Sample records for dowex 50w resins

  1. Distribution ratios on Dowex 50W resins of metal leached in the caron nickel recovery process

    SciTech Connect

    Reynolds, B.A.; Metsa, J.C.; Mullins, M.E.

    1980-05-01

    Pressurized ion exchange on Dowex 50W-X8 and 50W-X12 resins was investigated using elution techniques to determine distribution ratios for copper, nickel, and cobalt complexes contained in ammonium carbonate solution, a mixture which approximates the waste liquor from the Caron nickel recovery process. Results were determined for different feed concentrations, as well as for different concentrations and pH values of the ammonium carbonate eluant. Distribution ratios were compared with those previously obtained from a continuous annular chromatographic system. Separation of copper and nickel was not conclusively observed at any of the conditions examined.

  2. Preconcentration of trace multi-elements in water samples using Dowex 50W-x8 and Chelex-100 resins prior to their determination using inductively coupled plasma atomic emission spectrometry (ICP-OES)

    NASA Astrophysics Data System (ADS)

    Nomngongo, Philiswa N.; Catherine Ngila, J.; Msagati, Titus A. M.; Moodley, Brenda

    This work presents a solid phase extraction (SPE) method for simultaneous preconcentration of trace elements in water samples prior to their ICP-OES determination. Dowex 50W-x8 and Chelex-100 resins were used as SPE sorbent materials for preconcentration of trace Cd, Co, Cr, Cu, Fe, Ni, Pb and Zn. The optimum sample pH, eluent concentration and sample flow rates were found to 6, 3.0 mol L-1 and 3.0 mL min-1, respectively. In terms of multi-element preconcentration capabilities, Dowex 50W-x8 appeared to be a better sorbent. The recoveries for all the tested analytes were >95%. However, Chelex-100 showed a better performance in terms of recovery (>95%) towards Cu, Fe and Zn. Under optimized conditions using Dowex 50W-x8, the relative standard deviations for different metals were <3%. The limits of detection and limits of quantification ranged from 0.01-0.39 ?g L-1 and 0.05-0.1.3 ?g L-1, respectively. The accuracy of the preconcentration method was confirmed by spike recovery test and the analysis of certified reference materials. The SPE method was applied for preconcentration of the analyte ions in tap water, bottled water and wastewater samples.

  3. Screening of Dowex anion-exchange resins for invertase immobilization.

    PubMed

    Tomotani, Ester Junko; Vitolo, Michele

    2004-01-01

    Commercial yeast invertase (Bioinvert) was immobilized by adsorption on anion-exchange resins, collectively named Dowex(R) (1x8:50-400, 1x4:50-400, and 1x2:100-400). Optimal binding was obtained at pH 5.5 and 32 degrees C. Among different polystyrene beads, the complex Dowex-1x4-200/invertase showed a yield coupling and an immobilization coefficient equal to 100%. The thermodynamic and kinetic parameters for sucrose hydrolysis for both soluble and insoluble enzyme were evaluated. The complex Dowex/invertase was stable without any desorption of enzyme from the support during the reaction, and it had thermodynamic parameters equal to the soluble form. The stability against pH presented by the soluble invertase was between 4.0 and 5.0, whereas for insoluble enzyme it was between 5.0 and 6.0. In both cases, the optimal pH values were found in the range of the stability interval. The Km and Vmax for the immobilized invertase were 38.2 mM and 0.0489 U/mL, and for the soluble enzyme were 40.3 mM and 0.0320 U/mL. PMID:15054202

  4. Separation of metallic impurities from uranium by anion exchange on Dowex 1×8 resin

    Microsoft Academic Search

    R. J. Rosenberg; A.-M. Forsbacka; N. Gras

    1991-01-01

    The separation of metallic impurities from uranium by anion exchange with a Dowex 1×8 resin has been investigated. The following elements can be quantitatively separated from 400 mg uranium using a 1 cm diameter 15 or 30 cm long column. The elements Ag, Al, Ba, Ca, Cr, Cs, K, Mg, Mn, Na, Ni, Rb, REE, Sc, Th, Ti and Y

  5. Radiation effects on Dowex MSC1, Amberlite 252, and Duolite C-264 ion exchange resins. [Gamma rays

    Microsoft Academic Search

    A. R. Kazanjian; J. R. Stevens

    1983-01-01

    The radiation effects on three new cation exchange resins were investigated. The resins were Dowex MSC-1, Amberlite 252, and Duolite C-264. The properties examined were ion exchange capacity, moisture content, plutonium loading and elution characteristics, thermal stability, and gas generation. There were some differences in the radiation effects on these properties but the overall radiation stability was considered to be

  6. Use of Cation Exchange Resins for Production of U{sub 3}O{sub 8} Suitable for the Al-U{sub 3}O{sub 8} Powder Metallurgy Process

    SciTech Connect

    Mosley, W.C.

    2001-09-17

    This report describes the production of U{sub 3}O{sub 8} powders from three types of cation exchange resins: Dowex 50W, a strong acid, sulfonate resin; AG MP-50, a macroporous form of sulfonate resin; and Bio-Rex 70, a weak acid, carboxylic resin.

  7. Chemiluminescent flow sensor for H 2O 2 based on the decomposition of H 2O 2 catalyzed by cobalt(II)-ethanolamine complex immobilized on resin

    Microsoft Academic Search

    Soichi Hanaoka; Jin-Ming Lin; Masaaki Yamada

    2001-01-01

    The decomposition of H2O2 catalyzed by transition metal ion has been investigated by chemiluminescence (CL). Using a heterogeneous catalyst, Co(II)-monoethanolamine complex immobilized on Dowex-50W resin, the rapid decomposition of H2O2 was observed. A very weak CL appeared during the H2O2 solution mixed with the immobilized resin by batch method. When appropriate amount of neutral luminol solution was added into the

  8. ION EXCHANGE STUDIES IN CONCENTRATED SOLUTIONS. I. THE ALKALI CATIONS WITH A SULFONIC ACID RESIN

    Microsoft Academic Search

    D. C. Whitney; R. M. Diamond

    1962-01-01

    An investigation of the cation exchange behavior on Dowex-50W (sulfonic-; acid type) resin of Na, Rb, and Cs traccrs in 0.1 M to saturated solutions of ; HClOâ, HCl, HNOâ, HCâHgOâ, the corresponding Li salts, ; and CsCl was made. The exchange in dilute solutions is discussed in terms of the ; competition for solvation of the cation between water

  9. THE EFFECT OF PLATING ADDITIVES ON THE RECOVERY OF COPPER FROM DILUTE AQUEOUS SOLUTIONS USING THE CHELATING RESIN DOWEX M4195

    Microsoft Academic Search

    William Ewing; James W. Evans; Fiona M. Doyle

    Copper is rapidly being adopted by the semiconductor industry as the interconnect material of choice. The aqueous processing techniques used generate wastes such as spent electrolyte from electroplating, electroplating rinse water, copper solutions from removing copper from the back of the wafer and CMP waste streams. We are examining the use of chelating resins as a means of recovering copper

  10. Pre-concentration of trace elements in short chain alcohols using different commercial cation exchange resins prior to inductively coupled plasma-optical emission spectrometric detection.

    PubMed

    Nomngongo, Philiswa N; Catherine Ngila, J; Kamau, Joseph N; Msagati, Titus A M; Marjanovic, Ljiljana; Moodley, Brenda

    2013-07-17

    Chelex-100, Dowex 50W-x8 and Dowex MAC-3 exchange resins were investigated for separation and pre-concentration of trace amounts of Cd, Cr, Cu, Fe, Mn, Pb, Ti and Zn in alcohols with respect to retention and desorption characteristics. Dowex 50W-x8 was found to be the best sorbent with percentages recoveries >95%. In addition, Chelex-100 appeared to be suitable for the pre-concentration of Cu, Fe and Zn, whereas Dowex MAC-3 was selective for Cu and Fe. Therefore, Dowex 50W-x8 was used for further investigations. The relative standard deviations <4% (n=20), limits of detection and quantification were 0.1-1.2 ?g L(-1) and 0.3-1.5 ?g L(-1), respectively. The SPE method was validated against a certified reference material and the results were in agreement with certified values. The accuracy of the optimized method was verified by the recovery test in the spiked alcohol samples. The accuracy and spike recovery test for different metal ions were in the range 98-102% and 95-105%, respectively. The optimized method was applied to the separation and pre-concentration of metal ions in different commercial alcohol samples. PMID:23830424

  11. Kinetics of esterification of propionic acid with n-amyl alcohol in the presence of cation exchange resins

    Microsoft Academic Search

    Beyhan Erdem; Mustafa Cebe

    2006-01-01

    Esterifications of n-amyl alcohol with propionic acid catalyzed by macroporous (Amberlyst-15) and microporous (Dowex 50 W\\u000a and Amberlite IR-120) polymeric ion-exchange resins were carried out between 333–348 K. When these catalysts were used as\\u000a commercially available, Amberlyst-15 was observed to be the most effective catalyst with respect to rate constants, but after\\u000a drying it became the less effective one. The

  12. DISTRIBUTION COEFFICIENTS AND ION EXCHANGE BEHAVIOUR OF SOME CHLORIDE COMPLEX FORMING ELEMENTS WITH BIO RAD AG50W-XB CATION EXCHANGE RESIN IN MIXED NITRIC-HYDROCHLORIC ACID SOLUTIONS

    Microsoft Academic Search

    F. W. E. Strelow

    1989-01-01

    Cation exchange equilibrium distribution coefficients are presented for the chloride complex forming elements Au(III), Tl(III), Hg(II), Bi(III), In, Cd, Zn, Pb(II), Fe(III) and Ga with a microporous (gel-type) resin of 8% DVB crosslinkage in hydrochloric-nitric acid mixtures ranging from 0.02M to 0.50M and from 0.20M to 2.0M concentrations, respectively. Separations which are possible by using mixtures and pure hydrochloric acid

  13. THE EXTRACTION OF SILVER FROM CYANIDE SOLUTIONS WITH ION EXCHANGE RESINS

    Microsoft Academic Search

    P. A. Riveros; W. Charles Cooper

    1985-01-01

    The ability of various ion exchange resins to extract silver from synthetic cyanide solutions was evaluated. It was found that weak base resins such as DUOLITE A-7, DOWEX WGR-2, DOWEX MWA-1, DOWEX XFS-4195, and AMBERLITE IRA-35 extract silver significantly only when the pH is lower than 8. At higher pH, the same resins exhibited little or no silver extraction. A

  14. Uranium Adsorption on Ion-Exchange Resins - Batch Testing

    SciTech Connect

    Mattigod, Shas V.; Golovich, Elizabeth C.; Wellman, Dawn M.; Cordova, Elsa A.; Smith, Ronald M.

    2010-12-01

    The uranium adsorption performance of five resins (Dowex 1, Dowex 21K 16-30 [fresh], Dowex 21K 16-30 [regenerated], Purofine PFA600/4740, and ResinTech SIR-1200) were tested using unspiked, nitrate-spiked, and nitrate-spiked/pH adjusted source water from well 299-W19-36. These batch tests were conducted in support of a resin selection process in which the best resin to use for uranium treatment in the 200-West Area groundwater pump-and-treat system will be identified. The results from these tests are as follows: • The data from the high-nitrate (1331 mg/L) tests indicated that Dowex 1, Dowex 21K 16-30 (fresh), Purofine PFA600/4740, and ResinTech SIR-1200 all adsorbed uranium similarly well with Kd values ranging from ~15,000 to 95,000 ml/g. All four resins would be considered suitable for use in the treatment system based on uranium adsorption characteristics. • Lowering the pH of the high nitrate test conditions from 8.2 to 7.5 did not significantly change the uranium adsorption isotherms for the four tested resins. The Kd values for these four resins under high nitrate (1338 mg/L), lower pH (7.5) ranged from ~15,000 to 80,000 ml/g. • Higher nitrate concentrations greatly reduced the uranium adsorption on all four resins. Tests conducted with unspiked (no amendments; nitrate at 337 mg/L and pH at 8.2) source water yielded Kd values for Dowex 1, Dowex 21K 16-30 (fresh), Purofine PFA600/4740, and ResinTech SIR-1200 resins ranging from ~800,000 to >3,000,000 ml/g. These values are about two orders of magnitude higher than the Kd values noted from tests conducted using amended source water. • Compared to the fresh resin, the regenerated Dowex 21K 16-30 resin exhibited significantly lower uranium-adsorption performance under all test conditions. The calculated Kd values for the regenerated resin were typically an order of magnitude lower than the values calculated for the fresh resin. • Additional testing using laboratory columns is recommended to better resolve differences between the adsorption abilities of the resins and to develop estimates of uranium loading on the resins. By determining the quantity of uranium that each resin can adsorb and the time required to reach various levels of loading, resin lifetime in the treatment system can be estimated.

  15. Plutonium and neptunium recovery, separation, and purification with organic ion exchange resins

    Microsoft Academic Search

    J. D. Navratil; J. L. Ryan

    1979-01-01

    Amberlite, Duolite, Ionac A-581 and A-580, and Dowex resins were screened for use in plutonium and neptunium recovery and purification processes. The sorption and elution kinetics and column loading and elution characteristics were investigated.

  16. Sodium Guidestar Radiometry Results from the SOR's 50W Fasor

    Microsoft Academic Search

    Jack Drummond; J. Telle; Craig Denman; Paul Hillman; G. Moore; S. Novotny; R. Fugate; M. Eichoff

    2006-01-01

    Having upgraded the 20W, 589nm fasor (frequency-addition source of optical radiation) reported at the last AMOS conference to 50W, we have since produced a sodium laser guidestar (LGS) with a V1 magnitude of 5.1 for 30W of fasor power in November 2005, when the annual peak in mesospheric sodium density occurs. This corresponds to a return flux at the top

  17. Characterization of soil phosphorus by anion exchange resin adsorption and P 32 -equilibration

    Microsoft Academic Search

    F. Amer; D. R. Bouldin; C. A. Black; F. R. Duke

    1955-01-01

    Summary Adsorption of phosphate by the anion-exchange resin Dowex-2 was investigated. The resin adsorbed small quantities of P from solution quantitatively. The rate of P-adsorption by resin agitated in solution was proportional to the P-concentration in solution, and was independent of the rate of diffusion of adsorbed P in the resin. When 1 g of soil was shaken continuously with

  18. Boron Removal from Aqueous Solution by Ion-Exchange Resin: Column Sorption Elution Studies

    Microsoft Academic Search

    T. E. Bekta?; N. Öztiirk

    2004-01-01

    A column sorption-elution study was carried out by using a strong base anion exchange resin (Dowex 2x8) for the removal of boron from aqueous solution. The breakthrough curve was obtained as a function of feed flow rate and capacity value of resin was calculated. The boron on the resin was quantitatively eluted with 0.5M HCl solution at different flow rates.

