity. Increasing the heat transfer characteristics of the acrylic resin base material could lead to more patient satisfaction. PMID:24086917

  11. Minocycline-loaded cellulose nano whiskers/poly(sodium acrylate) composite hydrogel films as wound dressing.

    PubMed

    Bajpai, S K; Pathak, V; Soni, Bhawna

    2015-08-01

    In this work, antibiotic drug Minocycline (Mic) loaded cellulose nano-whiskers (CNWs)/poly(sodium acrylate) hydrogel films were prepared and investigated for their drug releasing capacity in physiological buffer solution (PBS) at 37 °C. The (CNWs)/poly(sodium acrylate) film, containing 9.7% (w/w) of CNWs, demonstrated Mic release of 2500 μg/g while the plain poly(acrylate) film showed 3100 μg/g of drug release. In addition, with the increase in the concentration of cross-linker N,N'-methylene bisacrylamide (MB) from to, the drug release from the resulting films decreased from 507 to 191 μg/g. The release exponent 'n' for films with different compositions was found in the range of 0.45 to 0.89, thus indicating non-Fickian release mechanism. The Schott model was employed to interpret the kinetic drug release data successfully. The film samples poly(SA) and CNWs/poly(SA) (both not containing drug) showed thrombus formation of 0.010±0.001 g and 0.007±0.001 g, respectively, thus showing the non-thrombogenic behavior. In percent Hemolysis, both of the film samples of 1.136±0.012 and 0.5±0.020, respectively, thus indicating non-hemolytic behavior. In addition, both of the film samples demonstrated protein adsorption of 49.02±0.59μ g/μL and 51.20±0.51 μg/μL per cm(2), thus revealing a fair degree of protein adsorption. Finally, the Mic-loaded films showed fair anti-fungal and antibacterial properties. PMID:25940526

  12. Effect of TiO2 Nanoparticles on Tensile Strength of Dental Acrylic Resins.

    PubMed

    Shirkavand, Saeed; Moslehifard, Elnaz

    2014-01-01

    Background and aims. Adding further fillers to dental resins may enhance their physical characteristics. The aim of this study was to evaluate the tensile strength of heat-curing acrylic resin reinforced by TiO2nanoparticles added into the resin matrix. Materials and methods. Commercially available TiO2 nanoparticles were obtained and characterized using X-ray diffrac-tion (XRD) and scanning electron microscopy (SEM) to determine their crystalline structure, particle size and morphology. TiO2-acrylic resin nanocomposite was prepared by mixing 0.5, 1 and 2 (wt%) of surface modified TiO2 nanoparticles in an amalgamator providing three groups of samples. Before curing, the obtained paste was packed into steel molds. After cur-ing, the specimens were removed from the molds. The tensile strength test samples were prepared according to ISO 1567. Results. Two crystalline phases were found in TiO2 nanoparticles including: (i) anatase as the major one, and (ii) rutile. The average particle size calculated according to the Scherrer equation was 20.4 nm, showing a normal size distribution. According to SEM images, the nanocomposite with 1wt% TiO2 nanoparticles had a better distribution compared to other groups. In addition, the group by 1wt% TiO2 exhibited higher tensile strength with a significant difference compared to other groups. ANOVA showed significant differences between the contents of TiO2 particles in acrylic resin (F = 22.19; P < 0.001). Conclusion. A considerable increase in tensile strength was observed with titania NPs reinforcement agents in 1wt% by weight. Further increase of TiO2 nanoparticles decreased the tensile strength. PMID:25587380

  13. Reinforcement of acrylic denture base resin by incorporation of various fibers.

    PubMed

    Chen, S Y; Liang, W M; Yen, P S

    2001-01-01

    This study was designed to evaluate improvements in the mechanical properties of acrylic resin following reinforcement with three types of fiber. Polyester fiber (PE), Kevlar fiber (KF), and glass fiber (GF) were cut into 2, 4, and 6 mm lengths and incorporated at concentrations of 1, 2, and 3% (w/w). The mixtures of resin and fiber were cured at 70 degrees C in a water bath for 13 h, then at 90 degrees C for 1 h, in 70 x 25 x 15 mm stone molds, which were enclosed by dental flasks. The cured resin blocks were cut to an appropriate size and tested for impact strength and bending strength following the methods of ASTM Specification No. 256 and ISO Specification No. 1567, respectively. Specimens used in the impact strength test were reused for the Knoop hardness test. The results showed that the impact strength tended to be enhanced with fiber length and concentration, particularly PE at 3% and 6 mm length, which was significantly stronger than other formulations. Bending strength did not change significantly with the various formulations when compared to a control without fiber. The assessment of Knoop hardness revealed a complex pattern for the various formulations. The Knoop hardness of 3%, 6 mm PE-reinforced resin was comparable to that of the other formulations except for the control without fiber, but for clinical usage this did not adversely affect the merit of acrylic denture base resin. It is concluded that, for improved strength the optimum formulation to reinforce acrylic resin is by incorporation of 3%, 6 mm length PE fibers. PMID:11241340

  14. Water Sorption and Flexural Strength of Thermoplastic and Conventional Heat-Polymerized Acrylic Resins

    PubMed Central

    Hemmati, Mohammad Ali; Vafaee, Fariborz

    2015-01-01

    Objectives: The aim of this study was to assess and compare the water sorption and flexural strength of thermoplastic and conventional acrylic resins. Materials and Methods: Water sorption and flexural strength were compared between a thermoplastic modified polymethyl methacrylate (PMMA) denture base resin (group A) and a heat-polymerized PMMA acrylic resin (group B) as the control group (n=10). A three-point bending test was carried out for flexural strength testing. For water sorption test, 10 disc-shaped samples were prepared. After desiccating, the samples were weighed and immersed in distilled water for seven days. Then, they were weighed again, and desiccated for the second and third times. Differences between the mean values in the two groups were analyzed using Student’s t-test. Results: The mean value of water sorption was 14.74±1.36 μg/mm3 in group A, and 19.11±0.90 μg/mm3 in group B; this difference was statistically significant (P< 0.001). The mean value of flexural strength was 88.21±8.63 MPa in group A and 77.77±9.49 MPa in group B. A significant difference was observed between the two groups (P= 0.019). Conclusion: Flexural strength of group A was significantly higher than that of group B, and its water sorption was significantly lower. Thus, thermoplastic resins can be a suitable alternative to conventional PMMA acrylic resins as denture base materials. PMID:26877737

  15. Influence of strontia on various properties of surgical simplex P acrylic bone cement and experimental variants.

    PubMed

    Lewis, Gladius; Xu, Jie; Madigan, Seamus; Towler, Mark R

    2007-11-01

    The fact that the composition of acrylic bone cement, as used in cemented primary arthroplasties, is not optimal has been highlighted in the literature. For example: (i) deleterious effects of the radiopacifier (BaSO(4) or ZrO(2) particles in the powder) have been reported; (ii) there is an indication that pre-polymerized poly(methylmethacrylate) (PMMA) beads in the powder may be dispensed with; and (iii) there is a strong consensus that the accelerator commonly used, N,N-dimethyl-p-toluidine (DMPT), is toxic and has many other undesirable properties. At the same time, the effectiveness of drugs that contain a strontium compound in treating the effects of osteoporosis has been explained in terms of the role of strontium in bone formation and resorption. This indicates that strontium compounds may also have desirable effects on osseointegration of arthroplasties. The present study is a detailed evaluation of 24 acrylic bone cement formulations comprising different relative amounts of BaSO(4), strontia (as an alternative radiopacifier), pre-polymerized PMMA beads and DMPT. A large number of properties of the curing and cured cement were determined, including setting time, polymerization rate, fracture toughness and fatigue life. The focus was on the radiopacifier, with the finding being that many properties of formulations that contained strontia were about the same or better than those for cements that contained BaSO(4). Thus, further developmental work on strontia-containing acrylic bone cements is justified, with a view to making them candidates for use in cemented primary arthroplasties. PMID:17512808

  16. Effect of TiO2 Nanoparticles on Tensile Strength of Dental Acrylic Resins

    PubMed Central

    Shirkavand, Saeed; Moslehifard, Elnaz

    2014-01-01

    Background and aims. Adding further fillers to dental resins may enhance their physical characteristics. The aim of this study was to evaluate the tensile strength of heat-curing acrylic resin reinforced by TiO2nanoparticles added into the resin matrix. Materials and methods. Commercially available TiO2 nanoparticles were obtained and characterized using X-ray diffrac-tion (XRD) and scanning electron microscopy (SEM) to determine their crystalline structure, particle size and morphology. TiO2-acrylic resin nanocomposite was prepared by mixing 0.5, 1 and 2 (wt%) of surface modified TiO2 nanoparticles in an amalgamator providing three groups of samples. Before curing, the obtained paste was packed into steel molds. After cur-ing, the specimens were removed from the molds. The tensile strength test samples were prepared according to ISO 1567. Results. Two crystalline phases were found in TiO2 nanoparticles including: (i) anatase as the major one, and (ii) rutile. The average particle size calculated according to the Scherrer equation was 20.4 nm, showing a normal size distribution. According to SEM images, the nanocomposite with 1wt% TiO2 nanoparticles had a better distribution compared to other groups. In addition, the group by 1wt% TiO2 exhibited higher tensile strength with a significant difference compared to other groups. ANOVA showed significant differences between the contents of TiO2 particles in acrylic resin (F = 22.19; P < 0.001). Conclusion. A considerable increase in tensile strength was observed with titania NPs reinforcement agents in 1wt% by weight. Further increase of TiO2 nanoparticles decreased the tensile strength. PMID:25587380

  17. IN VITRO ANTIFUNGAL ACTION OF DIFFERENT SUBSTANCES OVER MICROWAVED-CURED ACRYLIC RESINS

    PubMed Central

    Montagner, Henrique; Montagner, Francisco; Braun, Katia Olmedo; Peres, Paulo Edelvar Correa; Gomes, Brenda Paula Figueiredo de Almeida

    2009-01-01

    Objective: The presence of Candida albicans on the surfaces of denture-base acrylic resins is strongly related to the development of oral stomatitis. This study evaluated the antifungal action of different agents over microwave-cured acrylic resin without polishing specimens previously contaminated with Candida albicans. Material and Methods: Sixty specimens were immersed in BHI broth previously inoculated with the yeast and stored for 3 h at 37°C. They were divided into 5 experimental groups (n=10): G1: 2% chlorhexidine solution (10 min); G2: 0.5% sodium hypochlorite (10 min); G3: modified sodium hypochlorite (10 min); G4: effervescent agent (5 min); G5: hydrogen peroxide 10v (30 min). The specimens of the control group 1 (C1) were not disinfected. Ten additional specimens of the control group 2 (C2) were not infected with the yeast, aiming to check the asepsis during the experiment. The disinfection agents were neutralized and the acrylic resin specimens were immersed in BHI Broth for 24 h. Culture media turbidity was evaluated spectrophotometrically according to the transmittance degree, i.e. the higher the transmittance the stronger the antimicrobial action. Statistical analysis was performed (Kruskal-Wallis Test, p<0.05). Results: The results, represented by the medians, were: G1 = 40; G2 = 100; G3 = 100; G4 = 90; G5 = 100; C1 = 40; C2 = 100. Conclusions: This in vitro study suggested that sodium hypochlorite-based substances and hydrogen peroxide are more efficient disinfectants against C. albicans than 2% chlorhexidine solution and the effervescent agent. PMID:19936521

  18. Synthesis of carboxymethylcellulose/acrylic acid hydrogels with superabsorbent properties by radiation-initiated crosslinking

    NASA Astrophysics Data System (ADS)

    Fekete, Tamás; Borsa, Judit; Takács, Erzsébet; Wojnárovits, László

    2016-07-01

    Superabsorbent hydrogels were prepared by gamma irradiation from aqueous solutions of carboxymethylcellulose (CMC) and acrylic acid (AAc) with varying CMC:AAc ratio. By partially replacing the CMC with AAc the gelation increased and led to a higher gel fraction and lower water uptake. Moreover, the gelation required significantly milder synthesis conditions. Decreasing both the dose and the solute concentration in the presence of AAc led to gels with higher gel fraction and higher degree of swelling compared to pure CMC gels. Increasing the AAc content up to 10% proved to be very effective, while very high AAc content (over 50%) hindered the gelation process.