  19. Boron removal from aqueous solutions by ion-exchange resin: Column sorption–elution studies

    Microsoft Academic Search

    T. Ennil Köse; Ne?e Öztürk

    2008-01-01

    A column sorption–elution study was carried out by using a strong base anion-exchange resin (Dowex 2×8) for the removal of boron from aqueous solutions. The breakthrough curve was obtained as a function of feed flow rate and the total and breakthrough capacity values of the resin were calculated. The boron on the resin was quantitatively eluted with 0.5M HCl solution

  20. Biochemical characterization of extracellular polymeric substances extracted from an intertidal mudflat using a cation exchange resin

    Microsoft Academic Search

    Guillaume Pierre; Marianne Graber; Francis Orvain; Christine Dupuy; Thierry Maugard

    2010-01-01

    The biochemical characterization of Extracellular Polymeric Substances (EPS) excreted in a European intertidal mudflat (Marennes–Oléron Bay) was performed. Experiments were carried out for the first time in situ, by using an improved extraction recently developed. This innovative procedure, using a cation exchange resin (Dowex), allows separating precisely different fractions of EPS, especially pure bound EPS. Moreover, it avoids the contamination

  1. Evaluation of Selective Ion Exchange Resins for Removal of Mercury from the H-Area Water Treatment Unit

    SciTech Connect

    Serkiz, S.M.

    2000-09-05

    This study investigated the ability of seven ion exchange (IX) resins, some of which were mercury specific, to remove mercury in H-Area WTU waters from three sources (Reverse Osmosis (RO) Feed, RO Permeate from Train A, and a mercury ''hot spot'' extraction well HEX 18). Seven ion exchange resins, including ResinTech CG8 and Dowex 21K (the cation and anion exchange resins currently used at the H-Area WTU) were screened against five alternative ion exchange materials plus an experimental blank. Mercury decontamination factors (DFs), mercury breakthrough, and post-test contaminant concentrations of IX resins were determined for each IX material tested.

  2. Design, integration and demonstration of a 50 W JP8\\/kerosene fueled portable SOFC power generator

    Microsoft Academic Search

    Praveen K. Cheekatamarla; Caine M. Finnerty; Charles R. Robinson; Stanley M. Andrews; Jonathan A. Brodie; Y. Lu; Paul G. DeWald

    2009-01-01

    A man-portable solid oxide fuel cell (SOFC) system integrated with desulfurized JP8 partial oxidation (POX) reformer was demonstrated to supply a continuous power output of 50W. This paper discusses some of the design paths chosen and challenges faced during the thermal integration of the stack and reformer in aiding the system startup and shutdown along with balance of plant and

  3. PREPARATION OF LITHIUM ISOTOPE STANDARDS. I. SEPARATION OF SODIUM AND LITHIUM BY DOWEX 50-X16 DVB RESIN

    Microsoft Academic Search

    W. C. Dietrich; R. E. Barringer

    1959-01-01

    In support of the lithium isotope standards program, a procedure is ; prescribed for the separation of sodium from lithium in a hydrochloric acid ; medium. This separation is effected by a Duwex 50-X16 DBV ion exchange column ; under conditions of high resolution chromatography. (auth);

  4. Selective recovery of Cr and Cu in leachate from chromated copper arsenate treated wood using chelating and acidic ion exchange resins

    Microsoft Academic Search

    Amélie Janin; Jean-François Blais; Guy Mercier; Patrick Drogui

    2009-01-01

    The purpose of this study was to selectively remove chromium and copper from CCA-treated wood acid leachates (initial concentrations of 447–651mg As l?1, 374–453mg Cu l?1 and 335–622mg Cr l?1) using ion exchange resins and precipitation techniques. Batch experiments revealed that the chelating resin Dowex M4195 had a high copper selectivity in the presence of chromium while the Amberlite IR120

  5. Micromachining with a 50 W, 50 ?J, subpicosecond fiber laser system

    NASA Astrophysics Data System (ADS)

    Shah, Lawrence; Fermann, Martin E.; Dawson, Jay W.; Barty, Christopher P. J.

    2006-12-01

    A 50 W sub-picosecond fiber chirped pulse amplification system generating 50 ?J pulses at a repetition rate of 1 MHz is demonstrated. As required for precision high speed micro-machining, this system has a practical system configuration enabled by the fiber stretcher and 1780 l/mm dielectric diffraction grating compressor and is capable of ablation rates >0.17 mm3/s metal, ceramic, and glass.

  6. Interannual variability of the shelf-slope front position between 75° and 50° W

    Microsoft Academic Search

    James J. Bisagni; Hyun-Sook Kim; Ayan Chaudhuri

    2009-01-01

    The shelf-slope front (SSF) is a continuous shelf-break front running from the Tail of the Grand Banks to Cape Hatteras, North Carolina, separating colder and less-saline continental shelf waters from warmer and more saline slope waters. Time series containing mean monthly SSF positions were produced along each of 26 longitude lines between 75° and 50°W by workers located at Bedford

  7. The effects of ionizing radiation on Reillex trademark HPQ, a new macroporous polyvinylpyridine resin, and on four conventional polystyrene anion exchange resins

    SciTech Connect

    Marsh, S.F.

    1990-11-01

    This study compares the effects of ionizing radiation on Reillex{trademark} HPQ, a recently available macroporous copolymer of 1-methyl-4-vinylpyridine/divinylbenzene, and on four conventional strong-base polystyrene anion exchange resins. The polystyrene resins investigated included one gel type, Dowex{trademark} 1 {times} 4, and three macroporous resins: Dow{trademark} MSA-1, Amberlite{trademark} IRA-900, and Lewatit{trademark} MP-500-FK. Each resin, in 7 M nitric acid, was subjected to seven different levels of {sup 60}Co gamma radiation ranging from 100 to 1000 megarads. Irradiated resins were measured for changes in dry weight, wet volume, chloride and Pu(IV) exchange capacities, and thermal stability. In separate experiments, each resin was subjected to approximately 340 megarads of in situ alpha particles from sorbed plutonium. Resin damage from alpha particles was less than half that caused by gamma rays, which may be a consequence of different production rates of radiolytic nitrite and nitro radicals in the two systems. Reillex{trademark} HPQ resin provided the greatest radiation stability, whereas Lewatit{trademark} MP-500-FK was the least stable of the resins tested. Thermogravimetric analyses of dry, nitrate-form resin revealed that dry Reillex{trademark} HPQ resin offered the best thermal stability for absorbed gamma doses to 370 megarads, but the worst thermal stability after exposures of 550 megarads or more. 25 refs., 11 figs., 13 tabs.

  8. Evaluating ion exchange resin efficiency and oxidative capacity for the separation of uranium(IV) and uranium(VI)

    PubMed Central

    2013-01-01

    Background Previously described methods to separate dissolved U(IV) from dissolved U(VI) under acidic anoxic conditions prior to laboratory analysis were ineffective with materials currently available commercially. Three strong anion exchange resins were examined for their efficiency in separating, recovering, and preserving both redox states during separation. Results Under oxic conditions, recovery of U(VI) from three exchange resins (Bio-Rad AG® 1x8 Poly-Prep® prefilled columns, Bio-Rad AG® 1x8 powder, and Dowex® 1x8 powder) ranged from 72% to 100% depending on the dosed mass, eluent volume, and resin selected. Dowex® 1x8 resin was the only resin found to provide 100% recovery of U(VI) with fewer than 5 bed volumes of eluent. Under anoxic conditions, all three resins oxidized U(IV) in aqueous solutions with relatively low U(IV) concentrations (<3x10-6 M). Resin-induced oxidation was observed visually using a leuco dye, safranin-o. Oxidants associated with the resin were irreversibly reduced by the addition of Ti(III). After anoxic resin pre-treatment, a series of U(IV)/U(VI) mixtures at micro-molar levels were prepared and separated using the Dowex® 1x8 resin with 100% recovery of both U(IV) and U(VI) with no resin-induced changes in oxidation state. Conclusions Currently available anion exchange resins with apparently identical physical properties were found to have significantly different recoveries for hexavalent uranium at micro-molar concentrations. A novel qualitative technique was developed to visually assess oxidative capacities of anion exchange resins under acidic anoxic conditions. A protocol was developed for pre-treatment and use of currently available anion exchange resins to achieve quantitative separation of U(IV) and U(VI) in aqueous solutions with low U(IV) concentrations. This method can be applied to future work to quantitatively assess dissolved U(IV) and U(VI) concentrations in both laboratory and field samples. PMID:23363052

  9. InGaN power laser chips in a novel 50W multi-die package

    NASA Astrophysics Data System (ADS)

    Loeffler, Andreas; Eichler, Christoph; Mueller, Jens; Gerhard, Sven; Stojetz, Bernhard; Tautz, Soenke; Vierheilig, Clemens; Ristic, Jelena; Avramescu, Adrian; Horn, Markus; Hager, Thomas; Walter, Christoph; Dobbertin, Thomas; Koenig, Harald; Strauss, Uwe

    2015-03-01

    In this paper we report recent developments on high power blue laser chips. Reduction of internal losses as well as optimized thermal management had been essential to increase optical output power. R and D samples with average performance of 3W optical output at junction temperatures of 130°C are demonstrated. The chips are suitable for use in a novel multi chip housing: For the first time up to 20 blue laser chips have been packaged into one compact housing resulting in the first InGaN laser device with optical output > 50W. The highly integrated package offers a unique small size. The outer dimensions of the package are 25.5mm x 35mm with an emitting surface of 16mm x 16.5mm. Therefore the complexity of optical alignment is dramatically reduced and only a single sheet multi lens array is required for beam collimation. Besides the unique technical performance the multi-die package offers significantly lower assembly costs because of the reduced complexity and assembly time. The butterfly package contains 4 bars with up to 5 multimode laser chips in series connection on each bar operating at 2.3A. The typical module wavelength is 450nm +/- 10nm. At a case temperature of 50°C the R and D samples achieve efficiencies of typ. 30% and an optical output power of 50W corresponding to an electrical power consumption of ~165W. This new technology can be used for high performance light engines of high brightness projectors.

  10. Fractionation of NaCl, MgCl2, and CaCl2 brines with a polyfunctional ion exchange resin 

    E-print Network

    Baker, Albert Byre

    1959-01-01

    (Dowex-l). Acryl1c acid has been polymerized ins1de the resin matrix giving the resin cationic exchange properties in addition to 1ts an1on1c exchange propert1es. The particular resin used in this work has equiva- lent quaternary ammonium (anionic... showing the effect of flow rate, column geometry, volume ratios and other factors on the separations obtained. Cohn and Kohn (4) applied the methods of Mayer and Tompkins to the separation of the alkali metals. They used a sulfonated polystyrene cation...

  11. Evaluation and application of anion exchange resins to measure groundwater uranium flux at a former uranium mill site.

    PubMed

    Stucker, Valerie; Ranville, James; Newman, Mark; Peacock, Aaron; Cho, Jaehyun; Hatfield, Kirk

    2011-10-15

    Laboratory tests and a field validation experiment were performed to evaluate anion exchange resins for uranium sorption and desorption in order to develop a uranium passive flux meter (PFM). The mass of uranium sorbed to the resin and corresponding masses of alcohol tracers eluted over the duration of groundwater installation are then used to determine the groundwater and uranium contaminant fluxes. Laboratory based batch experiments were performed using Purolite A500, Dowex 21K and 21K XLT, Lewatit S6328 A resins and silver impregnated activated carbon to examine uranium sorption and extraction for each material. The Dowex resins had the highest uranium sorption, followed by Lewatit, Purolite and the activated carbon. Recoveries from all ion exchange resins were in the range of 94-99% for aqueous uranium in the environmentally relevant concentration range studied (0.01-200 ppb). Due to the lower price and well-characterized tracer capacity, Lewatit S6328 A was used for field-testing of PFMs at the DOE UMTRA site in Rifle, CO. The effect on the flux measurements of extractant (nitric acid)/resin ratio, and uranium loading were investigated. Higher cumulative uranium fluxes (as seen with concentrations>1 ug U/gram resin) yielded more homogeneous resin samples versus lower cumulative fluxes (<1 ug U/gram resin), which caused the PFM to have areas of localized concentration of uranium. Resin homogenization and larger volume extractions yield reproducible results for all levels of uranium fluxes. Although PFM design can be improved to measure flux and groundwater flow direction, the current methodology can be applied to uranium transport studies. PMID:21798572

  12. Diclofenac removal in urine using strong-base anion exchange polymer resins.

    PubMed

    Landry, Kelly A; Boyer, Treavor H

    2013-11-01

    One of the major sources of pharmaceuticals in the environment is wastewater effluent of which human urine contributes the majority of pharmaceuticals. Urine source separation has the potential to isolate pharmaceuticals at a higher concentration for efficient removal as well as produce a nutrient byproduct. This research investigated the efficacy of using strong-base anion exchange polymer resins to remove the widely detected and abundant pharmaceutical, diclofenac, from synthetic human urine under fresh and ureolyzed conditions. The majority of experiments were conducted using a strong-base, macroporous, polystyrene resin (Purolite A520E). Ion-exchange followed a two-step removal rate with rapid removal in 1 h and equilibrium removal in 24 h. Diclofenac removal was >90% at a resin dose of 8 mL/L in both fresh and ureolyzed urine. Sorption of diclofenac onto A520E resin was concurrent with desorption of an equivalent amount of chloride, which indicates the ion-exchange mechanism is occurring. The presence of competing ions such as phosphate and citrate did not significantly impact diclofenac removal. Comparisons of three polystyrene resins (A520E, Dowex 22, Dowex Marathon 11) as well as one polyacrylic resin (IRA958) were conducted to determine the major interactions between anion exchange resin and diclofenac. The results showed that polystyrene resins provide the highest level of diclofenac removal due to electrostatic interactions between quaternary ammonium functional groups of resin and carboxylic acid of diclofenac and non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Diclofenac was effectively desorbed from A520E resin using a regeneration solution that contained 4.5% (m/m) NaCl in an equal-volume mixture of methanol and water. The greater regeneration efficiency of the NaCl/methanol-water mixture over the aqueous NaCl solution supports the importance of non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Experiments with ketoprofen, in addition to diclofenac, suggest that polystyrene anion exchange resins can be used to selectively remove other acidic pharmaceuticals from urine. PMID:24029637

  13. Photocatalysis of chloroform decomposition by tetrachlorocuprate (II) on Dowex 2-X8.

    PubMed

    Harvey, Brent M; Hoggard, Patrick E

    2014-01-01

    Heterogenized on a polystyrene anion exchange resin and in the presence of oxygen, CuCl4(2-) catalyzes the photodecomposition of chloroform at wavelengths above 345 nm with greater efficiency than an equivalent amount in homogeneous solution. The reaction is proposed to proceed in two stages, the first stage yielding CCl4 and HO2(-) as products, the second consisting of a chain reaction resulting from the CuCl4(2-)-catalyzed photodissociation of CCl4, yielding phosgene with CCl3 radicals as chain carriers. Photodecomposition is retarded by added Cl(-), CH3CN, C6H12 or C2H5OH, which is ascribed to the displacement of CHCl3 molecules from the vicinity of the copper by attraction to the polystyrene matrix or to the alkylammonium cation sites. PMID:25155803

  14. 50-W LTCC Transmitter Utilizing 28-V GaAs With Integrated High-Speed Pulse Modulation

    Microsoft Academic Search

    Christopher T. Rodenbeck; Richard T. Knudson; Charles E. Sandoval; Kenneth A. Peterson; Jeffrey M. Pankonin; Robert Eye; Donald Allen; Gailon Brehm; Richard Binney; Frank Smith; Jeffrey W. Dimsdle

    2009-01-01

    This letter presents an S-band 50-W low-temperature cofired ceramic (LTCC) transmitter module. The module is based on a gallium arsenide (GaAs) chipset that operates over the 2-3 GHz range and includes a 28-V single-chip power amplifier with integrated high-speed drain modulator. The transmitter has rise\\/fall times < 7 nsec, linear frequency tuning, and excellent thermal performance.