  19. Effects of Sonication Conditions on Ultrasonic Dispersion of Inorganic Particles in Acrylic Resin

    NASA Astrophysics Data System (ADS)

    Tuziuti, Toru; Yasui, Kyuichi; Towata, Atsuya; Kato, Kazumi

    2011-07-01

    The effects of sonication conditions on the ultrasonic dispersion of titanium dioxide particles in acrylic resin are investigated. Pulsing operation at appropriate on-off duty cycles enables us to attain a particle size smaller than that at a continuous wave (CW) at the same net time of sonication between operations. It is useful that frequency-sweep operation attains almost the same particle size as that at CW, which can provide a constant dispersion of particles even if the resonant frequency used to effectively drive an ultrasonic transducer changes with liquid conditions, such as the temperature and acoustic impedance of a liquid.

  20. Lattice Dynamics of Colloidal Crystals During Photopolymerization of Acrylic Monomer Matrix

    NASA Technical Reports Server (NTRS)

    Sunkara, Hari B.; Benjamin, Penn G.; Donald, Frazier O.; Ramachandran, N.

    1997-01-01

    Polymerization process are the major contributors for observed lattice compression and lattice disorder of the Crystalline Colloidal Arrays (CCA) of silica spheres in polymerized acrylic/methacrylic ester films. The effect of orientation of photocell with respect to the readiation source on Bragg diffraction of CCA indicated the presence of convective stirring in thin fluid system during the photopolymerization that deleteriously affect the periodic array structures. To devise reproducible and more efficient optical filters, experimental methods to minimize or eliminate convective instabilities in monomeric dispersions during polymerization are suggested.

  1. Acrylic resin-fiber composite--Part I: The effect of fiber concentration on fracture resistance.

    PubMed

    Vallittu, P K; Lassila, V P; Lappalainen, R

    1994-06-01

    This study tested the effect on the fracture resistance of acrylic resin test specimens when different amounts of fibers were incorporated in the resin matrix. The fibers used included glass, carbon, and aramid fibers, with 30 test specimens of each concentration of fibers. Transverse sections of the specimens were studied by scanning electron microscope to establish how the fibers behave in the polymerization process. The results indicated that an increase in the amount of fibers enhanced the fracture resistance of the test specimens (p < 0.001). The SEM micrographs of transverse sections of test polymerized specimens revealed void spaces of different sizes inside the fiber roving. PMID:8040825

  2. Towards control of viscous effects in acrylic-based actuator applications

    NASA Astrophysics Data System (ADS)

    Thylander, S.; Menzel, A.; Ristinmaa, M.

    2016-09-01

    Dielectric elastomers offer clear advantages over more traditional and conventional materials when soft, lightweight, noiseless actuator applications with large deformations are considered. However, the viscous time-dependent behaviour associated with most elastomers limit the number of possible applications. For this purpose, the possibility of controlling the viscous response by regulating the applied electric potential is explored. The constitutive model chosen is calibrated to fit the electro-viscoelastic response of an acrylic elastomer often used in dielectric elastomer actuators. The response of both homogeneous deformation examples and inhomogeneous finite element boundary value problems, chosen to mimic existing applications, are presented. Control of both force and displacement quantities are successfully achieved.

  3. Facial Granulomas Secondary to Injection of Semi-Permanent Cosmetic Dermal Filler Containing Acrylic Hydrogel Particles

    PubMed Central

    Sachdev, Mukta; Anantheswar, YN; Ashok, BC; Hameed, Sunaina; Pai, Sanjay A

    2010-01-01

    Various reports of long-term complications with semi-permanent fillers, appearing several years after injections have created some concern about their long-term safety profile. We report a case of foreign body granuloma secondary to dermal filler containing a copolymer of the acrylic hydrogel particles, hydroxyethylmethacrylate and ethylmethacrylate, occurring 2 years after the injection. The foreign body granulomas could not be treated satisfactorily with intralesional steroids, and the patient required a surgical excision of her granulomas. The physical and psychological consequences to such patients can be quite devastating. PMID:21430829

  4. Antimicrobial effects of esters and amides of 3-(5-nitro-2-furyl)acrylic acid.

    PubMed

    Kellová, G; Sturdík, E; Stibrányi, L; Drobnica, L; Augustín, J

    1984-01-01

    The effect of 18 newly synthesized esters and amides of 3-(5-nitro-2-furyl)acrylic acid on bacteria (Escherichia coli, Staphylococcus aureus), yeasts (Saccharomyces cerevisiae, Candida albicans), molds (Aspergillus niger, Penicillium cyclopium, Rhizopus oryzae) and algae (Chlorella pyrenoidosa, Euglena gracilis, Scenedesmus obliquus) was investigated. The MIC values revealed antimycotic, antialgal and antibacterial activity of the studied derivatives. The antimycotic activity was found to decrease with increasing the length of the alkyl chain of esters and after introduction of amino nitrogen into the furylethylene backbone. The inhibitory effect on growth is caused by blocking bioenergetic processes, glycolysis in particular. PMID:6714854

  5. The Relationship Between Water Structure and Blood Compatibility in Poly(2-methoxyethyl Acrylate) (PMEA) Analogues.

    PubMed

    Sato, Kazuhiro; Kobayashi, Shingo; Kusakari, Miho; Watahiki, Shogo; Oikawa, Masahiko; Hoshiba, Takashi; Tanaka, Masaru

    2015-09-01

    Six types of poly(2-methoxyethyl acrylate) (PMEA) analogues were synthesized and the water structure in the hydrated polymers was characterized using differential scanning calorimetry (DSC). The hydrated PMEA analogues exhibited the different amounts of intermediate water. Non-thrombogenicity evaluation was performed on PMEA analogues for platelet adhesion and protein adsorption. Platelet adhesion was suppressed on PMEA analogues. In addition, the protein adsorption and deformation were suppressed by increasing the amount of intermediate water. This study demonstrates that the amount of intermediate water might play a key role in expressing the blood compatibility of polymeric materials. PMID:26017931

  6. Thermal destruction of copolymers of polypropylene glycol maleate with acrylic acid

    NASA Astrophysics Data System (ADS)

    Burkeev, M. Zh.; Sarsenbekova, A. Zh.; Tazhbaev, E. M.; Figurinene, I. V.

    2015-12-01

    The results from thermogravimetric and kinetic studies of copolymers of polypropylene glycol maleate with acrylic acid at different molar ratios are presented. The results from conventional thermogravimetric studies are used to determine kinetic characteristics of the process of thermal decomposition, i.e., activation energy and pre-exponential factors. These parameters are determined in three ways: the Achar, Freeman-Carroll, and Sharp-Wentworth methods. Activation energies calculated using all the three methods confirm the dependence of the destruction process on the ratio of components in a synthesized copolymer. It is shown that the obtained values of the activation energies and thermodynamic characteristics allow us to predict a copolymer's composition.

  7. Immobilization of penicillin acylase on copolymer of butyl acrylate and ethylene glycol dimethacrylate.

    PubMed

    Bryjak, J; Noworyta, A

    1993-01-01

    The effects of glutaraldehyde, enzyme concentrations and reactants volumes, ionic strength, pH value and carrier particle diameter on immobilization of penicillin acylase onto acrylic carriers were studied. The activity of immobilized enzyme preparations was also studied over a range of pH values and temperatures and thermal and pH stabilities were determined. The use of the immobilized preparation for penicillin G hydrolysis in a batch reactor was investigated. The immobilized enzyme gave a significant reduction in hydrolysis time compared to hydrolysis by the native enzyme. PMID:7763686

  8. Bioinspired bioadhesive polymers: dopa-modified poly(acrylic acid) derivatives.

    PubMed

    Laulicht, Bryan; Mancini, Alexis; Geman, Nathanael; Cho, Daniel; Estrellas, Kenneth; Furtado, Stacia; Hopson, Russell; Tripathi, Anubhav; Mathiowitz, Edith

    2012-11-01

    The one-step synthesis and characterization of novel bioinspired bioadhesive polymers that contain Dopa, implicated in the extremely adhesive byssal fibers of certain gastropods, is reported. The novel polymers consist of combinations of either of two polyanhydride backbones and one of three amino acids, phenylalanine, tyrosine, or Dopa, grafted as side chains. Dopa-grafted hydrophobic backbone polymers exhibit as much as 2.5 × the fracture strength and 2.8 × the tensile work of bioadhesion of a commercially available poly(acrylic acid) derivative as tested on live, excised, rat intestinal tissue. PMID:23008096

  9. Stabilization of mid-sized silicon nanoparticles by functionalization with acrylic acid

    NASA Astrophysics Data System (ADS)

    Bywalez, Robert; Karacuban, Hatice; Nienhaus, Hermann; Schulz, Christof; Wiggers, Hartmut

    2012-01-01

    We present an enhanced method to form stable dispersions of medium-sized silicon nanoparticles for solar cell applications by thermally induced grafting of acrylic acid to the nanoparticle surface. In order to confirm their covalent attachment on the silicon nanoparticles and to assess the quality of the functionalization, X-ray photoelectron spectroscopy and diffuse reflectance infrared Fourier spectroscopy measurements were carried out. The stability of the dispersion was elucidated by dynamic light scattering and Zeta-potential measurements, showing no sign of degradation for months.