  15. Resin Chemistry

    Microsoft Academic Search

    Louis Pilato

    2010-01-01

    \\u000a During the ensuing years since the last phenolic resins book was published, many new and remarkable developments have occurred\\u000a in the realm of phenolic chemistry and are given in this chapter.\\u000a \\u000a \\u000a A critical examination of the first step or addition step (methylolation) in the preparation of resoles is described and how\\u000a it can be controlled and compared with the typical

  16. Cobalt preconcentration on a nitroso-R salt functional resin and elution with titanium(III)

    SciTech Connect

    Stella, R.; Valentini, M.T.G.; Maggi, L.

    1985-08-01

    The anion exchange resin Dowex 1X8, converted to the nitroso-R salt form, was used for adsorbing cobalt from large freshwater samples. Strongly acid titanium(III) chloride 10/sup -2/ M solution was found very effective at 60/sup 0/C as a new eluant and yielded complete recovery with a preconcentration factor of 100. Subsequent atomic absorption spectrometry determination of cobalt in the eluate was possible with no interference from titanium, reduced organics, and iron, copper, and nickel which partially might be fixed onto the resin. The suggested procedure allows a reproducibility of 5-10% for samples with cobalt concentrations in the range of 0.01-1 ..mu..g L/sup -1/. 15 references, 2 figures, 3 tables.

  17. Phenolic resin syntactic foams

    SciTech Connect

    McIlroy, H.M.

    1980-06-01

    Syntactic foams were prepared from blends of six phenolic resins and carbon microbubbles. The compressive strength of the phenolic resin foams is equivalent to the strength of foams made from a polyimide resin. Ammonia evolved during the cure diffuses rapidly and is not bound by the foam.

  18. Denture base resins.

    PubMed

    Winkler, S

    1984-04-01

    Numerous investigations have concluded that the conventional acrylic resins, processed with the usual technique of compression molding, produce dentures that are just as stable in dimension and as satisfactory as dentures produced with special resins and elaborate processing equipment. The physical properties of injection molded dentures are not superior to those of acrylic resin dentures produced by the usual carefully controlled compression molding techniques. Cold-curing acrylic resins produce dentures that are as satisfactory as those made from heat-curing resins. PMID:6373408

  19. Oxazoline polyester coating resins

    Microsoft Academic Search

    W. J. deJarlais; L. E. Gast; J. C. Cowan

    1967-01-01

    Oxazoline polyester resins were prepared by reaction of oxazoline diols from linseed acids and tris (hydroxymethyl) aminomethane\\u000a with each of five dibasic acids (adipic, dimer, fumaric, itaconic and maleic). Certain resins were dissolved in isopropyl\\u000a alcohol to give solutions infinitely water dilutable when the free carboxyl was neutralized with an amine. Film properties\\u000a of resins cast on steel plates were

  20. Delayed cure bismaleimide resins

    DOEpatents

    Not Available

    1982-08-12

    Prior art polybismaleimides begin to polymerize at or just above the melting point of the monomer. This patent describes new bismaleimide resins which have an increased pot life and provide longer time periods in which the monomer remains fluid. The resins can be polymerized into molded articles with a high uniformity of properties. (DLC)

  1. Development of resins for composites by resin transfer molding

    NASA Technical Reports Server (NTRS)

    Woo, Edmund P.; Puckett, Paul M.; Maynard, Shawn J.

    1991-01-01

    Designed to cover a wide range of resin technology and to meet the near-term and long-term needs of the aircraft industry, this research has three objectives: to produce resin transfer molding (RES) resins with improved processability, to produce prepreg systems with high toughness and service temperature, and to produce new resin systems. Progress on reaching the objectives is reported.

  2. Simultaneous determination of cobalt, copper and zinc by energy dispersive X-ray fluorescence spectrometry after preconcentration on PAR-loaded ion-exchange resin.

    PubMed

    Jiang, Zi-Tao; Yu, Jimmy C; Liu, Ho-Yan

    2005-07-01

    A sensitive method for the preconcentration and determination of trace amounts of Co, Cu and Zn by energy-dispersive X-ray fluorescence spectrometry (EDXRF) has been developed. The method is based on the fact that 4-(2-pyridylazo)-resorcinol (PAR) loaded Dowex anion-exchange resin (PAR-resin) can effectively adsorb Co, Cu and Zn at pH 9.0 to form PAR-metal complexes. The detection limits for Co, Cu and Zn were 1.53, 0.31 and 0.21 ppb, respectively. The precisions for five replicate measurements of the three metals were 3.4, 2.7 and 2.1% RSD, and the calibration curves were linear up to 75 microg with correlation coefficients of 0.9975, 0.9980 and 0.9985, respectively. The method was successfully applied for the simultaneous determination of Co, Cu and Zn in seawater samples at ppb levels. PMID:16038508

  3. Biocidal quaternary ammonium resin

    NASA Technical Reports Server (NTRS)

    Janauer, G. E.

    1983-01-01

    Activated carbon (charcoal) and polymeric resin sorbents are widely used in the filtration and treatment of drinking water, mainly to remove dissolved organic and inorganic impurities and to improve the taste. Earlier hopes that activated carbon might "disinfect' water proved to be unfounded. The feasibility of protecting against microbial infestation in charcoal and resin beds such as those to be incorporated into total water reuse systems in spacecraft was investigated. The biocidal effect of IPCD (insoluable polymeric contact disinfectants) in combination with a representative charcoal was assessed. The ion exchange resins (IPCD) were shown to adequately protect charcoal and ion exchange beds.

  4. Biocompatibility of composite resins

    PubMed Central

    Mousavinasab, Sayed Mostafa

    2011-01-01

    Dental materials that are used in dentistry should be harmless to oral tissues, so they should not contain any leachable toxic and diffusible substances that can cause some side effects. Reports about probable biologic hazards, in relation to dental resins, have increased interest to this topic in dentists. The present paper reviews the articles published about biocompatibility of resin-restorative materials specially resin composites and monomers which are mainly based on Bis-GMA and concerns about their degradation and substances which may be segregated into oral cavity. PMID:23372592

  5. Acetylene terminated matrix resins

    NASA Technical Reports Server (NTRS)

    Goldfarb, I. J.; Lee, Y. C.; Arnold, F. E.; Helminiak, T. E.

    1985-01-01

    The synthesis of resins with terminal acetylene groups has provided a promising technology to yield high performance structural materials. Because these resins cure through an addition reaction, no volatile by-products are produced during the processing. The cured products have high thermal stability and good properties retention after exposure to humidity. Resins with a wide variety of different chemical structures between the terminal acetylene groups are synthesized and their mechanical properties studied. The ability of the acetylene cured polymers to give good mechanical properties is demonstrated by the resins with quinoxaline structures. Processibility of these resins can be manipulated by varying the chain length between the acetylene groups or by blending in different amounts of reactive deluents. Processing conditions similar to the state-of-the-art epoxy can be attained by using backbone structures like ether-sulfone or bis-phenol-A. The wide range of mechanical properties and processing conditions attainable by this class of resins should allow them to be used in a wide variety of applications.

  6. Influence of co-ions in the eluent on the separation factor of lithium isotopes

    Microsoft Academic Search

    D. W. Kim; G. S. Lee

    1991-01-01

    The influence of co-ions in the eluent on the separation factor () of lithium isotope separation has been studied by ion exchange chromatography. A strongly acid cation exchange resin (Dowex 50W-X8) was used for the separation of lithium isotopes. The co-ions used in eluent were H+, K+, Ba2+, Cu2+, Al3+ and Cr3+ as their chlorides. From the experiments, it was

  7. Calcium isotope fractionation in ion-exchange chromatography

    Microsoft Academic Search

    W. A. Russell; D. A. Papanastassiou

    1978-01-01

    Significant fractionation of the isotopes of calcium has been observed during elution through short ion-exchange columns packed with Dowex 50W-X8 resin. A double isotopic tracer was used to provide correction for instrumental fractionation effects. The absolute ⁴°Ca\\/⁴⁴Ca ratio is determined by this method to 0.05% and provides a measure of the fractionation of all Ca isotopes. It is found that

  8. Emission spectrographic determination of barium in sea water using a cation exchange concentration procedure

    USGS Publications Warehouse

    Szabo, B. J.; Joensuu, O.

    1967-01-01

    A concentration technique employing Dowex 50W cation exchange resin is described for the determination of barium in sea water. The separated barium is precipitated as fluoride together with calcium and strontium and measured by emission spectrographic analysis. The vertical distribution of barium in sea water has been measured in the Caribbean Sea and the Atlantic Ocean. The barium content varied between 7 and 23 ??g. per liter; in two profiles, the lowest concentrations were at a depth of about 1000 meters.

  9. Graphite fiber reinforced thermoplastic resins

    NASA Technical Reports Server (NTRS)

    Novak, R. C.

    1975-01-01

    Mechanical properties of neat resin samples and graphite fiber reinforced samples of thermoplastic resins were characterized with particular emphasis directed to the effects of environmental exposure (humidity, temperature and ultraviolet radiation). Tensile, flexural, interlaminar shear, creep and impact strengths were measured for polysulfone, polyarylsulfone and a state-of-the-art epoxy resin samples. In general, the thermoplastic resins exhibited environmental degradation resistance equal to or superior to the reference epoxy resin. Demonstration of the utility and quality of a graphite/thermoplastic resin system was accomplished by successfully thermoforming a simulated compressor blade and a fan exit guide vane.

  10. Effects of blood contamination on resin–resin bond strength

    Microsoft Academic Search

    Sigurdur O Eiriksson; Patricia N. R Pereira; Edward J Swift; Harald O Heymann; Asgeir Sigurdsson

    2004-01-01

    Objective. Incremental placement and curing of resin composites has been recommended. However, this requires longer operating time, and therefore, increased risk of contamination. The purpose of this study was to evaluate the effects of blood contamination on microtensile bond strengths (?TBS) between resin interfaces and to determine the best decontamination method to re-establish the original resin–resin bond strength.Materials. The top

  11. Method for removing contaminants from plastic resin

    DOEpatents

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2008-12-09

    A resin recycling method that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The method includes receiving the resin in container form. The containers are then ground into resin particles. The particles are exposed to a solvent, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. After separating the particles and the resin, a solvent removing agent is used to remove any residual solvent remaining on the resin particles after separation.

  12. Resin impregnation process for producing a resin-fiber composite

    NASA Technical Reports Server (NTRS)

    Palmer, Raymond J. (Inventor); Moore, William E. (Inventor)

    1994-01-01

    Process for vacuum impregnation of a dry fiber reinforcement with a curable resin to produce a resin-fiber composite, by drawing a vacuum to permit flow of curable liquid resin into and through a fiber reinforcement to impregnate same and curing the resin-impregnated fiber reinforcement at a sufficient temperature and pressure to effect final curing. Both vacuum and positive pressure, e.g. autoclave pressure, are applied to the dry fiber reinforcement prior to application of heat and prior to any resin flow to compact the dry fiber reinforcement, and produce a resin-fiber composite of reduced weight, thickness and resin content, and improved mechanical properties. Preferably both a vacuum and positive pressure, e.g. autoclave pressure, are also applied during final curing.

  13. Nontoxic Resins Advance Aerospace Manufacturing

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The 2008 NASA Commercial Invention of the Year, PETI-330, is a polyimide matrix resin that performs well at high temperatures and is easily processed into composites in a simple, short curing cycle. Invented by scientists at Langley Research Center, PETI-330 is now licensed to Ube Industries, based in Japan with its American headquarters in New York. In addition to being durable and lightweight, the resin is also nontoxic, which makes it safe for workers to handle. PETI-330 was created specifically for heat-resistant composites formed with resin transfer molding and resin infusion, which formerly could only be used with low temperature resin systems.

  14. High-COMD nitridized InAlGaAs laser facets for high-reliability 50-W bar operation at 805 nm

    NASA Astrophysics Data System (ADS)

    Silfvenius, Christofer; Blixt, Peter; Lindstrom, Carsten; Feitisch, Alfred O.

    2004-06-01

    The 40-year-old laser diode technology underpins applications such as data storage, industrial lasers and telecommunications but still suffers from reliability and longevity issues in high power applications, most notably in pumping of Nd:YVO4 and Nd:YAG lasers. Despite thermal advantages allowing expansion matched Au/Sn hard soldering, the main problem for InAlGaAs lasers is facet oxidation, which leads to increased absorption and COMD device failure. This article presents a novel process, which atomically seals the surface and eliminates oxidation by forming stable nitrides on the facet. Pulsed testing of 805 nm of Al>0.20InGaAs single mode devices with a protective nitride layer demonstrates stable median 1.3W COMD (30MW/cm2), after one hour of CW screening at 12.5mW/?m (50W bar power). A 200h burn-in at 12.5mW/?m (50W bar power) resulted in an initial power drop of 1-2% and a linear degradation rate of 0.1%/1000h, compared to an initial power drop of 5-18% and a degradation rate of 46%/1000h for lasers with only AR/HR-coatings. A subsequent 1000h life-test at 22.5mW/um (90W bar power) demonstrated a degradation rate of only 3%/1000h under stress test conditions due to p-side up mounting, 10°C higher ambient temperature and 57% higher operating current over typical high power bar operating power levels. The QW temperature was 53°C. No sudden device failures occurred.

  15. Resin composite restorative materials.

    PubMed

    Ilie, N; Hickel, R

    2011-06-01

    This paper surveys the most important developments in resin-based dental composites and focuses on the deficits (e.g. polymerization shrinkage) and strengths of the materials and their clinical implications. Moreover, differences between composite categories, such as hybrid, nanohybrid, microfilled, packable, ormocer-based, silorane-based, polyacid-modified composites (compomers) and flowable composites are highlighted, especially in view of their mechanical behaviour. In addition to the classical dimethacrylate-based composites, special attention is given to alternative monomers, such as siloranes, ormocers or high-molecular-weight dimethacrylate monomers (e.g. dimer acid-based dimethacrylates and tricyclodecane (TCD)-urethane), analysing their advantages, behaviour and abilities. Finally, the paper attempts to establish the needs and wishes of clinicians for further development of resin-based composites. PMID:21564116

  16. Flame Retardant Epoxy Resins

    NASA Technical Reports Server (NTRS)

    Thompson, C. M.; Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.; Lyon, R. E.

    2004-01-01

    As part of a program to develop fire resistant exterior composite structures for future subsonic commercial aircraft, flame retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured epoxies were characterized by thermogravimetric analysis, propane torch test, elemental analysis and microscale combustion calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness of plaques of several cured formulations was determined on single-edge notched bend specimens. The chemistry and properties of these new epoxy formulations are discussed.

  17. System for removing contaminants from plastic resin

    DOEpatents

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2010-11-23

    A resin recycling system that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The system includes receiving the resin in container form. A grinder grinds the containers into resin particles. The particles are exposed to a solvent in one or more solvent wash vessels, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. A separator is used to separate the resin particles and the solvent. The resin particles are then placed in solvent removing element where they are exposed to a solvent removing agent which removes any residual solvent remaining on the resin particles after separation.

  18. Vitrification of ion exchange resins

    DOEpatents

    Cicero-Herman, Connie A. (Aiken, SC); Workman, Rhonda Jackson (North Augusta, SC)

    2001-01-01

    The present invention relates to vitrification of ion exchange resins that have become loaded with hazardous or radioactive wastes, in a way that produces a homogenous and durable waste form and reduces the disposal volume of the resin. The methods of the present invention involve directly adding borosilicate glass formers and an oxidizer to the ion exchange resin and heating the mixture at sufficient temperature to produce homogeneous glass.

  19. 21 CFR 178.3930 - Terpene resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...3 2014-04-01 2014-04-01 false Terpene resins. 178.3930 Section 178.3930 Food and...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

  20. 21 CFR 178.3930 - Terpene resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...3 2013-04-01 2013-04-01 false Terpene resins. 178.3930 Section 178.3930 Food and...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

  1. 21 CFR 178.3930 - Terpene resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...3 2011-04-01 2011-04-01 false Terpene resins. 178.3930 Section 178.3930 Food and...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

  2. 21 CFR 178.3930 - Terpene resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 3 2010-04-01 2009-04-01 true Terpene resins. 178.3930 Section 178.3930 Food and...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

  3. 21 CFR 178.3930 - Terpene resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...3 2012-04-01 2012-04-01 false Terpene resins. 178.3930 Section 178.3930 Food and...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

  4. Indirect resin composites

    PubMed Central

    Nandini, Suresh

    2010-01-01

    Aesthetic dentistry continues to evolve through innovations in bonding agents, restorative materials, and conservative preparation techniques. The use of direct composite restoration in posterior teeth is limited to relatively small cavities due to polymerization stresses. Indirect composites offer an esthetic alternative to ceramics for posterior teeth. This review article focuses on the material aspect of the newer generation of composites. This review was based on a PubMed database search which we limited to peer-reviewed articles in English that were published between 1990 and 2010 in dental journals. The key words used were ‘indirect resin composites,’ composite inlays,’ and ‘fiber-reinforced composites.’ PMID:21217945

  5. Imide modified epoxy matrix resins

    NASA Technical Reports Server (NTRS)

    Scola, D. A.; Pater, R. H.

    1981-01-01

    High char yield epoxy using novel bisimide amines (BIA's) as curing agents with a state of the art epoxy resin was developed. Stoichiometric quantities of the epoxy resin and the BIA's were studied to determine the cure cycle required for preparation of resin specimens. The bisimide cured epoxies were designated IME's (imide modified epoxy). The physical, thermal and mechanical properties of these novel resins were determined. The levels of moisture absorption exhibited by the bisimide amine cured expoxies (IME's) were considerably lower than the state of the art epoxies. The strain-to-failure of the control resin system was improved 25% by replacement of DDS with 6F-DDS. Each BIA containing resin exhibited twice the char yield of the control resin MY 720/DDS. Graphite fiber reinforced control (C) and IME resins were fabricated and characterized. Two of the composite systems showed superior properties compared to the other Celion 6000/IME composite systems and state of the art graphite epoxy systems. The two systems exhibited excellent wet shear and flexural strengths and moduli at 300 and 350 F.

  6. Chemoviscosity modeling for thermosetting resins

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Hou, T. H.; Bai, J. M.

    1985-01-01

    A chemoviscosity model, which describes viscosity rise profiles accurately under various cure cycles, and correlates viscosity data to the changes of physical properties associated with structural transformations of the thermosetting resin system during cure, was established. Work completed on chemoviscosity modeling for thermosetting resins is reported.

  7. High performance phenolic pultrusion resin

    SciTech Connect

    Qureshi, S.P.; Ingram, W.H. [Georgia-Pacific Resins, Inc., Decatur, GA (United States); Smith, C. [Morrison Molded Fiber Glass, Bristol, VA (United States)

    1996-11-01

    Today, Phenol-Formaldehyde (PF) resins are the materials of choice for aerospace interior applications, primarily due to low FST (flame, smoke and toxicity). Since 1990, growth of PF resins has been steadily increasing in non-aerospace applications (which include mass transit, construction, marine, mine ducting and offshore oil) due to low FST and reasonable cost. This paper describes one component phenol-formaldehyde resin that was jointly developed with Morrison Molded Fiber Glass for their pultrusion process. Physical properties of the resin with flame/smoke/toxicity, chemical resistance and mechanical performance of the pultruded RP are discussed. Neat resin screening tests to identify high-temperature formulations are explored. Research continues at Georgia-Pacific to investigate the effect of formulation variables on processing and mechanical properties.

  8. Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments

    PubMed Central

    Celik, Cigdem; Cehreli, Sevi Burcak; Arhun, Neslihan

    2015-01-01

    Objective: The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. Materials and Methods: A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the restorations were removed out leaving only middle part. One side of the cavity was finished with course diamond bur and the other was air-abraded with 50 ?m Al2O3. They were randomly divided into four groups (n = 10) to receive: Group 1: Adper Single Bond 2; Group 2: All Bond 3; Group 3: ClearfilSE; Group 4: BeautiBond, before being repaired with the same resin composite (Filtek Z250). The specimens were re-thermocycled (1000×), sealed with nail varnish, stained with 0.5% basic fuchsin, sectioned mesiodistally and photographed digitally. The extent of dye penetration was measured by image analysis software (ImageJ) for both bur-finished and air-abraded surfaces at resin-tooth and resin-resin interfaces. The data were analyzed statistically. Results: BeautiBond exhibited the most microleakage at every site. Irrespective of adhesive and initial composite type, air-abrasion showed less microleakage except for BeautiBond. The type of initial repaired restorative material did not affect the microleakage. BeautiBond adhesive may not be preferred in resin composite repair in terms of microleakage prevention. Conclusions: Surface treatment with air-abrasion produced the lowest microleakage scores, independent of the adhesive systems and the pre-existing resin composite type. Pre-existing composite type does not affect the microleakage issue. All-in-one adhesive resin (BeautiBond) may not be preferred in resin composite repair in terms of microleakage prevention. PMID:25713491

  9. Resin reinforced expansion anchor system

    SciTech Connect

    Clark, C.A.; Wright, R.L.

    1988-08-16

    An expansion anchor assembly is described in combination with a dual compartment resin and cartridge inserted into a mine roof opening, the anchor assembly including: (a) an elongated bolt having a head at one end and threaded for a portion of its length at the other end; (b) an expansion member engaged with the threaded end of the bolt; (c) the expansion member including an expansion shell having a plurality of leaf segments; (d) a first means for engaging the expansion shell with the elongated bolt; (e) a wedge threaded on the elongated bolt for engagement with the expansion shell to urge the latter into gripping engagement with the mine roof; (f) a first resin passageway means on the outer surface of the wedge for permitting resin to gravitate therethrough; (g) the leaf segments of the expansion shell being separated to form a second resin passageway means aligned with the first resin passageway means, whereby resin may gravitate downwardly through substantially the entire length of the assembly, and (h) a second means within the first passageway and engageable with one of the leaf segments to prevent relative rotation of the wedge member with respect to the expansion shell; (i) the resin being mixed upon rotation of the bolt and expansion member and gravitating downwardly through the first and second passageway means into engagement with that portion of the mine roof defining the mine roof opening.

  10. DIRECT ADAPTIVE CONTROL OF RESIN TRANSFER MOLDING

    E-print Network

    Mamishev, Alexander

    . ABSTRACT Resin Transfer Molding (RTM) is a manufacturing process that involves injection of liquid resin involves injection of a liquid resin into a closed mold cavity containing preset fiber mats (also calledDIRECT ADAPTIVE CONTROL OF RESIN TRANSFER MOLDING B. Minaie1,* , W. Li, J. Gou1 , Y. Chen2 , A

  11. Process analysis of compression resin transfer molding

    Microsoft Academic Search

    Prabhas Bhat; Justin Merotte; Pavel Simacek; Suresh G. Advani

    2009-01-01

    Compression resin transfer molding process (CRTM) combines features of compression molding with traditional Resin Transfer Molding (RTM). The CRTM process is described in three stages, with resin being injected into the gap in Stage I, closing of the gap in Stage II and actual compression of preform and re-distribution of the resin in Stage III. To fabricate a void free

  12. Constraints on monitoring resin flow in the resin transfer molding (RTM) process by using thermocouple sensors

    Microsoft Academic Search

    Goker Tuncol; Murat Danisman; Alper Kaynar; E. Murat Sozer

    2007-01-01

    In this study, a thermocouple sensor system was used to monitor the resin transfer molding (RTM) process. These sensors are low-cost and durable; and they do not disturb the resin flow. They can be used if the inlet resin is either hotter or colder than the mold walls. In experiments of this study, much of the hot resin’s internal energy

  13. Radiofrequency activation of epoxy resins

    SciTech Connect

    Palumbo, M.; Vallet, Y.; Alazard, P. [Ecole Nationale Superieure de Chimie de Toulouse (France)

    1995-12-01

    A DGEBA epoxy resin in presence of Diaminodiphenylmethane used as curing agent is crosslinked under radiofrequency (27.12 MHz) irradiation, at given electrical power or voltage. The mechanisms of the polymerization reaction are explained through the study of the time dependence of the electrical parameters and of the average temperature of the chemical medium. The determination of the glassy transition temperatures of the polymeric networks, initial and stabilized after intensive postcure, respectively correlated with the extent of conversion of the epoxy resin and the structural homogeneity shows that the radiofrequency irradiation is as efficient as the microwaves as for the activation of the cure of the epoxy resins.

  14. Resin/graphite fiber composites

    NASA Technical Reports Server (NTRS)

    Cavano, P. J.; Jones, R. J.; Vaughan, R. W.

    1972-01-01

    High temperature resin matrices suitable for use in advanced graphite fiber composites for jet engine applications were evaluated. A series of planned, sequential screening experiments with resin systems in composite form were performed to reduce the number of candidates to a single A-type polyimide resin that repetitively produced void-free, high strength and modulus composites acceptable for use in the 550 F range for 1000 hours. An optimized processing procedure was established for this system. Extensive mechanical property studies characterized this single system, at room temperature, 500 F, 550 F and 600 F, for various exposure times.

  15. Grafted methylenediphosphonate ion exchange resins

    DOEpatents

    Trochimcznk, A.W.; Gatrone, R.C.; Alexandratos, S.; Horwitz, E.P.

    1997-04-08

    An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorus. The pendent groups have the formula as shown in the patent wherein R is hydrogen, a cation or mixtures thereof; and R{sup 1} is hydrogen or an C{sub 1}-C{sub 2} alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange resin are also disclosed.

  16. Alternative alloys for resin-bonded retainers.

    PubMed

    Lawson, J R

    1991-01-01

    Traditionally, resin-bonded fixed partial dentures have been made with nickel-chrome-beryllium alloys and cemented with conventional resin luting cements. However, alternative alloys for resin-bonded retainers offer improved physical and biocompatible properties, and resin-metal bond strengths twice that of traditional methods can be achieved. The superior bonds obtained with etched base metals bonded with adhesive resins and silica-coated alloys bonded with silane-coupling agents make these the most desirable techniques available. PMID:2033556

  17. Phenoxy Resins Containing Pendent Ethynyl Groups

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.

    1986-01-01

    Ethynyl-containing phenoxy resins have excellent shelf life in solution or in bulk. Cured ethynyl-containing phenoxy resins offer lower moisture absorption, higher use temperatures, and better thermal stability over stateof-the-art cross-linked phenoxy resins. Depending upon cross-link density, cured ethynyl-modified phenoxy resins are solvent resistant but still thermoformable and relatively tough. Modified resins show potential for use as adhesives, composite matrices, solvent-resistant coatings, membranes, insulators, and films.

  18. Retrofit for Plastic Resin Driers 

    E-print Network

    Joseph, B.; Thuro, G.

    1991-01-01

    Plastic resins used in injection molding have to be dried to specified levels prior to feeding them to the molding machines. Excess moisture if present could cause damage to the injection nozzle and also could cause polymer degradations within...

  19. Silicone resins and their composites

    E-print Network

    Wu, Yuhong, 1972-

    2003-01-01

    Addition cure (X1-2672) and condensation cure (4-3136) silicone resins have been studied for their mechanical property change with temperature. Properties include maximum flexural stress, flexural modulus and fracture ...