  10. Liquid Crystal Alignment Effect on Photopolymer Surface Using an Acrylate Unit Photopolymerized by a Photoinitiator

    NASA Astrophysics Data System (ADS)

    Kim, Jun-Young; Hwang, Jeoung-Yeon; Kim, Tae-Ho; Seo, Dae-Shik; Lee, Joon-Ung

    2003-01-01

    Photoalignment materials of PGMAcr, poly[3-(acryloyloxy)-2-hydroxypropyl methacrylate] using an acrylate unit photopolymerized by a photo-initiator and PGMA4Ch, poly[3-(4-chalconyloxy)-2-hydroxypropyl methacrylate] using photodimerization by the chalcone group were synthesized. Also, the liquid crystal (LC) alignment capabilities on the photopolymer layers were studied. A good LC alignment with UV exposure on the PGMAcr surface can be obtained. However, LC alignment defects were observed on the PGMA4Ch surface. The LC alignment capability of the PGMAcr surface by the photoinitiator was better than that of the PGMA4Ch surface by the chalcone group which is a photosensitive moiety.

  11. Shaped, lead-loaded acrylic filters for patient exposure reduction and image-quality improvement

    SciTech Connect

    Gray, J.E.; Stears, J.G.; Frank, E.D.

    1983-03-01

    Shaped filters that are constructed of lead-loaded acrylic material for use in patient radiography are discussed. Use of the filters will result in improved overall image quality with significant exposure reduction to the patient (approximately a 2X reduction in breast exposure and a 3X reduction in thyroid gland exposure). Detailed drawings of the shaped filters for scoliosis radiography, cervical spine radiography, and for long film changers in special procedures are provided. The use of the scoliosis filters is detailed and includes phantom and patient radiographs and dose reduction information.

  12. Pharmacokinetics of copolymers of N-vinylpyrrolidone with acrylic acid. Article 1

    SciTech Connect

    Rafikov, R.Z.; Sakhibov, A.D.; Akhmedzhanov, R.I.; Aliev, K.U.

    1987-01-01

    The authors studied the pharmacokinetics of the copolymers of n-vinyl-pyrrolidone (I) with acrylic acid (II) (copolymer III) using the radioactive isotope /sup 125/I. In experiments on mice, they studied the distribution of a copolymer of I with II (/sup 125/I-III) in the organism of the animals. The content of /sup 125/I-III and its possible radioactive metabolites in the blood and organs of mice after a single intravenous administration of the given preparation is shown. The radioactivity of organs after butanol extraction is presented.

  13. Characterization of acrylic resins used for restoration of artworks by pyrolysis-silylation-gas chromatography/mass spectrometry with hexamethyldisilazane.

    PubMed

    Osete-Cortina, Laura; Doménech-Carbó, María Teresa

    2006-09-15

    A procedure based on the technique of the pyrolysis-GC/MS has been applied, in this work, in order to determine the composition of synthetic acrylic resins employed in artworks. The method is based on the on line derivatization of these resins using hexamethyldisilazane (HMDS). Results obtained have been compared with those others from direct pyrolysis and in situ thermally assisted hydrolysis and methylation with tetramethylammonium hydroxide (TMAH). Sensitivity using HMDS as derivatising reagent is found similar to that from direct pyrolysis and methylation with TMAH. Better resolution of the most representative peaks has been also obtained. Additionally, this method reduces the formation of free acrylic acid molecules during the pyrolysis process and, in consequence, more simplified and well-resolved chromatograms are obtained. Finally, the reported procedure has been successfully used for characterizing several acrylic-based varnishes and binding media currently used in Fine Arts and real pictorial samples from graffiti performed on a Middle Ages bridge. PMID:16797558

  14. Decolourization performance in C. I. Vat Yellow 1 aqueous suspension using hydrophobically modified poly(acrylic acid).

    PubMed

    Chen, J; Chen, M C

    2011-01-01

    A series of hydrophobically modified poly(acrylic acid) (PAA), poly(2-phenoxyethyl acrylate-co-acrylic acid) (poly(PHEA-co-AA)), have been synthesized and characterized by Ubbelohde type viscometry, Nuclear Magnetic Resonance (1H NMR) spectrometry and Differential Scanning Calorimetry (DSC). The shear thinning Non-Newtonian fluid behavior of their aqueous solution and the dependence on pH and hydrophobic group contents were found through apparent viscosity and rheological property investigating. Decolourization performance in C. I. Vat Yellow 1 aqueous suspension was evaluated through visible absorbance data. Decolourization performance of hydrophobically associated polymer indicates two times better than that of PAA. The quantitative relationship was mainly studied. PMID:21866762

  15. Poly(acrylic acid) to induce competitive crystallization of a theophylline/oxalic acid cocrystal and a theophylline polymorph

    NASA Astrophysics Data System (ADS)

    Jang, Jisun; Kim, Il Won

    2016-01-01

    Polymeric additives to induce competitive crystallization of pharmaceutical compounds were explored. A cocrystal of theophylline and oxalic acid was used as a model system, and poly(acrylic acid), poly(caprolactone), and poly(ethylene glycol) were the additives. The cocrystal formation was selectively hindered with addition of poly(acrylic acid). First the size of the cocrystals were reduced, and eventually the cocrystallization was inhibited to generate neat theophylline crystals. The theophylline crystals were of a distinctively different crystal structure from known polymorphs, based on powder X-ray diffraction. They were also obtained in nanoscale size, when millimeter-scale crystals formed without poly(acrylic acid). Polymeric additives that could form specific interactions with crystallizing compounds seem to be useful tools for the phase and size control of pharmaceutical crystals.

  16. A technique to splint and verify the accuracy of implant impression copings with light-polymerizing acrylic resin.

    PubMed

    Rutkunas, Vygandas; Ignatovic, Jevgenija

    2014-03-01

    Transferring the implant position from the mouth to the definitive cast is one of the most critical steps in implant prosthodontics. To achieve a passive fit of the prosthesis, an accurate implant impression is crucial because discrepancies can induce both biologic and technical complications. Analysis of available research data suggests that a direct (pick-up) impression technique with splinted copings is the technique of choice, particularly for multiple implants. However, the traditional method of splinting the copings with autopolymerizing acrylic resin is a technique-sensitive and time- consuming procedure. This report describes a straightforward method of splinting impression copings with light-polymerizing acrylic resin, with minimal amount of autopolymerizing acrylic resin. The method also can be used to verify splinting accuracy. PMID:24445030

  17. Aquatic toxicity of acrylates and methacrylates: quantitative structure-activity relationships based on Kow and LC50

    SciTech Connect

    Reinert, K.H.

    1987-12-01

    Recent EPA scrutiny of acrylate and methacrylate monomers has resulted in restrictive consent orders and Significant New Use Rules under the Toxic Substances Control Act, based on structure-activity relationships using mouse skin painting studies. The concern is centered on human health issues regarding worker and consumer exposure. Environmental issues, such as aquatic toxicity, are still of concern. Understanding the relationships and environmental risks to aquatic organisms may improve the understanding of the potential risks to human health. This study evaluates the quantitative structure-activity relationships from measured log Kow's and log LC50's for Pimephales promelas (fathead minnow) and Carassius auratus (goldfish). Scientific support of the current regulations is also addressed. Two monomer classes were designated: acrylates and methacrylates. Spearman rank correlation and linear regression were run. Based on this study, an ecotoxicological difference exists between acrylates and methacrylates. Regulatory activities and scientific study should reflect this difference.

  18. Multielement crystalline and pseudocrystalline oxides as efficient catalysts for the direct transformation of glycerol into acrylic acid.

    PubMed

    Chieregato, Alessandro; Soriano, M Dolores; García-González, Ester; Puglia, Giuseppe; Basile, Francesco; Concepción, Patricia; Bandinelli, Claudia; López Nieto, José M; Cavani, Fabrizio

    2015-01-01

    Glycerol surplus from biodiesel synthesis still represents a major problem in the biofuel production chain. Meanwhile, those in the acrylic acid market are looking for new processes that are able to offer viable alternatives to propylene-based production. Therefore, acrylic acid synthesis from glycerol could be an effective solution to both issues. Among the viable routes, one-pot synthesis theoretically represents the most efficient process, but it is also highly challenging from the catalyst design standpoint. A new class of complex W--Mo--V mixed-oxide catalysts, which are strongly related to the hexagonal tungsten bronze structure, able to directly convert glycerol into acrylic acid with yields of up to 51 % are reported. PMID:25488515

  19. Effects of crosslinking, prestrain, and dielectric filler on the electromechanical response of a new silicone and comparison with acrylic elastomer

    NASA Astrophysics Data System (ADS)

    Zhang, Xuequn; Wissler, M.; Jaehne, B.; Breonnimann, Rolf; Kovacs, Gabor

    2004-07-01

    Silicone and acrylic elastomers have received increased attention as dielectric electroactive polymer (EAP) materials for actuator technology. The goal of this work was to develop and characterize a new class of silicones (DC3481) and to compare it with acrylic elastomers. The influence of various types of hardeners, hardener concentration, prestrain and high dielectric organic fillers was studied by mechanical, electrical and electromechanical experiments. Furthermore the temperature dependence and the viscoelastic properties were investigated. The results show that by changing type and concentration of hardener, the Young's modulus can be varied. In order to increase the dielectric constant, the silicone was blended with organic materials. Compared to acrylic elastomers, this new class of silicone elastomers has the advantage of a constant stiffness over a wide range of temperature and a lower viscosity that results in a higher response speed of the actuator.

  20. A silver bullet: elemental silver as an efficient reducing agent for atom transfer radical polymerization of acrylates.

    PubMed

    Williams, Valerie A; Ribelli, Thomas G; Chmielarz, Pawel; Park, Sangwoo; Matyjaszewski, Krzysztof

    2015-02-01

    Elemental silver was used as a reducing agent in the atom transfer radical polymerization (ATRP) of acrylates. Silver wire, in conjunction with a CuBr(2)/TPMA catalyst, enabled the controlled, rapid preparation of polyacrylates with dispersity values down to Đ = 1.03. The silver wire in these reactions was reused several times in sequential reactions without a decline in performance, and the amount of copper catalyst used was reduced to 10 ppm without a large decrease in control. A poly(n-butyl acrylate)-block-poly(tert-butyl acrylate) diblock copolymer was synthesized with a molecular weight of 91 400 and Đ = 1.04, demonstrating good retention of chain-end functionality and a high degree of livingness in this ATRP system. PMID:25599253

  1. Corrosion Inhibitive Evaluation of an Environmentally Friendly Water-Base Acrylic Terpolymer on Mild Steel in Hydrochloric Acid Media

    NASA Astrophysics Data System (ADS)

    Azghandi, Mojtaba Vakili; Davoodi, Ali; Farzi, Gholam Ali; Kosari, Ali

    2013-12-01

    The corrosion inhibitive performance of an environmentally friendly water-base acrylic terpolymer [methyl methacrylate/Butyl Acrylate/Acrylic acid (ATP)] on mild steel in 1 M HCl was investigated by alternating current and direct current electrochemical techniques and the quantum chemical method. An efficiency of more than 97 pct was obtained with 0.8 mmol/L ATP. The increase in inhibitor concentration and immersion time has a positive effect, while the temperature influence is negligible on the inhibitor efficiency. The present terpolymer obeys the Langmuir isotherm, and thermodynamic calculation reveals a chemisorption type on the surface. Density functional calculations showed that the lone pairs of electrons of oxygen in the structure of three monomers are suitable sites to adsorb onto the metal surface. Finally, in the presence of ATP, a decrease in surface roughness and corrosion attacks was demonstrated by atomic force microscopy and optical microscopy examinations, respectively.