  20. Liquid monobenzoxazine based resin system

    DOEpatents

    Tietze, Roger; Nguyen, Yen-Loan; Bryant, Mark

    2014-10-07

    The present invention provides a liquid resin system including a liquid monobenzoxazine monomer and a non-glycidyl epoxy compound, wherein the weight ratio of the monobenzoxazine monomer to the non-glycidyl epoxy compound is in a range of about 25:75 to about 60:40. The liquid resin system exhibits a low viscosity and exceptional stability over an extended period of time making its use in a variety of composite manufacturing methods highly advantageous.

  1. Regenerating Water-Sterilizing Resins

    NASA Technical Reports Server (NTRS)

    Colombo, G. V.; Putnam, D. F.

    1982-01-01

    Iodine-dispensing resin can be regenerated after iodine content has been depleted, without being removed from water system. Resin is used to make water potable by killing bacteria, fungi, and viruses. Regeneration technique may be come basis of water purifier for very long space missions. Enough crystalline iodine for multiple regenerations during mission can be stored in one small cartridge. Cartridge could be inserted in waterline as necessary on signal from iodine monitor or timer.

  2. Guayule resin separation and purification

    E-print Network

    Bajwa, Mohinder P.S.

    1992-01-01

    fraction and reducing the presence of these terpenes to practically non-detectable levels in the polar fraction. A single component, as identified by gas chromatograph (GC) was also effectively extracted from the Texas A&M resins. Saponification... as little as two GC peaks. Chromatography of the resins over silica gel yielded a fraction from which white crystals were obtained. GC analysis showed that these crystals could be a compound of the germacrene family. Column chromatography of the Firestone...

  3. [Composite resin inlays and onlays].

    PubMed

    Vougiouklakis, G; Mountouris, G; Adritsakis, D

    1990-08-01

    The establishment and development of composite resins has led to their use as a posterior restorative material. Although posterior composites have evolved considerably, both clinical studies and experience have confirmed that several problems still remain concerning their clinical properties and the relative complexity of handling the material. In order to resolve these problems, two different manufacturers have introduced composite resin systems for the fabrication of direct or indirect resin inlays and onlays which are cemented into the acid-etched preparation with a modified composite resin. Both systems are based on the same concept: the polymerization of the resin takes place out of the mouth in a special oven where a specific heat-curing procedure is followed. There is an essential difference between the two systems. When the direct resin system is used, the inlay is formed and partly light-cured into the tooth preparation, then it is removed for further polymerization. When the indirect system is used the procedure takes place in the lab where the inlay is formed on the die. This article presents both systems, the step-by-step procedure that has been followed in several clinical cases as well as their advantages and disadvantages. PMID:2130341

  4. Maleimide Functionalized Siloxane Resins

    SciTech Connect

    Loy, D.A.; Shaltout, R.M.

    1999-04-01

    Polyorganosiloxanes are a commercially important class of compounds. They exhibit many important properties, including very low glass transition temperatures, making them useful over a wide temperature range. In practice, the polysiloxane polymer is often mixed with a filler material to help improve its mechanical properties. An alternative method for increasing polymer mechanical strength is through the incorporation of certain substituents on the polymer backbone. Hard substituents such as carbonates and imides generally result in improved mechanical properties of polysiloxanes. In this paper, we present the preparation of novel polysiloxane resins modified with hard maleimide substituents. Protected ethoxysilyl-substituted propyl-maleimides were prepared. The maleimide substituent was protected with a furanyl group and the monomer polymerized under aqueous acidic conditions. At elevated temperatures (>120 C), the polymer undergoes retro Diels-Alder reaction with release of foran (Equation 1). The deprotected polymer can then be selectively crosslinked by a forward Diels-Alder reaction (in the presence of a co-reactant having two or more dime functionalities).

  5. 76 FR 4936 - Granular Polytetrafluoroethylene Resin From Italy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-27

    ...Granular Polytetrafluoroethylene Resin From Italy AGENCY: United States International Trade...resin (``granular PTFE resin'') from Italy...duty orders on granular PTFE resin from Italy and Japan (75 FR 67082-67083 and...

  6. Low Melt Viscosity Resins for Resin Transfer Molding

    NASA Technical Reports Server (NTRS)

    Harris, Frank W.

    2002-01-01

    In recent years, resin transfer molding (RTM) has become one of the methods of choice for high performance composites. Its cost effectiveness and ease of fabrication are major advantages of RTM. RTM process usually requires resins with very low melt viscosity (less than 10 Poise). The optimum RTM resins also need to display high thennal-oxidative stability, high glass transition temperature (T(sub g)), and good toughness. The traditional PMR-type polyimides (e.g. PMR-15) do not fit this requirement, because the viscosities are too high and the nadic endcap cures too fast. High T(sub g), low-melt viscosity resins are highly desirable for aerospace applications and NASA s Reusable Launch Vehicle (RLV) program. The objective of this work is to prepare low-melt viscosity polyimide resins for RTM or resin film infusion (RFI) processes. The approach involves the synthesis of phenylethynyl-terminated imide oligomers. These materials have been designed to minimize their melt viscosity so that they can be readily processed. During the cure, the oligomers undergo both chain extension and crosslinking via the thermal polymerization of the phenylethynyl groups. The Phenylethynyl endcap is preferred over the nadic group due to its high curing temperature, which provides broader processing windows. This work involved the synthesis and polymerization of oligomers containing zig-zag backbones and twisted biphenyl structures. Some A-B type precursors which possessed both nitro and anhydride functionality, or both nitro and amine functionality, were also synthesized in order to obtain the well defined oligomers. The resulting zig-zag structured oligomers were then end-capped with 4-phenylethynylphthalic anhydride (PEPA) for further cure. The properties of these novel imide oligomers are evaluated.

  7. Optical properties of composite resins.

    PubMed

    Grajower, R; Wozniak, W T; Lindsay, J M

    1982-09-01

    The translucency and colour of a composite resin are characterized by two wavelength-dependent parameters: the absorption coefficient, K and the scattering coefficient, S. These parameters were calculated according to the Kubelka-Munk (1931) equations for two commercial resins. The calculations were based on reflectance spectra of samples of different thicknesses which were placed on a black and a white background. Employing the values of these parameters, calculated spectra were obtained of samples on the same as well as different backgrounds. The difference between the experimental and the calculated spectra was evaluated in terms of Friele-MacAdam-Chickering (Hemmendinger, 1970) colour differences. The Munsell colour values, corresponding to the spectra were evaluated. It was found that the colour of a resin sample of a specified thickness which is placed on a particular background may be predicted to a fair degree of accuracy from calculations employing the K and S values of the resin and the reflectance spectrum of the background. It has been demonstrated that illuminating the sample at 45 degrees instead of using diffuse illumination, affected the results only to a small extent. The effect of internal reflections at the resin surface on the relfectivity on the sample is discussed. An expression has been derived for computing the reflectivity of a sample on any background from its transmittance and reflectivity on a completely absorbing background. PMID:6957570

  8. Mechanistic modeling of epoxy resins

    SciTech Connect

    Chiao, L. (Lawrence Livermore National Lab., CA (USA))

    1989-06-16

    Epoxy resins are an important class of materials, particularly when used as the matrix for advanced fiber composites. Because material performance is directly related to processing, it is useful to study the cure kinetics of these resins for use in process modeling, design and control. Mechanistic modeling of the cure reactions are shown to offer more flexibility than the empirical rate laws currently used, without being cumbersome or impractical. In this work, amine- catalyzed epoxy reactions are studied. A kinetic model is developed, based on an accepted reaction mechanism, and applied to experimental data from the literature. This model is shown to be able to describe the cure of real-world'' systems, and unlike the empirical rate laws, can account for variations in the resin formulations. Moreover, the mechanistic model, unlike the empirical ones, is capable of estimating the concentrations of linkages formed during the cure reactions. These data offer insight into the cured resin morphology, which determines the chemical and physical properties of the material. A composite cure model is developed using the mechanistic kinetics. Results from the model are compared to experimental data from the literature, and the effects of resin formulation and cure cycle changes are investigated. 29 refs., 10 figs., 3 tabs.

  9. Poisoning of resin supported catalyst

    SciTech Connect

    Hunter, D.L.; Moore, S.E.

    1987-02-10

    A method is described of enhancing performance of a combined hydroformylation/reduction reaction of an olefin liquid feed in the presence of a resin-supported transition metal complex catalyst. The method comprises: (a) preparing a resin-supported transition metal complex catalyst for use in a combined hydroformylation/reduction reaction substantially free of halides and halide salts in the metal complex catalyst; and (b) introducing an olefin liquid feed to the resin-supported catalyst for conducting a combined hydroformylation/reduction reaction, in the presence of CO and H/sub 2/. The olefin feed has a specified maximum limit of halide concentration sufficiently low to enable continued indefinite operation of the combined hydroformylation/reduction reaction process without halide poisoning.

  10. 21 CFR 872.3140 - Resin applicator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin...is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth...

  11. 21 CFR 872.3140 - Resin applicator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin...is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth...

  12. 21 CFR 872.3140 - Resin applicator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin...is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth...

  13. 21 CFR 872.3140 - Resin applicator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin...is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth...

  14. 21 CFR 872.3140 - Resin applicator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin...is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth...

  15. 21 CFR 177.1585 - Polyestercarbonate resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...following specifications: (i) The solution intrinsic viscosity of the polyestercarbonate resins shall be a minimum of 0...per gram, as determined by a method entitled “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

  16. 21 CFR 177.1585 - Polyestercarbonate resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...following specifications: (i) The solution intrinsic viscosity of the polyestercarbonate resins shall be a minimum of 0...per gram, as determined by a method entitled “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

  17. 21 CFR 177.1585 - Polyestercarbonate resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...following specifications: (i) The solution intrinsic viscosity of the polyestercarbonate resins shall be a minimum of 0...per gram, as determined by a method entitled “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by a...

  18. 21 CFR 177.1585 - Polyestercarbonate resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...following specifications: (i) The solution intrinsic viscosity of the polyestercarbonate resins shall be a minimum of 0...per gram, as determined by a method entitled “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

  19. 21 CFR 177.1585 - Polyestercarbonate resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...following specifications: (i) The solution intrinsic viscosity of the polyestercarbonate resins shall be a minimum of 0...per gram, as determined by a method entitled “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

  20. Synthesis and evaluation of actinide imprinted resins

    E-print Network

    Noyes, Karen Lynn, 1977-

    2003-01-01

    Organic resins have previously shown good results with application to actinide separations. Large portions of recent research have been dedicated to the synthesis and evaluation of resins with phenolic-type functional ...

  1. NEW ION EXCHANGE RESIN FOR URANIUM RECOVERY

    Microsoft Academic Search

    A. H. Greer; A. B. Mindler; J. P. Termini

    1958-01-01

    A new resin, developed specifically for U recovery from HâSOâ; leach liquors, is available commercially-- Permutit SK for resin-in-column ; operation and Permutite SKB for resin-in-pulp operation. These resins hnve a ; fast U adsorption rate and a fast and a complete U elution rate. They have good ; physical and chemical stability which will mean a minimum of physical

  2. Siloxane-modified epoxy resins

    Microsoft Academic Search

    E. M. Yorkgitis; N. S. Eiss; C. Tran; G. L. Wilkes; J. E. McGrath

    Epoxy resins chemically modified with functionally terminated poly (dimethyl siloxane), poly(dimethyl-co-methyltrifluoropropyl\\u000a siloxane), and poly(dimethyl-co-diphenyl siloxane) oligomers are described in terms of their synthesis, morphology, solid-state\\u000a properties, and friction and wear properties. The compatibility between the epoxy resin and the siloxane modifiers can be\\u000a enhanced by increasing the percentage of methyltrifluoropropyl (TFP) siloxane or diphenyl (DP) siloxane relative to dimethyl\\u000a siloxane.

  3. Development of a new on-line system for the sequential speciation and determination of chromium species in various samples using a combination of chelating and ion exchange resins.

    PubMed

    ?ahan, Serkan; Saçmac?, ?erife; Kartal, ?enol; Saçmac?, Mustafa; ?ahin, U?ur; Ülgen, Ahmet

    2014-03-01

    A new on-line flow injection (FI) procedure for the sequential separation, preconcentration and speciation of Cr(III)/Cr(VI) species in different matrices is described based on the combining of solid phase extraction and flame atomic absorption spectrometry (FAAS). Poly 2-(5-methylisoxazol)methacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid-co-divinyl-benzene and Dowex 21K resins were used as chelating and ion-exchange materials for the separation/preconcentration of Cr(III) and Cr(VI) ions, respectively. Trace amounts of chromium retained on the resins were eluted sequentially with HNO3 and then introduced directly to the nebulizer-burner system of FAAS. The optimum conditions such as pH of the sample solution, amount of the resin, volume of the sample and interfering ions, which are effective on the quantitative recovery of the analytes, were investigated for sequential determination of Cr(III) and Cr(VI) ions. The preconcentration factors were found to be 48 and 30 for Cr(III) and Cr(VI), and the detection limits corresponding to three times the standard deviation of the blank (3s/b) were 0.05 and 0.3 µg L(-1), respectively. The method was verified by analyzing a certified reference material. The proposed method was applied to the determination based on the speciation of chromium in various real samples with satisfactory results. PMID:24468387

  4. Method for removing contaminants from plastic resin

    DOEpatents

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2008-12-30

    A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

  5. Method of removing contaminants from plastic resins

    DOEpatents

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2008-11-18

    A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

  6. SRM filament wound case resin characterization studies

    NASA Technical Reports Server (NTRS)

    Chou, L. W.

    1985-01-01

    The amine cured epoxy wet winding resin used in fabrication of the SRM filament wound case is analyzed. High pressure liquid chromatography (HPSC) is utilized extensively to study lot-to-lot variation in both resin and curing agent. The validity of quantitative hplc methodology currently under development in-process resin/catalyst assay is assessed.

  7. Method of removing contaminants from plastic resins

    DOEpatents

    Bohnert,George W. (Harrisonville, MO); Hand,Thomas E. (Lee's Summit, MO); Delaurentiis,Gary M. (Jamestown, CA)

    2007-08-07

    A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

  8. 21 CFR 172.280 - Terpene resin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Terpene resin. 172.280 Section 172.280 Food and...Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with...

  9. 21 CFR 172.280 - Terpene resin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Terpene resin. 172.280 Section 172.280 Food and...Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with...

  10. 21 CFR 172.280 - Terpene resin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Terpene resin. 172.280 Section 172.280 Food and...Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with...

  11. 21 CFR 172.280 - Terpene resin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 2009-04-01 true Terpene resin. 172.280 Section 172.280 Food and...Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with...

  12. 21 CFR 172.280 - Terpene resin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 2011-04-01 false Terpene resin. 172.280 Section 172.280 Food and...Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with...