  2. Radiation-curing of acrylate composites including carbon fibres: A customized surface modification for improving mechanical performances

    NASA Astrophysics Data System (ADS)

    Martin, Arnaud; Pietras-Ozga, Dorota; Ponsaud, Philippe; Kowandy, Christelle; Barczak, Mariusz; Defoort, Brigitte; Coqueret, Xavier

    2014-12-01

    The lower transverse mechanical properties of radiation-cured acrylate-based composites reinforced with carbon-fibre with respect to the thermosettable analogues was investigated from the viewpoint of chemical interactions at the interface between the matrix and the carbon material. XPS analysis of representative commercial carbon fibres revealed the presence of a significant amount of chemical functions potentially exerting an adverse effect on the initiation and propagation of the free radical polymerization initiated under high energy radiation. The EB-induced polymerization of n-butyl acrylate as a simple model monomer was conducted in the presence of various aromatic additives exhibiting a strong inhibiting effect, whereas thiols efficiently sensitize the initiation mechanism and undergo transfer reactions. A method based on the surface modification of sized fibres by thiomalic acid is proposed for overcoming the localized inhibition phenomenon and for improving the mechanical properties of the resulting acrylate-based composites.

  3. Metabolic and thermoregulatory responses of the rat maintained in acrylic or wire-screen cages: implications for pharmacological studies.

    PubMed

    Gordon, C J; Fogelson, L

    1994-07-01

    Because of differences in thermal conductivity, it is likely that a rodent's thermoregulatory requirements and their response to drugs and other stimuli will vary in metal and acrylic cages. To address these issues, thermoregulatory responses were measured in rats housed in an environmental chamber with a floor made of either solid metal (aluminum) or acrylic materials (Plexiglas). Metabolic rate (M), evaporative water loss (E), thermal conductance (C), and tail skin (Tsk) and core temperature (Tc) were measured at ambient temperatures (Ta) of 10, 20, 28, 30, 32, and 34 degrees C. These thermoregulatory variables were essentially unaffected by floor type at Tas of 20 and 28 degrees C. The acrylic floor showed greater increases in M, E, Tc, and Tsk, but a smaller elevation in C as Ta increased from 28 to 34 degrees C. At a Ta of 10 degrees C, rats on the acrylic floor had a smaller M compared to that measured on the metal floor. Rats were then injected with saline or 30 mg/kg (SC) of 3,4-methylenedioxymethamphetamine (MDMA) and placed in an acrylic cage with wood chip bedding or a wire-screen cage at a Ta of 20 degrees C. The MDMA caused Tc to increase > 2.0 degrees C in rats in the acrylic cage but had no effect on Tc of rats in the wire-screen cage. The marked effect of cage type on basal thermoregulatory processes and thermogenic response to MDMA should be useful in the design and interpretation of many pharmacological studies. PMID:7916156

  4. pH- and Electro-Responsive Properties of Poly(acrylic acid) and Poly(acrylic acid)-block-poly(acrylic acid-grad-styrene) Brushes Studied by Quartz Crystal Microbalance with Dissipation Monitoring.

    PubMed

    Borisova, O V; Billon, L; Richter, R P; Reimhult, E; Borisov, O V

    2015-07-14

    We report on the synthesis of novel pH- and electro-responsive polyelectrolyte brushes from a gold substrate by direct one-step nitroxide-mediated polymerization of acrylic acid (AA) or copolymerization of AA and styrene (S). In the latter case, amphiphilic brushes of block-gradient copolymers PAA-b-(PAA-grad-PS) comprising one PAA block and one block with the gradient sequence of AA and S were obtained. The block-gradient copolymers are initiated from the surface by the start of the PAA block. The brushes were characterized by XPS and ellipsometry. (1)H NMR confirmed the gradient sequence of the PAA-grad-PS copolymer block. The pH- and electro-responsive properties of the brushes were studied by quartz crystal microbalance with dissipation monitoring (QCM-D) in combination with electrochemistry. This method provides evidence of swelling of the PAA brushes proportional to the contour length of the chains at elevated pH, whereas the response functions of the block-gradient copolymers are more complex and point to intermolecular aggregation in the brush at low pH. Monitoring of the changes in resonance frequency and dissipation of the QCM-D also demonstrates that application of negative voltage to the substrate leads to swelling of the brush; application of a positive voltage provokes only a transient collapse of the brush in proportion to the applied voltage. PMID:26070329

  5. Junction-Controlled Elasticity of Single-Walled Carbon Nanotube Dispersions in Acrylic Copolymer Gels and Solutions

    SciTech Connect

    Schoch, Andrew B.; Shull, Kenneth R.; Brinson, L. Catherine

    2008-08-26

    Oscillatory shear rheometry is used to study the mechanical response of single-walled carbon nanotubes dispersed in solutions of acrylic diblock or triblock copolymers in 2-ethyl-1-hexanol. Thermal transitions in the copolymer solutions provide a route for the easy processing of these composite materials, with excellent dispersion of the nanotubes as verified by near-infrared photoluminescence spectroscopy. The nanotube dispersions form elastic networks with properties that are controlled by the junction points between nanotubes, featuring a temperature-dependent elastic response that is controlled by the dynamic properties of the matrix copolymer solution. The data are consistent with the formation of micelle-like aggregates around the nanotubes. At low temperatures the core-forming poly(methyl methacrylate) blocks are glassy, and the overall mechanical response of the composite does not evolve with time. At higher temperatures the enhanced mobility of the core-forming blocks enables the junctions to achieve more intimate nanotube-nanotube contact, and the composite modulus increases with time. These aging effects are observed in both diblock and triblock copolymer solutions but are partially reversed in the triblock solutions by cooling through the gel transition of the triblock copolymer. This result is attributed to the generation of internal stresses during gelation and the ability of these stresses to break or weaken the nanotube junctions.

  6. Acrylate metathesis via the second-generation Grubbs catalyst: unexpected pathways enabled by a PCy3-generated enolate.

    PubMed

    Bailey, Gwendolyn A; Fogg, Deryn E

    2015-06-17

    The diverse applications of acrylate metathesis range from synthesis of high-value α,β-unsaturated esters to depolymerization of unsaturated polymers. Examined here are unexpected side reactions promoted by the important Grubbs catalyst GII. Evidence is presented for attack of PCy3 on the acrylate olefin to generate a reactive carbanion, which participates in multiple pathways, including further Michael addition, proton abstraction, and catalyst deactivation. Related chemistry may be anticipated whenever labile metal-phosphine complexes are used to catalyze reactions of substrates bearing an electron-deficient olefin. PMID:26030596

  7. Evaluation of shrinkage polymerization and temperature of different acrylic resins used to splinting transfer copings in indirect impression technique

    NASA Astrophysics Data System (ADS)

    Franco, Ana Paula G. O.; Karam, Leandro Z.; Galvão, José R.; Kalinowski, Hypolito J.

    2015-09-01

    The aim of the present study was evaluate the shrinkage polymerization and temperature of different acrylic resins used to splinting transfer copings in indirect impression technique. Two implants were placed in an artificial bone, with the two transfer copings joined with dental floss and acrylic resins; two dental resins are used. Measurements of deformation and temperature were performed with Fiber Braggs grating sensor for 17 minutes. The results revealed that one type of resin shows greater values of polymerization shrinkage than the other. Pattern resins did not present lower values of shrinkage, as usually reported by the manufacturer.

  8. Screening of Metagenomic and Genomic Libraries Reveals Three Classes of Bacterial Enzymes That Overcome the Toxicity of Acrylate

    PubMed Central

    Curson, Andrew R. J.; Burns, Oliver J.; Voget, Sonja; Daniel, Rolf; Todd, Jonathan D.; McInnis, Kathryn; Wexler, Margaret; Johnston, Andrew W. B.

    2014-01-01

    Acrylate is produced in significant quantities through the microbial cleavage of the highly abundant marine osmoprotectant dimethylsulfoniopropionate, an important process in the marine sulfur cycle. Acrylate can inhibit bacterial growth, likely through its conversion to the highly toxic molecule acrylyl-CoA. Previous work identified an acrylyl-CoA reductase, encoded by the gene acuI, as being important for conferring on bacteria the ability to grow in the presence of acrylate. However, some bacteria lack acuI, and, conversely, many bacteria that may not encounter acrylate in their regular environments do contain this gene. We therefore sought to identify new genes that might confer tolerance to acrylate. To do this, we used functional screening of metagenomic and genomic libraries to identify novel genes that corrected an E. coli mutant that was defective in acuI, and was therefore hyper-sensitive to acrylate. The metagenomic libraries yielded two types of genes that overcame this toxicity. The majority encoded enzymes resembling AcuI, but with significant sequence divergence among each other and previously ratified AcuI enzymes. One other metagenomic gene, arkA, had very close relatives in Bacillus and related bacteria, and is predicted to encode an enoyl-acyl carrier protein reductase, in the same family as FabK, which catalyses the final step in fatty-acid biosynthesis in some pathogenic Firmicute bacteria. A genomic library of Novosphingobium, a metabolically versatile alphaproteobacterium that lacks both acuI and arkA, yielded vutD and vutE, two genes that, together, conferred acrylate resistance. These encode sequential steps in the oxidative catabolism of valine in a pathway in which, significantly, methacrylyl-CoA is a toxic intermediate. These findings expand the range of bacteria for which the acuI gene encodes a functional acrylyl-CoA reductase, and also identify novel enzymes that can similarly function in conferring acrylate resistance, likely, again

  9. Comparative Evaluation of Effect of Water Absorption on the Surface Properties of Heat Cure Acrylic: An in vitro Study

    PubMed Central

    Chandu, G S; Asnani, Pooja; Gupta, Siddarth; Faisal Khan, Mohd.