  13. Terpene-anhydride resin based coatings II

    Microsoft Academic Search

    C. L. Giddings; David L. Trumbo

    1997-01-01

    Terpinolene-maleic anhydride or terpinolene-itaconic anhydride resins were used in thermoset coatings crosslinked with an epoxidized soybean oil. As the films produced were brittle, attempts were made to increase the molecular weight of the terpene anhydride resins by using a purer grade of terpinolene monomer or a terpinolene analog, ?-phellandrene, as the terpene part of the resins. The purer grade of

  14. Considering RTM... 1 Considering Resin Transfer Molding?

    E-print Network

    Colton, Jonathan S.

    is closed and clamped; The resin is injected into the mold cavity under pressure. The motive force in RTMConsidering RTM... 1 CFA 1995 Considering Resin Transfer Molding? Here is what you need to know than traditional open molding. Resin Transfer Molding stands in the gap - able to produce mid

  15. Synthesis of improved phenolic resins

    NASA Technical Reports Server (NTRS)

    Delano, C. B.; Mcleod, A. H.

    1979-01-01

    Twenty seven addition cured phenolic resin compositions were prepared and tested for their ability to give char residues comparable to state-of-the-art phenolic resins. Cyanate, epoxy, allyl, acrylate, methacrylate and ethynyl derivatized phenolic oligomers were investigated. The novolac-cyanate and propargyl-novolac resins provided anaerobic char yields at 800 C of 58 percent. A 59 percent char yield was obtained from modified epoxy novolacs. A phosphonitrilic derivative was found to be effective as an additive for increasing char yields. The novolac-cyanate, epoxy-novolac and methacrylate-epoxy-novolac systems were investigated as composite matrices with Thornel 300 graphite fiber. All three resins showed good potential as composite matrices. The free radical cured methacrylate-epoxy-novolac graphite composite provided short beam shear strengths at room temperature of 93.3 MPa (13.5 ksi). The novolac-cyanate graphite composite produced a short beam shear strength of 74 MPa (10.7 ksi) and flexural strength of 1302 MPa (189 ksi) at 177 C. Air heat aging of the novolac-cyanate and epoxy novolac based composites for 12 weeks at 204 C showed good property retention.

  16. Resin transfer molding process optimization

    Microsoft Academic Search

    M. Y. Lin; M. J. Murphy; H. T. Hahn

    2000-01-01

    The art of process optimization requires a clear understanding of the differences between each of the widely different optimization strategies available. Often, a sophisticated method that has been well tested in other fields is not applicable at all to problems in resin transfer molding (RTM). This work discusses the strength and weakness of the genetic algorithm and the gradient based

  17. Oxygen index tests of thermosetting resins

    NASA Technical Reports Server (NTRS)

    Gilwee, W. J., Jr.; Parker, J. A.; Kourtides, D. A.

    1980-01-01

    The flammability characteristics of nine thermosetting resins under evaluation for use in aircraft interiors are described. These resins were evaluated using the Oxygen Index (ASTM 2863) testing procedure. The test specimens consisted of both neat resin and glass reinforced resin. When testing glass-reinforced samples it was observed that Oxygen Index values varied inversely with resin content. Oxygen values were also obtained on specimens exposed to temperatures up to 300 C. All specimens experienced a decline in Oxygen Index when tested at an elevated temperature.

  18. A Method for Characterizing PMR-15 Resin

    NASA Technical Reports Server (NTRS)

    Roberts, G. D.; Lauver, R. W.

    1986-01-01

    Quantitative analysis technique based on reverse-phase, highperformance liquid chromatography (HPLC) and paired-ion chromatography (PIC) developed for PMR-15 resins. In reverse-phase HPLC experiment, polar solvent containing material to be analyzed passed through column packed with nonpolar substrate. Composition of PMR-15 Resin of 50 weight percent changes as resin ages at room temperature. Verification of proper resin formulation and analysis of changes in resin composition during storage important to manufacturers of PMR-15 polymer matrix composite parts. Technique especially suitable for commercial use by manufacturers of high-performance composite components.

  19. Phenoxy resins containing pendent ethynyl groups

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Jensen, B. J.; Havens, S. J.

    1984-01-01

    As part of an effort on tougher/solvent resistant matrix resins for composites, research was directed towards exploring methods to improve the solvent resistance of linear amorphous thermoplastics. Ethyl reactive groups were placed on the ends of oligomers and pendent along the polymer chain and subsequently thermally reacted to provide crosslinking and thus improvement in solvent resistance. This concept is extended to another thermoplastic, a phenoxy resin. A commercially available phenoxy resin (PKHH) was systematically modified by reaction of the pendent hydroxyl groups on the phenoxy resin with various amounts of 4-ethynylbenzoyl chloride. As the pendent ethynyl group content in the phenoxy resin increased, the cured resin exhibited a higher glass transition temperature, better solvent resistance and less flexibility. The solvent resistance was further improved by correcting a low molecular weight diethynyl compound, 2,2-bis(4-ethynylbenzoyloxy-4'-phenyl)propane, with a phenoxy resin containing pendent ethynyl groups.

  20. Foam, Foam-resin composite and method of making a foam-resin composite

    NASA Technical Reports Server (NTRS)

    Cranston, John A. (Inventor); MacArthur, Doug E. (Inventor)

    1995-01-01

    This invention relates to a foam, a foam-resin composite and a method of making foam-resin composites. The foam set forth in this invention comprises a urethane modified polyisocyanurate derived from an aromatic amino polyol and a polyether polyol. In addition to the polyisocyanurate foam, the composite of this invention further contains a resin layer, wherein the resin may be epoxy, bismaleimide, or phenolic resin. Such resins generally require cure or post-cure temperatures of at least 350.degree. F.

  1. High Temperature Transfer Molding Resins

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2000-01-01

    High temperature resins containing phenylethynyl groups that are processable by transfer molding have been prepared. These phenylethynyl containing oligomers were prepared from aromatic diamines containing phenylethynyl groups and various ratios of phthalic anhydride and 4-phenylethynlphthalic anhydride in glacial acetic acid to form a mixture of imide compounds in one step. This synthetic approach is advantageous since the products are a mixture of compounds and consequently exhibit a relatively low melting temperature. In addition, these materials exhibit low melt viscosities which are stable for several hours at 210-275 C, and since the thermal reaction of the phenylethynyl group does not occur to any appreciable extent at temperatures below 300 C, these materials have a broad processing window. Upon thermal cure at approximately 300-350 C, the phenylethynyl groups react to provide a crosslinked resin system. These new materials exhibit excellent properties and are potentially useful as adhesives, coatings, films, moldings and composite matrices.

  2. Petroleum resins and their production

    SciTech Connect

    Luvinh, Q.

    1989-04-25

    A process is described for the production of petroleum resins compatible with base polymers in hot melt formulations and having a softening point of from about 60/sup 0/C. to about 120/sup 0/C. and Gardner color of about 4 or less, comprising copolymerizing using a Friedel-Crafts catalyst. The mixture is substantially free form cyclopentadiene and dicyclopentadiene. This patent also describes a resin consisting essentially of a copolymer containing from 5 to 80 wt. % of units derived from an olefinically unsaturated aromatic compound form 5 to 80 wt. % of units derived from C/sub 5/ olefines or diolefines or C/sub 6/ olefines diolefines or a mixture of C/sub 5/ and C/sub 6/ olefines or diolefines and from 7 to 45 wt. % of units derived from a terpene.

  3. Fixation of magnet assembly to denture base using alternative resins.

    PubMed

    Okayama, Shotaro; Suzuki, Yasunori; Shimpo, Hidemasa; Ohkubo, Chikahiro

    2015-06-01

    The fixation strengths between conventional/modified magnetic assemblies and denture base resins were evaluated using six alternative resins. Magnetic assemblies with three different undercut wings were prepared. Soft lining materials with added PMMA resin polymer, two photopolymerization denture relining resins, an experimental resin, and a temporary filling resin were used to fix the magnetic assemblies to the denture bases. As a control, a commercially available magnetic assembly without undercut wings and a conventional autopolymerized resin were also prepared. After surface treatments, the magnetic assemblies were fixed using fixation resins, and tensile strengths and attractive forces were measured using an autography. The experimental resin and the temporary filling resin showed retentive forces comparable to those of conventional autopolymerized resins. Although the experimental resin demonstrated satisfactory fixation strengths, it should be necessary to improve its mechanical strength. The temporary filling resin could be used as a permanent fixation material. PMID:25904166

  4. Phosphorus-containing imide resins

    NASA Technical Reports Server (NTRS)

    Varma, I. K.; Fohlen, G. M.; Parker, J. A. (inventors)

    1984-01-01

    Flame-resistant reinforced bodies are disclosed which are composed of reinforcing fibers, filaments or fabrics in a cured body of bis- and tris-imide resins derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, or of addition polymers of such imides, including a variant in which a mono-imide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride.

  5. New modified hydrocarbon resins; An alternative to styrenated terpene resins in hot melts

    SciTech Connect

    Carper, J.D. (Hercules Inc., Wilmington, DE (US))

    1990-06-01

    This paper reports on the development of two hydrocarbon-based resin formulations that could be used with different thermoplastic block copolymers to formulate pressure-sensitive adhesives. Results are examined with one of these resins in formulations with styrene-isoprene-styrene (SIS) and styrene-butadiene (SB) compounds. The new modified hydrocarbon resin, with a softening point of 98{degrees} C, matches the adhesive performance of a terpene resin with a softening point of 105{degrees} C. The resin performs as well as the modified terpene in SIS-, SB-, and EVA-based adhesives. The new hydrocarbon resin is especially well suited for hot-melt adhesives. It exhibits low volatility, good color stability, and excellent melt viscosity stability. Since the new resin is based on petroleum hydrocarbon feedstocks, it should be available at moderate, stable prices. The other hydrocarbon resin, with a softening point of 85{degrees} C, produced comparable results.

  6. Development of tough, moisture resistant laminating resins

    NASA Technical Reports Server (NTRS)

    Brand, R. A.; Harrison, E. S.

    1982-01-01

    Tough, moisture resistant laminating resins for employment with graphite fibers were developed. The new laminating resins exhibited cost, handleability and processing characteristics equivalent to 394K (250 F) curing epoxies. The laminating resins were based on bisphenol A dicyanate and monofunctional cyanates with hydrophobic substituents. These resins sorb only small quantities of moisture at equilibrium (0.5% or less) with minimal glass transition temperature depression and represent an improvement over epoxies which sorb around 2% moisture at equilibrium. Toughening was accomplished by the precipitation of small diameter particles of butadiene nitrile rubber throughout the resin matrix. The rubber domains act as microcrack termini and energy dissipation sites, allowing increased stress accommodation prior to catastrophic failure. A unique blend of amine terminated butadiene nitrile elastomer (MW 2,000) and a high nitrile content butadiene nitrile rubber yielded the desired resin morphology.

  7. Phenolic resin and battery separator impregnated therewith

    Microsoft Academic Search

    1975-01-01

    Battery separators comprising a cellulose substrate thoroughly impregnated with an admixture of resole resin and a polyol antimigratory agent are described. The resole resin is a one-stage resin with a formaldehyde to phenol mol ratio between 1.6:1 and 2.8:1 and a molecular weight in the range of 130 to 300. After the cellulose substrate is impregnated with the admixture, it

  8. Resin selection criteria for tough composite structures

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Smith, G. T.

    1983-01-01

    Resin selection criteria are derived using a structured methodology consisting of an upward integrated mechanistic theory and its inverse (top-down structured theory). These criteria are expressed in a "criteria selection space" which are used to identify resin bulk properties for improved composite "toughness". The resin selection criteria correlate with a variety of experimental data including laminate strength, elevated temperature effects and impact resistance.

  9. Porous Ceramic Spheres from Ion Exchange Resin

    NASA Technical Reports Server (NTRS)

    Dynys, Fred

    2005-01-01

    A commercial cation ion exchange resin, cross-linked polystyrene, has been successfully used as a template to fabricate 20 to 50 micron porous ceramic spheres. Ion exchange resins have dual template capabilities. Pore architecture of the ceramic spheres can be altered by changing the template pattern. Templating can be achieved by utilizing the internal porous structure or the external surface of the resin beads. Synthesis methods and chemical/physical characteristics of the ceramic spheres will be reported.

  10. Comparison of chromatographic ion-exchange resins

    Microsoft Academic Search

    Arne Staby; Maj-Britt Sand; Ronni G. Hansen; Jan H. Jacobsen; Line A. Andersen; Michael Gerstenberg; Ulla K. Bruus; Inge Holm Jensen

    2005-01-01

    A comparative study was performed on heparin resins and strong and weak cation exchangers to investigate the pH dependence, efficiency, binding strength, particle size distribution, static and dynamic capacity, and scanning electron microscopy pictures of chromatographic resins. The resins tested include: Heparin Sepharose FF, SP Sepharose FF, CM Sepharose FF, Heparin Toyopearl 650m, SP Toyopearl 650m, CM Toyopearl 650m, Ceramic

  11. Interferometric study of epoxy resin gelation

    SciTech Connect

    Hirschbuehler, K.R.

    1981-01-01

    The transition of epoxy resins from a mobile liquid to a rubbery gel is a complex process depending on chemical reaction kinetics and both heat and mass transfer. The purpose of this study is to determine the locus of initial gelation in an epoxy resin, and the course of gelatin through both neat resins and glass fiber/epxoy resin composites. This was accomplished by monitoring the local changes in refractive index in transparent epoxy castings using laser interferometry, supplemented by temperature profiles obtained from thermocouple arrays. These experiments were carried out on pure DGEBA epoxy (DOW DER-332) cured with a variety of primary amine, secondary amine, and anhydride curing agents.

  12. Graphite composites with advanced resin matrices

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.

    1980-01-01

    The effect of processing variables on the flammability and mechanical properties for state-of-the-art and advanced resin matrices for graphite composites were studied. Resin matrices which were evaluated included state-of-the-art epoxy, phenolic-novolac, phenolic-xylok, two types of bismaleimides, benzyl, polyethersulfone, and poly(p-phenylene sulfone). Comparable flammability and thermochemical data on graphite-reinforced laminates prepared with these resin matrices are presented, and the relationship of some of these properties to the anaerobic char yield of the resins is described.