    2015-01-01

    Background: Use of alkaline peroxide denture cleanser with different temperature of water could cause a change in surface hardness of the acrylic denture and also has a bleaching effect. The purpose of the study was to determine the effect of increased water content during thermal cycling of hot water-treated acrylic on the surface hardness of acrylic denture base when compared to warm water treated acrylic. And to compare the bleaching effect of alkaline peroxide solution on the acrylic denture base on hot water and warm water treated acrylic. Materials and Methods: Forty samples (10 mm × 10 mm × 2.5 mm) were prepared. After the calculation of the initial hardness 40 samples, each was randomly assigned to two groups. Group A: 20 samples were immersed in 250 ml of warm distilled water at 40°C with alkaline peroxide tablet. Group B: 20 samples were immersed in 250 ml of hot distilled water at 100°C with alkaline peroxide tablet. The surface hardness of each test sample was obtained using the digital hardness testing machine recording the Rockwell hardness number before the beginning of the soaking cycles and after completion of 30 soak cycles and compared. Values were analyzed using paired t-test. Five samples from the Group A and five samples from Group B were put side by side and photographed using a Nikon D 40 digital SLR Camera and the photographs were examined visually to assess the change in color. Results: Acrylic samples immersed in hot water showed a statistically significant decrease of 5.8% in surface hardness. And those immersed in warm water showed a statistically insignificant increase of 0.67% in surface hardness. Samples from the two groups showed clinically insignificant difference in color when compared to each other on examination of the photographs. Conclusion: Thermocycling of the acrylic resin at different water bath temperature at 40°C and 100°C showed significant changes in the surface hardness. PMID:25954074

  10. Topological characterization of a bacterial cellulose-acrylic acid polymeric matrix.

    PubMed

    Halib, N; Mohd Amin, M C I; Ahmad, I; Abrami, M; Fiorentino, S; Farra, R; Grassi, G; Musiani, F; Lapasin, R; Grassi, M

    2014-10-01

    This paper focuses on the micro- and nano-topological organization of a hydrogel, constituted by a mixture of bacterial cellulose and acrylic acid, and intended for biomedical applications. The presence of acrylic acid promotes the formation of two interpenetrated continuous phases: the primary "pores phase" (PP) containing only water and the secondary "polymeric network phase" (PNP) constituted by the polymeric network swollen by the water. Low field Nuclear Magnetic Resonance (LF NMR), rheology, Scanning Electron Microscopy (SEM) and release tests were used to determine the characteristics of the two phases. In particular, we found that this system is a strong hydrogel constituted by 81% (v/v) of PP phase the remaining part being occupied by the PNP phase. Pores diameters span in the range 10-100 μm, the majority of them (85%) falling in the range 30-90 μm. The high PP phase tortuosity indicates that big pores are not directly connected to each other, but their connection is realized by a series of interconnected small pores that rend the drug path tortuous. The PNP is characterized by a polymer volume fraction around 0.73 while mesh size is around 3 nm. The theoretical interpretation of the experimental data coming from the techniques panel adopted, yielded to the micro- and nano-organization of our hydrogel. PMID:24932712

  11. Olfactory function in chemical workers exposed to acrylate and methacrylate vapors

    SciTech Connect

    Schwartz, B.S.; Doty, R.L.; Frye, R. ); Monroe, C.; Barker, S. )

    1989-05-01

    An investigation of the olfactory function of 731 workers at a chemical facility which manufactures acrylates and methacrylates was undertaken using a standardized quantitative test. In a cross-section analysis of the data, no associations of chemical exposure with olfactory test scores were observed. A nested case-control study designed to evaluate the cumulative effects of exposure on olfactory function, however, revealed elevated crude exposure odds ratios of 2.0 (1.1, 3.8) for all workers and 6.0 (1.7, 21.5) for workers who never smoked cigarettes. Logistic regression analysis, adjusting for multiple confounders, revealed exposure odds ratios of 2.8 (1.1, 7.0) and 13.5 (2.1, 87.6) in these same groups, respectively, and a dose-response relationship between olfactory dysfunction and cumulative exposure scores - semi-quantitative indices of lifetime exposure to the acrylates. The data also revealed decreasing exposure odds ratios with increasing duration since last exposure to these chemicals, suggesting that the effects may be reversible.

  12. Multi-walled carbon nanotubes/polymer composites in absence and presence of acrylic elastomer (ACM).

    PubMed

    Kumar, S; Rath, T; Mahaling, R N; Mukherjee, M; Khatua, B B; Das, C K

    2009-05-01

    Polyetherimide/Multiwall carbon nanotube (MWNTs) nanocomposites containing as-received and modified (COOH-MWNT) carbon nanotubes were prepared through melt process in extruder and then compression molded. Thermal properties of the composites were characterized by thermo-gravimetric analysis (TGA). Field emission scanning electron microscopy (FESEM) images showed that the MWNTs were well dispersed and formed an intimate contact with the polymer matrix without any agglomeration. However the incorporation of modified carbon nanotubes formed fascinating, highly crosslinked, and compact network structure throughout the polymer matrix. This showed the increased adhesion of PEI with modified MWNTs. Scanning electron microscopy (SEM) also showed high degree of dispersion of modified MWNTs along with broken ends. Dynamic mechanical analysis (DMA) results showed a marginal increase in storage modulus (E') and glass transition temperature (T(g)) with the addition of MWNTs. Increase in tensile strength and impact strength of composites confirmed the use the MWNTs as possible reinforcement agent. Both thermal and electrical conductivity of composites increased, but effect is more pronounced on modification due to formation of network of carbon nanotubes. Addition of acrylic elastomer to developed PEI/MWNTs (modified) nanocomposites resulted in the further increase in thermal and electrical properties due to the formation of additional bond between MWNTs and acrylic elastomers at the interface. All the results presented are well corroborated by SEM and FESEM studies. PMID:19452959

  13. Acrylic coatings exhibiting improved hardness, solvent resistance and glossiness by using silica nano-composites

    NASA Astrophysics Data System (ADS)

    Dashtizadeh, Ahmad; Abdouss, Majid; Mahdavi, Hossein; Khorassani, Manuchehr

    2011-01-01

    To prepare nano-composite emulsion acrylic resins with improved surface hardness and solvent resistance, nano-silica particles were treated with surfactants. The monomers of methyl methacrylate/butylacrylate were co-polymerized on the surface of dispersed silica particles. Several emulsions with different silica contents and copolymer mole fractions were prepared. Finally the emulsions were modified to water-based acrylic coatings and improved properties such as surface hardness, solvent resistance and glossiness were determined. The study of coatings was directed to find the improved resin by optimum surface properties. Size distribution and morphology of latexes were characterized by Fourier transform infrared spectroscopy, dynamic light scattering, transmission electron microscopy and scanning electron microscopy. The glass transition temperature of nano-composites was measured and discussed its relation with silica contents, monomer mole fractions and improved properties of coatings. The optimum pendulum hardness of coatings was on 0.46 methyl methacrylate mole fraction and 120 g silica content. An increase in pendulum hardness of nano-composites with the addition of modified silica was observed. DLS and TEM studies indicate that silica particles were dispersed homogenously through the polymer matrix.

  14. Electrocoagulation pretreatment of wet-spun acrylic fibers manufacturing wastewater to improve its biodegradability.

    PubMed

    Gong, Chenhao; Zhang, Zhongguo; Li, Haitao; Li, Duo; Wu, Baichun; Sun, Yuwei; Cheng, Yanjun

    2014-06-15

    The electrocoagulation (EC) process was used to pretreat wastewater from the manufacture of wet-spun acrylic fibers, and the effects of varying the operating parameters, including the electrode area/wastewater volume (A/V) ratio, current density, interelectrode distance and pH, on the EC treatment process were investigated. About 44% of the total organic carbon was removed using the optimal conditions in a 100 min procedure. The optimal conditions were a current density of 35.7 mA cm(-2), an A/V ratio of 0.28 cm(-1), a pH of 5, and an interelectrode distance of 0.8 cm. The biodegradability of the contaminants in the treated water was improved by the EC treatment (using the optimal conditions), increasing the five-day biological oxygen demand/chemical oxygen demand ratio to 0.35, which could improve the effectiveness of subsequent biological treatments. The improvement in the biodegradability of the contaminants in the wastewater was attributed to the removal and degradation of aromatic organic compounds, straight-chain paraffins, and other organic compounds, which we identified using gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy. The EC process was proven to be an effective alternative pretreatment for wastewater from the manufacture of wet-spun acrylic fibers, prior to biological treatments. PMID:24813666

  15. Improving bone cement toughness and contrast agent confinement by using acrylic branched polymers.

    PubMed

    Lissarrague, Maria H; Fascio, Mirta L; Goyanes, Silvia; D'Accorso, Norma B

    2016-02-01

    A new biomedical material to be used as part of acrylic bone cement formulations is described. This new material is tough, its Young's Modulus is similar to the one of poly (methylmethacrylate) and the contrast agent, usually employed in acrylic bone cements, is homogeneously distributed among the polymeric matrix. Additionally, its wear coefficient is 66% lower than the one measured in poly(methyl methacrylate). The developed material is a branched polymer with polyisoprene backbone and poly(methyl methacrylate) side chains, which are capable of retaining barium sulphate nanoparticles thus avoiding their aggregation. The grafting reaction was carried out in presence of the nanoparticles, using methyl methacrylate as solvent. From the (1)H-NMR spectra it was possible to determine the average number of MMA units per unit of isoprene (3.75:1). The ability to retain nanoparticles (about 8wt.%), attributed to their interaction with the polymer branches, was determined by thermogravimetric analysis and confirmed by FTIR and microscopy techniques. By SEM microscopy it was also possible to determine the homogeneous spatial distribution of the barium sulphate nanoparticles along the polymer matrix. PMID:26652446

  16. Controlled release of anti-diabetic drug Gliclazide from poly(caprolactone)/poly(acrylic acid) hydrogels.

    PubMed

    Bajpai, S K; Chand, Navin; Soni, Shweta

    2015-01-01

    Drug Gliclazide (Glz) has limited solubility and low bioavailability. In order to obtain a controlled release of this drug and to improve its bioavailability, the drug has been loaded into poly(caprolactone) (PCL)/poly(acrylic acid) (PAAc) hydrogels, prepared by free radical polymerization of acrylic acid in the presence of poly(caprolactone) in acetone medium using azo-isobutyronitrile as initiator and N,N' methylene bisacrylamide as cross-linking agent. The swelling behaviour of these hydrogels has been investigated in the physiological gastric and intestinal fluids to obtain an optimum composition suitable for delivery of a biologically active compound. The gels were loaded with anti-diabetic drug Glz and a detailed investigation of release of drug has been carried out. Various kinetic models have been applied on the release data. Finally, the Albino wistar rats were treated for Streptozotocin plus nicotinamide - induced diabetes using a Glz-loaded PCL/PAAc hydrogel. The results indicated a fair reduction in the glucose level of rats. PMID:26135033

  17. Detection of Defects in Acrylic and Steel Inclusions in Gypsum Using Compton Backscattered Gamma Rays

    NASA Astrophysics Data System (ADS)

    Boldo, Emerson M.; Appoloni, Carlos R.

    2011-08-01

    Compton scattering of gamma radiation is a nondestructive technique used for the detection of defects and inclusions in materials. The methodology allows one-side inspection of large structures, is relatively inexpensive and can be portable. The number of photons inelastically scattered within a well-defined volume element is linearly proportional to the electron density of the material. Targeting a sample with a collimated beam of gamma rays, the energy spectrum of backscattered photons can be used to determine local density perturbations. In this work we used the Compton backscattering technique to detection of small collinear defects in acrylic blocks and steel rods inclusions in gypsum blocks samples. The samples were irradiated with gamma rays from a O/2 mm collimated 241Am (100 mCi) source and the inelastically scattered photons were collected at an angle of 135° by a CdTe detector with a O/7 mm×30 mm collimation. Scanning was achieved by lateral movement of the sample blocks across the source and detector field of view in steps of 1 mm. The results showed that defects in the acrylic samples as small as 3 mm in size were visible in the intensity versus energy spectrum. The tests on gypsum blocks with steel rods inclusions suggest that, for a low energy and activity source, the effects of beam attenuation are more decisive to the scattered intensity than increasing of material density. An analysis of the density contrast is also presented.

  18. Tackiness of acrylic and cellulosic polymer films used in the coating of solid dosage forms.

    PubMed

    Wesseling, M; Kuppler, F; Bodmeier, R

    1999-01-01

    The objective was to determine the tackiness of acrylic and cellulosic polymer films in order to make predictions on the tackiness (agglomeration) of coated dosage forms during coating and curing. Force-displacement curves of the detachment process of two polymeric films were used as a measure of tackiness. Various polymers (cellulosic (Aquacoat and acrylics (Eudragit RS 30D, L 30D, NE 30D)), plasticizers (triacetin, triethyl citrate, tributyl citrate, acetyltributyl citrate) and anti-tacking agents (talc and glyceryl monostearate) were investigated. The order of tackiness for films prepared from the different aqueous polymer dispersions was in order of Eudragit NE 30D > RS 30D > RL 30D > Aquacoat. The tackiness increased with increasing plasticizer concentration due to the softening of the polymer. A correlation between the minimum film formation temperature and the tackiness was observed, however, no correlation between the tackiness and the lipophilicity of the plasticizer was seen. Talc and glyceryl monostearate (GMS) reduced the tackiness of the films significantly, with GMS being effective at much lower concentrations. Curing of Eudragit RS 30D-coated theophylline beads at temperatures higher than 40 degrees C in an irreversible agglomeration of the beads and damage of the coating upon separation of the beads. This resulted in a faster release than with uncured beads. Blending the beads with talc just prior to the curing step eliminated the agglomeration and therefore film damage, even at a curing temperature of 60 degrees C. PMID:10234529

  19. Protein absorption and fouling on poly(acrylic acid)-graft-polypropylene microfiltration membrane

    NASA Astrophysics Data System (ADS)

    Liu, Yanjun; Ma, Huiying; Lv, Chunying; Yang, Jia; Fu, Xueqi

    2009-07-01

    A series of pH-sensitive poly (acrylic acid)-graft-polypropylene hollow fiber microfiltration membranes were prepared by UV-photo-irradiation. Bovine serum albumin (BSA) was chosen as the model protein to investigate its absorption and fouling behaviors on membranes. The results showed that the hydrophilicity of grafted membrane was improved by poly(acrylic acid) chains with parts of membrane pores blocked. The grafted membranes were markedly pH-dependent on the water permeability as pH was altered from 1 to 11. The zeta potential of grafted membranes calculated by streaming potential was negative in most pH range. Electrostatic interaction energy calculated by DLVO theory showed the electric interaction force between grafted membrane and BSA was attractive. With the rise of grafting degree, the electric attractive force between grafted membrane and BSA increased as pH=3 and decreased as pH=8, while it kept basically unchanged as pH=4.7. As a result, most serious fouling was observed as pH=4.7. Grafted membranes had a lower BSA absorption and better antifouling behavior as pH=8, while the opposite result was revealed as pH=3. In conclusion, the absorption and fouling behavior of BSA on membranes was pH-dependent due to the pH-dependence of membrane charge, and the conformation of BSA and grafting chains.

  20. Effects of amylose content on property and microstructure of starch-graft-sodium acrylate copolymers.

    PubMed

    Zhang, Zhi; Chen, Peirong; Du, Xianfeng; Xue, Zhonghua; Chen, Shanshan; Yang, Baojun

    2014-02-15

    Starch-graft-sodium acrylate (St-g-SA) copolymers were synthesized with ammonium persulfate as an initiator. This work focused on the effects of amylose content of corn starch on the water absorbent capacity and microstructure of the St-g-SA copolymers. The water absorbent capacity of waxy, maize and high amylose St-g-SA copolymers was 1800 g/g, 1300 g/g and 1100 g/g respectively. The grafted copolymers were characterized by FTIR and solid state (13)C NMR confirming that the graft reaction had taken place between sodium acrylate and corn starch. The surfaces and cross sections of St-g-SA copolymers were observed by SEM. Incomplete gelatinized starch aggregates increased with increasing amylose content on surfaces and cross sections of copolymers, which accorded with the water absorbent capacity and grafting ratio. DMTA results showed that the waxy St-g-SA copolymer had the highest transition temperature which indicated waxy starch had high grafting ratio. PMID:24507305

  1. Microbubble enhanced ozonation process for advanced treatment of wastewater produced in acrylic fiber manufacturing industry.

    PubMed

    Zheng, Tianlong; Wang, Qunhui; Zhang, Tao; Shi, Zhining; Tian, Yanli; Shi, Shanshan; Smale, Nicholas; Wang, Juan

    2015-04-28

    This work investigated microbubble-ozonation for the treatment of a refractory wet-spun acrylic fiber wastewater in comparison to macrobubble-ozonation. CODcr, NH3-N, and UV254 of the wastewater were removed by 42%, 21%, and 42%, respectively in the microbubble-ozonation, being 25%, 9%, and 35% higher than the removal rates achieved by macrobubble-ozonation at the same ozone dose. The microbubbles (with average diameter of 45μm) had a high concentration of 3.9×10(5) counts/mL at a gas flow rate of 0.5L/min. The gas holdup, total ozone mass-transfer coefficient, and average ozone utilization efficiency in the microbubble-ozonation were 6.6, 2.2, and 1.5 times higher than those of the macrobubble-ozonation. Greater generation of hydroxyl radicals and a higher zeta potential of the bubbles were also observed in the microbubble ozonation process. The biodegradability of the wastewater was also significantly improved by microbubble-ozonation, which was ascribed to the enhanced degradation of alkanes, aromatic compounds, and the many other bio-refractory organic compounds in the wastewater. Microbubble-ozonation can thus be a more effective treatment process than traditional macrobubble-ozonation for refractory wastewater produced by the acrylic fiber manufacturing industry. PMID:25681716

  2. Chitosan-poly(acrylic) acid polyionic complex: in vivo study to demonstrate prolonged gastric retention.

    PubMed

    Torrado, Susana; Prada, Pablo; de la Torre, Paloma M; Torrado, Santiago

    2004-02-01

    The aim of this study was to develop a chitosan-poly(acrylic) acid based controlled drug release system for gastric antibiotic delivery. Different mixtures of amoxicillin (A), chitosan (CS), and poly(acrylic) acid (PAA) were employed to obtain these polyionic complexes. A non-invasive method was employed for determining the gastric residence time of the formulations. It was studied the swelling behavior and drug release from these complexes. Gastric emptying rate study was performed by means of the [13C]octanoic acid breath test. The gastric emptying rates of two different formulations (conventional and gastric retentive system) were studied. Swelling studies indicated that the extent of swelling was greater in the polyionic complexes than in the single chitosan formulations. The amoxicillin diffusion from the hydrogels was controlled by the polymer/drug interaction. The property of these complexes to control the solute diffusion depends on the network mesh size, which is a significant factor in the overall behavior of the hydrogels. The gastric half-emptying time of the polyionic complex was significantly delayed compared to the reference formulation, showing mean values of 164.32+/-26.72 and 65.06+/-11.50min, respectively (P<0.01). The results of this study suggest that, these polyionic complexes are good systems for specific gastric drug delivery. PMID:14609680

  3. Olfactory function in chemical workers exposed to acrylate and methacrylate vapors.

    PubMed Central

    Schwartz, B S; Doty, R L; Monroe, C; Frye, R; Barker, S

    1989-01-01

    An investigation of the olfactory function of 731 workers at a chemical facility which manufacturers acrylates and methacrylates was undertaken using a standardized quantitative test. In a cross-sectional analysis of the data, no associations of chemical exposure with olfactory test scores were observed. A nested case-control study designed to evaluate the cumulative effects of exposure on olfactory function, however, revealed elevated crude exposure odds ratios (95% confidence interval) of 2.0 (1.1, 3.8) for all workers and 6.0 (1.7, 21.5) for workers who never smoked cigarettes. Logistic regression analysis, adjusting for multiple confounders, revealed exposure odds ratios of 2.8 (1.1, 7.0) and 13.5 (2.1, 87.6) in these same groups, respectively, and a dose-response relationship between olfactory dysfunction and cumulative exposure scores--semi-quantitative indices of lifetime exposure to the acrylates. The data also revealed decreasing exposure odds ratios with increasing duration since last exposure to these chemicals, suggesting that the effects may be reversible. PMID:2784947

  4. Influencing solvent miscibility and aqueous stability of aluminum nanoparticles through surface functionalization with acrylic monomers.