  13. Monitoring of resin flow in the resin transfer molding (RTM) process using point-voltage sensors

    Microsoft Academic Search

    Murat Danisman; Goker Tuncol; Alper Kaynar; E. Murat Sozer

    2007-01-01

    Multiple point-voltage sensors were used to monitor the mold filling stage of the resin transfer molding (RTM) process. Both lineal- and point-voltage sensors are electrical circuits in which the two poles of the sensor are closed when liquid thermoset resin arrives at the sensor location in the mold cavity. The electrical conductance of the liquid resin causes an increase in

  14. 76 FR 39896 - Granular Polytetrafluoroethylene Resin From Italy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ...Review)] Granular Polytetrafluoroethylene Resin From Italy Determination On the basis of...order on granular polytetrafluoroethylene resin from Italy would be likely to lead to continuation...entitled Granular Polytetrafluoroethylene Resin from Italy: Investigation No....

  15. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Epoxy resin containing phosphorus (generic). 721.2752 Section...721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance...generically as an epoxy resin containing phosphorus (PMN P-00-912) is subject...

  16. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Epoxy resin containing phosphorus (generic). 721.2752 Section...721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance...generically as an epoxy resin containing phosphorus (PMN P-00-912) is subject...

  17. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Epoxy resin containing phosphorus (generic). 721.2752 Section...721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance...generically as an epoxy resin containing phosphorus (PMN P-00-912) is subject...

  18. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Epoxy resin containing phosphorus (generic). 721.2752 Section...721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance...generically as an epoxy resin containing phosphorus (PMN P-00-912) is subject...

  19. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Epoxy resin containing phosphorus (generic). 721.2752 Section...721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance...generically as an epoxy resin containing phosphorus (PMN P-00-912) is subject...

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

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Acrylamide-acrylic acid resins. 176.110 Section...Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely...

  1. 21 CFR 173.10 - Modified polyacrylamide resin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...polyacrylamide resin is produced by the copolymerization of acrylamide with not more than 5-mole percent ?-methacrylyloxyethy-ltrimethylammonium...polyacrylamide resin contains not more than 0.05 percent residual acrylamide. (c) The modified polyacrylamide resin is used as...

  2. 21 CFR 173.10 - Modified polyacrylamide resin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...polyacrylamide resin is produced by the copolymerization of acrylamide with not more than 5-mole percent ?-methacrylyloxyethy-ltrimethylammonium...polyacrylamide resin contains not more than 0.05 percent residual acrylamide. (c) The modified polyacrylamide resin is used as...

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

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Acrylamide-acrylic acid resins. 176.110 Section...Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely...

  4. 21 CFR 173.10 - Modified polyacrylamide resin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...polyacrylamide resin is produced by the copolymerization of acrylamide with not more than 5-mole percent ?-methacrylyloxyethy-ltrimethylammonium...polyacrylamide resin contains not more than 0.05 percent residual acrylamide. (c) The modified polyacrylamide resin is used as...

  5. 21 CFR 173.10 - Modified polyacrylamide resin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...polyacrylamide resin is produced by the copolymerization of acrylamide with not more than 5-mole percent ?-methacrylyloxyethy-ltrimethylammonium...polyacrylamide resin contains not more than 0.05 percent residual acrylamide. (c) The modified polyacrylamide resin is used as...

  6. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Acrylamide-acrylic acid resins. 176.110 Section...Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely...

  7. Microwave-assisted preparation of functionalized resins for combinatorial synthesis

    Microsoft Academic Search

    Hao Yang; Yanqing Peng; Gonghua Song; Xuhong Qian

    2001-01-01

    A series of functionalized resins were synthesized from Merrifield resin by virtue of microwave irradiation. A significant reduction in reaction time was achieved. This method provides a rapid transformation of functionalized resin in solid-phase synthesis.

  8. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Aromatic aldehyde phenolic resin (generic). 721.5762 Section...721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical...generically as aromatic aldehyde phenolic resin (PMN P-01-573) is...

  9. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Aromatic aldehyde phenolic resin (generic). 721.5762 Section...721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical...generically as aromatic aldehyde phenolic resin (PMN P-01-573) is...

  10. 40 CFR 721.5905 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Modified phenolic resin (generic). 721.5905 Section...Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical...identified generically as a modified phenolic resin (PMN P-01-441) is...

  11. 40 CFR 721.5908 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Modified phenolic resin (generic). 721.5908 Section...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical...identified generically as modified phenolic resin (PMN P-01-561) is...

  12. 21 CFR 177.2410 - Phenolic resins in molded articles.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Phenolic resins in molded articles. 177.2410 Section...Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be...

  13. 40 CFR 721.5905 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Modified phenolic resin (generic). 721.5905 Section...Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical...identified generically as a modified phenolic resin (PMN P-01-441) is...

  14. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Aromatic aldehyde phenolic resin (generic). 721.5762 Section...721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical...generically as aromatic aldehyde phenolic resin (PMN P-01-573) is...

  15. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Aromatic aldehyde phenolic resin (generic). 721.5762 Section...721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical...generically as aromatic aldehyde phenolic resin (PMN P-01-573) is...

  16. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Aromatic aldehyde phenolic resin (generic). 721.5762 Section...721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical...generically as aromatic aldehyde phenolic resin (PMN P-01-573) is...

  17. 40 CFR 721.5905 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Modified phenolic resin (generic). 721.5905 Section...Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical...identified generically as a modified phenolic resin (PMN P-01-441) is...

  18. 21 CFR 177.2410 - Phenolic resins in molded articles.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Phenolic resins in molded articles. 177.2410 Section...Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be...

  19. 40 CFR 721.5905 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Modified phenolic resin (generic). 721.5905 Section...Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical...identified generically as a modified phenolic resin (PMN P-01-441) is...

  20. 40 CFR 721.5905 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Modified phenolic resin (generic). 721.5905 Section...Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical...identified generically as a modified phenolic resin (PMN P-01-441) is...

  1. 40 CFR 721.5908 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Modified phenolic resin (generic). 721.5908 Section...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical...identified generically as modified phenolic resin (PMN P-01-561) is...

  2. 40 CFR 721.5908 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Modified phenolic resin (generic). 721.5908 Section...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical...identified generically as modified phenolic resin (PMN P-01-561) is...

  3. 40 CFR 721.5908 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Modified phenolic resin (generic). 721.5908 Section...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical...identified generically as modified phenolic resin (PMN P-01-561) is...

  4. 21 CFR 177.2410 - Phenolic resins in molded articles.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Phenolic resins in molded articles. 177.2410 Section...Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be...

  5. 40 CFR 721.5908 - Modified phenolic resin (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Modified phenolic resin (generic). 721.5908 Section...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical...identified generically as modified phenolic resin (PMN P-01-561) is...

  6. 21 CFR 177.2510 - Polyvinylidene fluoride resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

  7. 21 CFR 177.2510 - Polyvinylidene fluoride resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2009-04-01 true Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

  8. 21 CFR 177.2510 - Polyvinylidene fluoride resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

  9. 21 CFR 177.2510 - Polyvinylidene fluoride resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

  10. 21 CFR 177.2510 - Polyvinylidene fluoride resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

  11. Quantification of Potential Arsenic Bioavailability Using Chelating Resins in Spatially Varying Geologic Environments at the Watershed Scale

    NASA Astrophysics Data System (ADS)

    Lake, G.; Herbert, B. E.; Louchouarn, P.

    2002-12-01

    Elevated concentrations of arsenic and other uranium-associated elements have been observed in surface and ground waters of the Nueces and San Antonio River watersheds, Texas. These watersheds drain the Catahoula formation which is enriched in trace elements including As, V, and U, through natural geochemical weathering over geologic time scales and intensive U mining from the 1960's to the 1980's. Mining activities have potentially impacted groundwater quality through infiltration and lateral migration of mineral-rich plumes generated by rainfall infiltration and leaching of ore bodies and spoil piles, recharge from contaminated rivers and streams, and infiltration from mine pits. The objective of this project is to quantify the potential availability of arsenic in different geologic environments at the watershed scale using chelating resins as infinite sinks. Such information has been identified as a critical need for protecting the agricultural and aquacultural resources, and the ecological quality of the Nueces Estuary system, a designated Estuary of National Significance by the U.S. Congress via the Water Quality Act of 1987. Iron-loaded resin (Dowex M4195) was exposed to spiked and equilibrated soil samples (pond sediment, river sediment, and ephemeral stream sediment) over a ninety day time period. Once removed, the resin was subjected to a 2 M NH4OH stripping procedure where the effluent was analyzed using Graphite Furnace Atomic Adsorption Spectrometry to quantify total As (average 73%\\ sorption ability and 50%\\ recovery). Additionally, the iron resins were subjected to competition studies between arsenate and phosphate and arsenate and vanadate. Preliminary results show there is little change in sorption ability as a result of the presence of the competing ion. The use of refrigeration as a means of storage showed no decreasing effect on stripping recovery of these resins over a 28 days period. Simultaneously the laboratory technique was applied to loaded resins placed in field sampling devices and exposed over a twenty-eight day period to different geologic environments (lake, river, stream, ephemeral stream, pond, and wetland). This experiment yielded a twenty-fold range in arsenic content sorbed to the resins with the wetland (2.62E-3 mmol) and river sediments (1.11E-4 mmol) representing the maximal and minimal sorption, respectively. Although these results may suggest that a higher fraction of potentially bioavailable As is present in wetland environments, stripped As concentrations will be compared to total As content in soil and water samples collected at each site to test for the influence of environmental conditions and overall concentrations on availability of this metal. Potential toxicity in different geologic environments along the watersheds is dependent on the total concentration and bioavailability of arsenic. It is important to identify those geologic environments that sequester contaminants because these systems retard contaminant transport, limit toxicity, and can act as long-term sources for the contaminant.

  12. Effect of resin rheology on macro- and micro-flows in resin transfer molding

    SciTech Connect

    Chih-Hsin Shih; Lee, L.J.; Koelling, K. [Ohio State Univ., Columbus, OH (United States)

    1996-12-31

    Resin transfer molding (RTM) is a relatively new and high potential process for near net shape composite manufacturing because of its short cycle time, low labor requirements and low equipment cost. The major material variables in the RTM process are the resin rheology and the fiber reinforcement structure. The presence of low profile additives or fillers tends to change the resin mixture from a Newtonian fluid to a Non-Newtonian fluid. Different fiber architectures may result in different flow patterns that will influence the mold filling and curing processes. This paper will discuss how the resin rheology and fiber structure effect the resin transfer molding process.

  13. Phosphorus-containing imide resins

    NASA Technical Reports Server (NTRS)

    Varma, I. K.; Fohlen, G. M.; Parker, J. A. (inventors)

    1985-01-01

    Cured polymers of bis and tris-imides derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, and addition polymers of such imides, including a variant in which a monoimide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride prior to curing are disclosed and claimed. Such polymers are flame resistant. Also disclosed are an improved method of producing tris(m-aminophenyl) phosphine oxides from the nitro analogues by reduction with hydrazine hydrate using palladized charcoal or Raney nickel as the catalyst and fiber reinforced cured resin composites.

  14. High refractive index photocurable resins

    NASA Astrophysics Data System (ADS)

    Morford, Robert V.; Mercado, Ramil L.; Planje, Curtis E.; Flaim, Tony D.

    2005-04-01

    The performance of optoelectronic devices can be increased by incorporating a high refractive index layer into the system. This paper describes several potential high refractive index resin candidates. Our materials include the added advantages over other systems because the new materials are cationically photocurable and free flowing, have low shrinkage upon cure, have no (or little) volatile organic components, are applicable by a variety of methods (dip coating, roller coating, injection molding, or film casting), can be applied in a variety of thicknesses (10-100 m), are fast-curing, and possess robust physical properties. Particular attention focuses on the refractive index in the visible spectrum, light transmission, and formulation viscosity.

  15. Polyimide Resins Resist Extreme Temperatures

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Spacecraft and aerospace engines share a common threat: high temperature. The temperatures experienced during atmospheric reentry can reach over 2,000 F, and the temperatures in rocket engines can reach well over 5,000 F. To combat the high temperatures in aerospace applications, Dr. Ruth Pater of Langley Research Center developed RP-46, a polyimide resin capable of withstanding the most brutal temperatures. The composite material can push the service temperature to the limits of organic materials. Designed as an environmentally friendly alternative to other high-temperature resins, the RP-46 polyimide resin system was awarded a 1992 "R&D 100" award, named a "2001 NASA Technology of the Year," and later, due to its success as a spinoff technology, "2004 NASA Commercial Invention of the Year." The technology s commercial success also led to its winning the Langley s "Paul F. Holloway Technology Transfer Award" as well as "Richard T. Whitcom Aerospace Technology Transfer Award" both for 2004. RP-46 is relatively inexpensive and it can be readily processed for use as an adhesive, composite, resin molding, coating, foam, or film. Its composite materials can be used in temperatures ranging from minus 150 F to 2,300 F. No other organic materials are known to be capable of such wide range and extreme high-temperature applications. In addition to answering the call for environmentally conscious high-temperature materials, RP-46 provides a slew of additional advantages: It is extremely lightweight (less than half the weight of aluminum), chemical and moisture resistant, strong, and flexible. Pater also developed a similar technology, RP-50, using many of the same methods she used with RP-46, and very similar in composition to RP-46 in terms of its thermal capacity and chemical construction, but it has different applications, as this material is a coating as opposed to a buildable composite. A NASA license for use of this material outside of the Space Agency as well as additional government-funded testing proved that RP-46 is even more exceptional than originally thought.

  16. MOLD FILLING PARAMETERS IN RESIN TRANSFER MOLDING OF COMPOSITES

    E-print Network

    MOLD FILLING PARAMETERS IN RESIN TRANSFER MOLDING OF COMPOSITES by Charles William Hedley A thesis . . . . . . . . . . . . . . . . . 9 Pultrusion . . . . . . . . . . . . . . . . . . . . 10 Resin Transfer Molding . . . . . . . . . . . . . . . . . 3 Compression Molding . . . . . . . . . . . . . . . 5 Filament Winding

  17. Characterization of a Linear Melamine Formaldehyde Resin

    Microsoft Academic Search

    Manuela Leidl; Werner F. Huber; Clemens Schwarzinger; Andreas Endesfelder

    2007-01-01

    A novel linear melamine formaldehyde resin on the basis of the bifunctional tetramethylmelamine was created. It was found to posses several promising properties for industrial applications. Structural characterization of the material at its various production states was achieved with different mass spectrometric techniques. Liquid chromatography-ion trap mass spectrometry was used to completely separate the resins and identify the individual components.