    PubMed

    Crouse, Christopher A; Pierce, Christian J; Spowart, Jonathan E

    2010-09-01

    With growing interest in the development of new composite systems for a variety of applications that require easily processable materials and adequate structural properties with high energy densities, we have pursued the chemical functionalization of oxide-passivated aluminum nanoparticles (nAl) using three acrylic monomers, 3-methacryloxypropyltrimethoxysilane (MPS), 2-carboxyethyl acrylate (CEA), and phosphonic acid 2-hydroxyethyl methacrylate ester (PAM), to provide chemical compatibility within various solvent and polymeric systems. Fourier transform infrared and X-ray photoelectron spectroscopy suggest that attachment of MPS and PAM monomers occurs through the formation of bonds directly to the passivated oxide surface upon reaction with surface hydroxyls, whereas CEA monomers interact through the formation of ionic carboxylate binding to aluminum atoms within the oxide. The coated particles demonstrate enhanced miscibility in common organic solvents and monomers; MPS and PAM coatings are additionally shown to inhibit oxidation of the aluminum particles when exposed to aqueous environments at room temperature, and PAM coatings are stable at even elevated temperatures. PMID:20795650

  5. A green approach to prepare silver nanoparticles loaded gum acacia/poly(acrylate) hydrogels.

    PubMed

    Bajpai, S K; Kumari, Mamta

    2015-09-01

    In this work, gum acacia (GA)/poly(sodium acrylate) semi-interpenetrating polymer networks (Semi-IPN) have been fabricated via free radical initiated aqueous polymerization of monomer sodium acrylate (SA) in the presence of dissolved Gum acacia (GA), using N,N'-methylenebisacrylamide (MB) as cross-linker and potassium persulphate (KPS) as initiator. The semi-IPNs, synthesized, were characterized by various techniques such as X-ray diffraction (XRD), thermo gravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The dynamic water uptake behavior of semi-IPNs was investigated and the data were interpreted by various kinetic models. The equilibrium swelling data were used to evaluate various network parameters. The semi-IPNs were used as template for the in situ preparation of silver nanoparticles using extract of Syzygium aromaticum (clove). The formation of silver nanoparticles was confirmed by surface plasmon resonance (SPR), XRD and transmission electron microscopy (TEM). Finally, the antibacterial activity of GA/poly(SA)/silver nanocomposites was tested against E. coli. PMID:26123815

  6. Synthesis and characterization of core-shell acrylate based latex and study of its reactive blends.

    PubMed

    Liu, Xiang; Fan, Xiao-Dong; Tang, Min-Feng; Nie, Ying

    2008-03-01

    Techniques in resin blending are simple and efficient method for improving the properties of polymers, and have been used widely in polymer modification field. However, polymer latex blends such as the combination of latexes, especially the latexes with water-soluble polymers, were rarely reported. Here, we report a core-shell composite latex synthesized using methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (EHA) and glycidyl methacrylate (GMA) as monomers and ammonium persulfate and sodium bisulfite redox system as the initiator. Two stages seeded semi-continuous emulsion polymerization were employed for constructing a core-shell structure with P(MMA-co-BA) component as the core and P(EHA-co-GMA) component as the shell. Results of Transmission Electron Microscopy (TEM) and Dynamics Light Scattering (DLS) tests confirmed that the particles obtained are indeed possessing a desired core-shell structural character. Stable reactive latex blends were prepared by adding the latex with waterborne melamine-formaldehyde resin (MF) or urea-formaldehyde resin (UF). It was found that the glass transition temperature, the mechanical strength and the hygroscopic property of films cast from the latex blends present marked enhancements under higher thermal treatment temperature. It was revealed that the physical properties of chemically reactive latexes with core-shell structure could be altered via the change of crosslinking density both from the addition of crosslinkers and the thermal treatment. PMID:19325753

  7. 4D printing smart biomedical scaffolds with novel soybean oil epoxidized acrylate

    PubMed Central

    Miao, Shida; Zhu, Wei; Castro, Nathan J.; Nowicki, Margaret; Zhou, Xuan; Cui, Haitao; Fisher, John P.; Zhang, Lijie Grace

    2016-01-01

    Photocurable, biocompatible liquid resins are highly desired for 3D stereolithography based bioprinting. Here we solidified a novel renewable soybean oil epoxidized acrylate, using a 3D laser printing technique, into smart and highly biocompatible scaffolds capable of supporting growth of multipotent human bone marrow mesenchymal stem cells (hMSCs). Porous scaffolds were readily fabricated by simply adjusting the printer infill density; superficial structures of the polymerized soybean oil epoxidized acrylate were significantly affected by laser frequency and printing speed. Shape memory tests confirmed that the scaffold fixed a temporary shape at −18 °C and fully recovered its original shape at human body temperature (37 °C), which indicated the great potential for 4D printing applications. Cytotoxicity analysis proved that the printed scaffolds had significant higher hMSC adhesion and proliferation than traditional polyethylene glycol diacrylate (PEGDA), and had no statistical difference from poly lactic acid (PLA) and polycaprolactone (PCL). This research is believed to significantly advance the development of biomedical scaffolds with renewable plant oils and advanced 3D fabrication techniques. PMID:27251982

  8. Synthesis and Characterization of Core-Shell Acrylate Based Latex and Study of Its Reactive Blends

    PubMed Central

    Liu, Xiang; Fan, Xiao-Dong; Tang, Min-Feng; Nie, Ying

    2008-01-01

    Techniques in resin blending are simple and efficient method for improving the properties of polymers, and have been used widely in polymer modification field. However, polymer latex blends such as the combination of latexes, especially the latexes with water-soluble polymers, were rarely reported. Here, we report a core-shell composite latex synthesized using methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (EHA) and glycidyl methacrylate (GMA) as monomers and ammonium persulfate and sodium bisulfite redox system as the initiator. Two stages seeded semi-continuous emulsion polymerization were employed for constructing a core-shell structure with P(MMA-co-BA) component as the core and P(EHA-co-GMA) component as the shell. Results of Transmission Electron Microscopy (TEM) and Dynamics Light Scattering (DLS) tests confirmed that the particles obtained are indeed possessing a desired core-shell structural character. Stable reactive latex blends were prepared by adding the latex with waterborne melamine-formaldehyde resin (MF) or urea-formaldehyde resin (UF). It was found that the glass transition temperature, the mechanical strength and the hygroscopic property of films cast from the latex blends present marked enhancements under higher thermal treatment temperature. It was revealed that the physical properties of chemically reactive latexes with core-shell structure could be altered via the change of crosslinking density both from the addition of crosslinkers and the thermal treatment. PMID:19325753

  9. Characterization of thin-film deposition in a pulsed acrylic acid polymerizing discharge

    SciTech Connect

    Voronin, Sergey A.; Bradley, James W.; Fotea, Catalin; Zelzer, Mischa; Alexander, Morgan R.

    2007-07-15

    In this study, thin-film deposition in a pulsed rf polymerizing discharge (13.56 MHz) struck in acrylic acid has been investigated by mass spectrometry, x-ray photoelectron spectroscopy, and quartz crystal microbalance techniques. The experiment was conducted at a fixed acrylic acid pressure of 1.3 Pa and 'on' pulse duration of 0.1 ms, whereas the 'off' time was varied between 0 and 20 ms. The rf input power in the 'on' time and gas flow rate were varied between 10 and 50 W and 1.5 and 4.8 sccm (sccm denotes cubic centimeter per minute at STP), respectively. These changes of the discharge conditions resulted in large-scale progressive variations in film and gas-phase plasma composition. In particular, the -COOH functionality of the monomer was increasingly retained in the plasma-generated thin films as the duty cycle was lowered (i.e., with lowered time-averaged powers). The monomer retention reached its maximum value of 66% for 'off' times exceeding 5 ms, when the discharge was operating in the power-deficient regime. The results show that the film deposition rate is a strong function of the monomer flow rate, whereas -COOH retention is correlated to the amount of unfragmented monomer in the plasma, controlled by the applied power.

  10. Precipitation-Redispersion of Cerium Oxide Nanoparticles with Poly(acrylic acid): Toward Stable Dispersions

    SciTech Connect

    Sehgal,A.; Lalatonne, Y.; Berret, J.; Morvan, M.

    2005-01-01

    We exploit a precipitation-redispersion mechanism for complexation of short chain polyelectrolytes with cerium oxide nanoparticles to extend their stability ranges. As synthesized, cerium oxide sols at pH 1.4 consist of monodisperse cationic nanocrystalline particles having a hydrodynamic diameter of 10 nm and a molecular weight of 400 000 g mol{sup -1}. We show that short chain uncharged poly(acrylic acid) at low pH when added to a cerium oxide sols leads to macroscopic precipitation. As the pH is increased, the solution spontaneously redisperses into a clear solution of single particles with an anionic poly(acrylic acid) corona. The structure and dynamics of cerium oxide nanosols and their hybrid polymer-inorganic complexes in solution are investigated by static and dynamic light scattering, X-ray scattering, and chemical analysis. Quantitative analysis of the redispersed sol gives rise to an estimate of 40-50 polymer chains per particle for stable suspension. This amount represents 20% of the mass of the polymer-nanoparticle complexes. This complexation adds utility to the otherwise unstable cerium oxide dispersions by extending the range of stability of the sols in terms of pH, ionic strength, and concentration.

  11. Exposure assessment of acrylates/methacrylates in radiation-cured applications

    SciTech Connect

    Not Available

    1987-09-25

    Occupational exposures to radiation-cured acrylates/methacrylates during their processing and use in coatings, inks, and adhesives were evaluated in 12 walk-through surveys at formulator and applicator sites. Inhalation and dermal-exposure routes were studied. According to the authors, the basic process used to formulate coatings, inks, and adhesives consists of blending raw materials in closed mixing vessels using local exhaust ventilation in the form of elephant trunks at vessel charging and packaging locations. Application methods surveyed included reverse-roll coaters, direct roll coaters, curtain/rain coaters, laminators, pneumatic injection, spray guns, and manual application. At the sites surveyed, the number of workers potentially exposed at each site ranged from two to 142. Process operators at applicator sites had the greatest potential for dermal exposure. Generally, the potential for inhalation exposure was low due to low volatility of the multifunctional acrylates/methacrylates used in the formulations. No reliable air-monitoring data were available at any site. Respirator use was limited and sporadic.

  12. Aggregation of poly(acrylic acid)-containing elastin-mimetic copolymers

    PubMed Central

    Paik, Bradford A.; Blanco, Marco A.; Jia, Xinqiao; Roberts, Christopher J.; Kiick, Kristi L.

    2015-01-01

    Polymer-peptide conjugates were produced via the copper-catalyzed alkyne-azide cycloaddition of poly(tert butyl acrylate) (PtBA) and elastin-like peptides. An azide-functionalized polymer was produced via atom-transfer radical polymerization (ATRP) followed by conversion of bromine end groups to azide groups. Subsequent reaction of the polymer with a bis-alkyne-functionalized, elastin-like peptide proceeded with high efficiency, yielding di- and tri-block conjugates, which after deprotection, yielded poly(acrylic acid) (PAA)-based diblock and triblock copolymers. These conjugates were solubilized in dimethyl formamide, and titration of phosphate buffered saline (PBS) induced aggregation. The presence of polydisperse spherical aggregates was confirmed by dynamic light scattering and transmission electron microscopy. Additionally, a coarse-grained molecular model was designed to reasonably capture inter- and intramolecular interactions for the conjugates and its precursors. This model was used to assess the effect of the different interacting molecular forces on the conformational thermodynamic stability of the copolymers. Our results indicated that the PAA’s ability to hydrogen-bond with both itself and the peptide is the main interaction for stabilizing the diblocks and triblocks and driving their self-assembly, while interactions between peptides are suggested to play only a minor role on the conformational and thermodynamic stability of the conjugates. PMID:25611563

  13. High Methane Storage Working Capacity in Metal-Organic Frameworks with Acrylate Links.

    PubMed

    Jiang, Juncong; Furukawa, Hiroyasu; Zhang, Yue-Biao; Yaghi, Omar M

    2016-08-17

    High methane storage capacity in porous materials is important for the design and manufacture of vehicles powered by natural gas. Here, we report the synthesis, crystal structures and methane adsorption properties of five new zinc metal-organic frameworks (MOFs), MOF-905, MOF-905-Me2, MOF-905-Naph, MOF-905-NO2, and MOF-950. All these MOFs consist of the Zn4O(-CO2)6 secondary building units (SBUs) and benzene-1,3,5-tri-β-acrylate, BTAC. The permanent porosity of all five materials was confirmed, and their methane adsorption measured up to 80 bar to reveal that MOF-905 is among the best performing methane storage materials with a volumetric working capacity (desorption at 5 bar) of 203 cm(3) cm(-3) at 80 bar and 298 K, a value rivaling that of HKUST-1 (200 cm(3) cm(-3)), the benchmark compound for methane storage in MOFs. This study expands the scope of MOF materials with ultrahigh working capacity to include linkers having the common acrylate connectivity. PMID:27442620

  14. Chromatic stability of acrylic resins of artificial eyes submitted to accelerated aging and polishing

    PubMed Central

    GOIATO, Marcelo Coelho; dos SANTOS, Daniela Micheline; SOUZA, Josiene Firmino; MORENO, Amália; PESQUEIRA, Aldiéris Alves

    2010-01-01

    Esthetics and durability of materials used to fabricate artificial eyes has been an important eissue since artificial eyes are essential to restore esthetics and function, protect the remaining tissues and help with patients' psychological therapy. However, these materials are submitted to degrading effects of environmental agents on the physical properties of the acrylic resin. Objective This study assessed the color stability of acrylic resins used to fabricate sclera in three basic shades (N1, N2 and N3) when subjected to accelerated aging, mechanical and chemical polishing. Material and methods Specimens of each resin were fabricated and submitted to mechanical and chemical polishing. Chromatic analysis was performed before and after accelerated aging through ultraviolet reflection spectrophotometry. Results All specimens revealed color alteration following polishing and accelerated aging. The resins presented statistically significant chromatic alteration (p<0.01) between the periods of 252 and 1008 h. Conclusions Both polishing methods presented no significant difference between the values of color derivatives of resins. PMID:21308298

  15. Mechanical, material, and antimicrobial properties of acrylic bone cement impregnated with silver nanoparticles.

    PubMed

    Slane, Josh; Vivanco, Juan; Rose, Warren; Ploeg, Heidi-Lynn; Squire, Matthew

    2015-03-01

    Prosthetic joint infection is one of the most serious complications that can lead to failure of a total joint replacement. Recently, the rise of multidrug resistant bacteria has substantially reduced the efficacy of antibiotics that are typically incorporated into acrylic bone cement. Silver nanoparticles (AgNPs) are an attractive alternative to traditional antibiotics resulting from their broad-spectrum antimicrobial activity and low bacterial resistance. The purpose of this study, therefore, was to incorporate metallic silver nanoparticles into acrylic bone cement and quantify the effects on the cement's mechanical, material and antimicrobial properties. AgNPs at three loading ratios (0.25, 0.5, and 1.0% wt/wt) were incorporated into a commercial bone cement using a probe sonication technique. The resulting cements demonstrated mechanical and material properties that were not substantially different from the standard cement. Testing against Staphylococcus aureus and Staphylococcus epidermidis using Kirby-Bauer and time-kill assays demonstrated no antimicrobial activity against planktonic bacteria. In contrast, cements modified with AgNPs significantly reduced biofilm formation on the surface of the cement. These results indicate that AgNP-loaded cement is of high potential for use in primary arthroplasty where prevention of bacterial surface colonization is vital. PMID:25579913

  16. The Reinforcement Effect of Nano-Zirconia on the Transverse Strength of Repaired Acrylic Denture Base

    PubMed Central

    ArRejaie, Aws S.; Abdel-Halim, Mohamed Saber; Rahoma, Ahmed

    2016-01-01

    Objective. The aim of this study was to evaluate the effect of incorporation of glass fiber, zirconia, and nano-zirconia on the transverse strength of repaired denture base. Materials and Methods. Eighty specimens of heat polymerized acrylic resin were prepared and randomly divided into eight groups (n = 10): one intact group (control) and seven repaired groups. One group was repaired with autopolymerized resin while the other six groups were repaired using autopolymerized resin reinforced with 2 wt% or 5 wt% glass fiber, zirconia, or nano-zirconia particles. A three-point bending test was used to measure the transverse strength. The results were analyzed using SPSS and repeated measure ANOVA and post hoc least significance (LSD) test (P ≤ 0.05). Results. Among repaired groups it was found that autopolymerized resin reinforced with 2 or 5 wt% nano-zirconia showed the highest transverse strength (P ≤ 0.05). Repairs with autopolymerized acrylic resin reinforced with 5 wt% zirconia showed the lowest transverse strength value. There was no significant difference between the groups repaired with repair resin without reinforcement, 2 wt% zirconia, and glass fiber reinforced resin. Conclusion. Reinforcing of repair material with nano-zirconia may significantly improve the transverse strength of some fractured denture base polymers. PMID:27366150

  17. Spectroscopic and density functional theory studies of trans-3-(trans-4-imidazolyl)acrylic acid.

    PubMed

    Arjunan, V; Remya, P; Sathish, U; Rani, T; Mohan, S

    2014-08-14

    The structural parameters, thermodynamic properties and vibrational frequencies of the optimised geometry of trans-3-(trans-4-imidazolyl)acrylic acid have been determined from B3LYP methods with 6-311++G(**) and cc-pVTZ basis sets. The effects of substituents (acrylyl group) on the imidazole vibrational frequencies are analysed. The vibrational frequencies of the fundamental modes of trans-3-(trans-4-imidazolyl)acrylic acid have been precisely assigned and analysed and the theoretical results are compared with the experimental vibrations. (1)H and (13)C NMR isotropic chemical shifts are calculated and the assignments made are compared with the experimental values. The energies of important MO's of the compound are also determined from DFT method. The total electron density and electrostatic potential of the compound are determined by natural bond orbital analysis. Various reactivity and selectivity descriptors such as chemical hardness, chemical potential, softness, electrophilicity, nucleophilicity and the appropriate local quantities employing natural population analysis (NPA) are calculated. PMID:24755636

  18. Synthesis and effect of modification on methacylate - acrylate microspheres for Trametes versicolor laccase enzyme immobilization

    NASA Astrophysics Data System (ADS)

    Mazlan, Siti Zulaikha; Hanifah, Sharina Abu

    2014-09-01

    Immobilization of laccase on the modified copolymer methacrylate-acrylate microspheres was studied. A poly (glycidyl methacrylate-co-n-butyl acrylate) microsphere consists of epoxy groups were synthesized using suspension photocuring technique. The epoxy group in poly (GMA-nBA) microspheres were converted into amino groups with aldehyde group. Laccase immobilization is based on having the amino groups on the enzyme surface and aldehyde group on the microspheres via covalent binding. Fourier transform infrared spectroscopy (FT-IR) analysis proved the successful surface modification on microspheres. The FTIR spectrum shows the characteristic peaks at 1646 cm-1 assigned to the conformation of the polymerization that took place between monomer GMA and nBA respectively. In addition, after modification, FTIR peaks that assigned to the epoxy ring (844 cm-1 and 904 cm-1) were decreased. The results obtained from FTIR method signify good agreement with the epoxy content method. Hence, the activity of the laccase-immobilized microspheres increased upon increasing the epoxy content. Furthermore, poly (GMA-nBA) exhibited uniform microspheres with below 2 μm surface. Immobilized enzyme showed a broader pH profile and higher temperature compared native enzyme.

  19. Spectroscopic and density functional theory studies of trans-3-(trans-4-imidazolyl)acrylic acid

    NASA Astrophysics Data System (ADS)

    Arjunan, V.; Remya, P.; Sathish, U.; Rani, T.; Mohan, S.

    2014-08-01

    The structural parameters, thermodynamic properties and vibrational frequencies of the optimised geometry of trans-3-(trans-4-imidazolyl)acrylic acid have been determined from B3LYP methods with 6-311++G** and cc-pVTZ basis sets. The effects of substituents (acrylyl group) on the imidazole vibrational frequencies are analysed. The vibrational frequencies of the fundamental modes of trans-3-(trans-4-imidazolyl)acrylic acid have been precisely assigned and analysed and the theoretical results are compared with the experimental vibrations. 1H and 13C NMR isotropic chemical shifts are calculated and the assignments made are compared with the experimental values. The energies of important MO’s of the compound are also determined from DFT method. The total electron density and electrostatic potential of the compound are determined by natural bond orbital analysis. Various reactivity and selectivity descriptors such as chemical hardness, chemical potential, softness, electrophilicity, nucleophilicity and the appropriate local quantities employing natural population analysis (NPA) are calculated.

  20. Precision synthesis of bio-based acrylic thermoplastic elastomer by RAFT polymerization of itaconic acid derivatives.

    PubMed

    Satoh, Kotaro; Lee, Dong-Hyung; Nagai, Kanji; Kamigaito, Masami

    2014-01-01

    Bio-based polymer materials from renewable resources have recently become a growing research focus. Herein, a novel thermoplastic elastomer is developed via controlled/living radical polymerization of plant-derived itaconic acid derivatives, which are some of the most abundant renewable acrylic monomers obtained via the fermentation of starch. The reversible addition-fragmentation chain-transfer (RAFT) polymerizations of itaconic acid imides, such as N-phenylitaconimide and N-(p-tolyl)itaconimide, and itaconic acid esters, such as di-n-butyl itaconate and bis(2-ethylhexyl) itaconate, are examined using a series of RAFT agents to afford well-defined polymers. The number-average molecular weights of these polymers increase with the monomer conversion while retaining relatively narrow molecular weight distributions. Based on the successful controlled/living polymerization, sequential block copolymerization is subsequently investigated using mono- and di-functional RAFT agents to produce block copolymers with soft poly(itaconate) and hard poly(itaconimide) segments. The properties of the obtained triblock copolymer are evaluated as bio-based acrylic thermoplastic elastomers. PMID:24243816