  18. Disinfection of denture base acrylic resin

    Microsoft Academic Search

    James J. Lin; Stephen M. Cameron; Dennis A. Runyan; David W. Craft

    1999-01-01

    Statement of problem. During repair or adjustments of acrylic resin removable complete and partial dentures, particles of the acrylic resin from the interior of the prosthesis may expose dental personnel to microbial health hazards if the prosthesis has not been thoroughly disinfected. Purpose. This study investigates the efficacy of a commercially prepared microbial disinfectant (Alcide) on the external and internal

  19. Fluorinated diamond bonded in fluorocarbon resin

    DOEpatents

    Taylor, Gene W. (Los Alamos, NM)

    1982-01-01

    By fluorinating diamond grit, the grit may be readily bonded into a fluorocarbon resin matrix. The matrix is formed by simple hot pressing techniques. Diamond grinding wheels may advantageously be manufactured using such a matrix. Teflon fluorocarbon resins are particularly well suited for using in forming the matrix.

  20. 21 CFR 177.1550 - Perfluorocarbon resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

  1. 21 CFR 177.1550 - Perfluorocarbon resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

  2. 21 CFR 177.1550 - Perfluorocarbon resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

  3. Silicone modified resins for graphite fiber laminates

    NASA Technical Reports Server (NTRS)

    Frost, L. W.; Bower, G. M.

    1980-01-01

    Six silicone modified resins were selected for evaluation in unidirectional filament wound graphite laminates. Neat samples of these resins had 1,000 C char residues of 6-63%. The highest flexural values measured for the laminates were a strength of 1,220 MPa and a modulus of 105 GPa. The highest interlaminar shear strength was 72 MPa.

  4. Sand control with resin and explosive

    Microsoft Academic Search

    J. M. Dees; W. J. Begnaud; N. L. Sahr

    1992-01-01

    This patent describes a method for treating a well having perforated casing to prevent solids movement through the perforations and into the wellbore. It comprises positioning a quantity of liquid resin solution such that the solution occupies the interval of the casing having perforations; positioning an explosive in proximity with the liquid resin solution; detonating the explosive; displacing the liquid

  5. A Fundamental Approach to Resin Cure Kinetics

    Microsoft Academic Search

    Leroy Chiao; Richard E. Lyon

    1990-01-01

    Thermoset polymer resins are an important class of materials, particularly when used as the matrix for advanced fiber composites. Because material performance is directly related to processing, it is useful to study the cure kinetics of these resins for use in process modeling, design and control. Several workers have attacked this problem using empirical rate laws. However, a fundamental approach

  6. Feasibility of vitrifying EPICOR II organic resins

    Microsoft Academic Search

    Buelt

    1982-01-01

    Funded by the US Department of Energy under the EG and G\\/TMI Waste Immobilization Program, Pacific Northwest Laboratory (PNL) has completed the first phase of a program in which a process designed to destroy EPICOR II resins was tested for its feasibility. These resins were utilized to remove cesium and strontium from radioactively contaminated water in the Auxiliary Building at

  7. Gold recovery with ion exchange used resins

    Microsoft Academic Search

    Carmen P. Gomes; Manuel F. Almeida; José M. Loureiro

    2001-01-01

    In this paper one strong acidic, one strong basic and one weak basic ion-exchange resins, considered as exhausted in an industrial demineralizing plant, are screened for gold recovery from cyanide solutions. Based on the observed ability for the recovery and on the ease of regeneration, the weak base anion exchanger Purolite A-100 is selected. This spent resin is stable until

  8. FLUORESCENCE EFFECTS IN ION EXCHANGE RESINS

    Microsoft Academic Search

    T. R. Flint; G. G. Eichholz

    1961-01-01

    Available as Can. Dept. Mines and Tech. Surveys, Mines Branch ; Resesrch Report R-91, 25. Fluorescence under ultraviolet illumination was ; observed in anion and cation exchange resins when in the unloaded state. The ; fluorescence decreases rapidly in intensity as the resin is loaded and this ; process is shown to offer a practical method for controlling the loading

  9. Phenolic-resin-derived activated carbons

    Microsoft Academic Search

    S. R. Tennison

    1998-01-01

    A novel binderless preparative route is described for the production of phenolic-resin-derived carbons for use as catalyst supports and adsorbents. The carbons can be produced in a wide variety of physical forms ranging from simple granules to large monolithic structures. The fully interconnected macropore structure of the carbons, which derives from the interconnected voids between the primary resin particles, can

  10. Advances in addition-cure phenolic resins

    Microsoft Academic Search

    C. P. Reghunadhan Nair

    2004-01-01

    Recent developments in the area of addition curable phenolic resins are reviewed. The article highlights the chemistry of addition-cure phenolic resins and discusses the different strategies involved in their molecular design. Structural modification through incorporation of thermally stable, addition curable groups on the novolac backbone is one strategy. The transformation of phenolic hydroxyl groups to addition curable functions forms an

  11. Hydraulic Permeability of Resorcinol-Formaldehyde Resin

    Microsoft Academic Search

    Paul Allen

    2010-01-01

    An ion exchange process using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the Hanford Site, using large scale columns as part of the Waste Treatment Plant (WTP). The RF resin is also being evaluated for use in the proposed small column ion exchange (SCIX) system,

  12. Prophylaxis with resin in wood ants

    Microsoft Academic Search

    Gregoire Castella; Michel Chapuisat; Philippe Christe

    2008-01-01

    Animals may use plant compounds to defend themselves against parasites. Wood ants, Formica paralugub- ris, incorporate pieces of solidified conifer resin into their nests. This behaviour inhibits the growth of bac- teria and fungi in nest material and protects the ants against some detrimental microorganisms. Here, we studied the resin-collecting behaviour of ants under field and laboratory conditions. First, we

  13. Continuous metal removal technique for resist resins

    NASA Astrophysics Data System (ADS)

    Wanat, Stan F.; McKenzie, Douglas S.; Rahman, M. D.

    2001-08-01

    Modern resists require very pure raw materials to insure highest quality images. Many methods have been developed to reduce metals in resins used to make photoresists. Extractive washing techniques and ion exchange methods have been the predominant methods used to reduce metal levels for these critical raw materials. This has been especially important for the novolak resins because of the generally poor quality of the starting materials used to make them and by the nature of the resin isolation steps traditionally used. Both of the commonly used cleaning methods are time consuming and are predominantly batch processes. Based upon techniques developed to efficiently fractionate resins, we have developed a technique for the rapid, continuous reduction of metal contaminants in film forming resin solutions by an extractive method using a double inlet liquid/liquid centrifuge.

  14. Chemoviscosity modeling for thermosetting resins, 2

    NASA Technical Reports Server (NTRS)

    Hou, T. H.

    1985-01-01

    A new analytical model for simulating chemoviscosity of thermosetting resin was formulated. The model is developed by modifying the Williams-Landel-Ferry (WLF) theory in polymer rheology for thermoplastic materials. By assuming a linear relationship between the glass transition temperature and the degree of cure of the resin system under cure, the WLF theory can be modified to account for the factor of reaction time. Temperature dependent functions of the modified WLF theory constants were determined from the isothermal cure data of Lee, Loos, and Springer for the Hercules 3501-6 resin system. Theoretical predictions of the model for the resin under dynamic heating cure cycles were shown to compare favorably with the experimental data reported by Carpenter. A chemoviscosity model which is capable of not only describing viscosity profiles accurately under various cure cycles, but also correlating viscosity data to the changes of physical properties associated with the structural transformations of the thermosetting resin systems during cure was established.

  15. Resin/graphite fiber composites

    NASA Technical Reports Server (NTRS)

    Cavano, P. J.

    1974-01-01

    Techniques were developed that provided thermo-oxidatively stable A-type polyimide/graphite fiber composites using the approach of in situ polymerization of monomeric reactants directly on reinforcing fibers, rather than employing separately prepared prepolymer varnish. This was accomplished by simply mixing methylene dianiline and two ester-acids and applying this solution to the fibers for subsequent molding. Five different formulated molecular weight resins were examined, and an optimized die molding procedure established for the 1500 formulated molecular weight system. Extensive ultrasonic inspection of composites was successfully utilized as a technique for monitoring laminate quality. Composite mechanical property studies were conducted with this polyimide resin at room temperature and after various time exposures in a thermo-oxidative environment at 561 K (550 F), 589 K (600 F) and 617 K (650 F). It was determined that such composites have a long term life in the temperature range of 561 K to 589 K. The final phase involved the fabrication and evaluation of a series of demonstration airfoil specimens.

  16. EPICOR-II resin degradation results from first resin samples of PF-8 and PF-20

    SciTech Connect

    McConnell, J.W. Jr.; Sanders, R.D. Sr.

    1985-12-01

    The 28 March 1979 accident at Three Mile Island Unit 2 released approximately 560,000 gallons of contaminated water to the Auxiliary and Fuel Handling Buildings. The water was decontaminated using a demineralization system called EPICOR-II developed by Epicor, Inc. The Low-Level Waste Data Base Development - EPICOR-II Resin/Liner Investigation Project is studying the chemical and physical conditions of the synthetic ion exchange resins found in several EPICOR-II prefilters. This report summarizes results and analyses of the first sampling of ion exchange resins from EPICOR-II prefilters PE-8 and -20. Results are compared with baseline data from tests performed on unirradiated Epicor, Inc. resins to determine if degradation has occurred due to the high internal radiation dose received by the EPICOR-II resins. Results also are compared with recent findings on resin degradation by Battelle Columbus Laboratories and Brookhaven National Laboratory. Analyses comparing test results of resins from EPICOR-II prefilters PF-8 and -20 with unirradiated resins obtained from Epicor, Inc. show resin degradation has occurred in some of the EPICOR-II resins examined. The mechanism of degradation is compared with work of other researchers and is consistent with their findings. The strong acid cation resins (divinylbenzene, styrene base structure) are losing effective cross-linking along with scission of functional groups and are experiencing first an increase and eventually a decrease in total exchange capacity as the absorbed radiation dose increases. The phenolic cation resins (phenol-formaldehyde base structure) show a loss of effective cross-linking and oxidation of the polymer chain. Analyses of resins removed from EPICOR-II prefilters PF-8 and -20 over the next several years should show a further increase in degradation.

  17. Tc-99 Ion Exchange Resin Testing

    SciTech Connect

    Valenta, Michelle M.; Parker, Kent E.; Pierce, Eric M.

    2010-08-01

    Pacific Northwest National Laboratory was contracted by CHPRC to evaluate the release of 99Tc from spent resin used to treat water from well 299-W15-765 and stored for several years. The key questions to be answered are: 1) does 99Tc readily release from the spent ion exchange resin after being in storage for several years; 2) if hot water stripping is used to remove the co-contaminant carbon tetrachloride, will 99Tc that has been sequestered by the resin be released; and 3) can spent resin be encapsulated into a cementitious waste form; if so, how much 99Tc would be released from the weathering of the monolith waste form? The results from the long term stability leach test results confirm that the resin is not releasing a significant amount of the sequestered 99Tc, evident by the less than 0.02% of the total 99Tc loaded being identified in the solution. Furthermore, it is possible that the measured 99Tc concentration is the result of 99Tc contained in the pore spaces of the resin. In addition to these results, analyses conducted to examine the impact of hot water on the release of 99Tc suggest that only a small percentage of the total is being released. This suggest that hot water stripping to remove carbon tetrachloride will not have a significant affect on the resin’s ability to hold-on to sequestered 99Tc. Finally, encapsulation of spent resin in a cementitious material may be a viable disposal option, but additional tests are needed to examine the extent of physical degradation caused by moisture loss and the effect this degradation process can have on the release of 99Tc.

  18. Recycling of epoxy resin compounds for moulding electronic components

    Microsoft Academic Search

    MASATOSHI Iji

    1998-01-01

    This study reports the recycling of the cured epoxy resin compounds containing silica filler and additives for moulding electronic components, which is generated as a mould residue in moulding process. The pulverized residue (moulding resin powder) showed good surface reactivity due to the functional groups contained (silanol, hydroxy and epoxy) and reacted with polar resins such as epoxy resin and

  19. Monitoring of Resin Transfer Molding Processes with Distributed Dielectric Sensors

    E-print Network

    Mamishev, Alexander

    Monitoring of Resin Transfer Molding Processes with Distributed Dielectric Sensors Michael Campbell___________________________________ #12;University of Washington Abstract Monitoring of Resin Transfer Molding Processes with Distributed-situ sensing in resin transfer molding (RTM) and vacuum-assisted resin transfer molding (VARTM) is designed

  20. Optimal control of accelerator concentration for resin transfer molding process

    Microsoft Academic Search

    Sun K. Kim; Dae-Hwan Kim; Isaac M. Daniel

    2003-01-01

    Resin cure following mold filling is an essential element in resin transfer molding. To fabricate a composite part with high dimensional stability and minimize residual stress, uniform resin cure should be achieved. This study considers a three-part resin system composed of epoxy, hardener and accelerator. The cure kinetics can be controlled by the accelerator concentration at the injection gate. A

  1. Analysis of vacuum bag resin transfer molding process

    Microsoft Academic Search

    M. K. Kang; W. I. Lee; H. T. Hahn

    2001-01-01

    An analytical model is developed to analyze the resin flow through a deformable fiber preform during vacuum bag resin transfer molding (VBRTM) process. The force balance between the resin and the fiber preform is used to account for the swelling of fiber preform inside a flexible vacuum bag. Mold filling through multiple resin inlets is analyzed under different vacuum conditions.

  2. In-depth disinfection of acrylic resins.

    PubMed

    Chau, V B; Saunders, T R; Pimsler, M; Elfring, D R

    1995-09-01

    This study demonstrated that bacteria penetrate three kinds of dental acrylic resin after a short time period. Samples of acrylic resin were contaminated with a variety of bacteria and were then placed in three different disinfecting solutions as directed by the manufacturers. After the specific dilution and immersion time, cultures were made from the resin samples. The only effective disinfectant was a 0.525% solution of sodium hypochlorite at a 10-minute immersion. It disinfected not only the surfaces but also the bacteria that penetrated the surfaces to a depth of 3 mm. PMID:7473287

  3. Resin flow/fiber deformation experiments

    SciTech Connect

    Gutowski, T.G.; Cai, Z.; Kingery, J.; Wineman, S.J.

    1986-07-01

    This paper reports on recent consolidation experiments taken on special prepregs made of aligned graphite fibers and constant viscosity oils. Three types of experiments are reported here: (1) Fiber Deformation, (2) Axial Permeability, and (3) Resin Pressure. Results show that the fibers carry a finite load at typical fiber volume fractions for advanced composites. Also, the axial permeability can be modeled by the Carman-Kozeny Theory, and Resin Flow/Fiber Deformation Theory can be used to model the resin pressure history. 5 references, 7 figures.

  4. New modified hydrocarbon resins; An alternative to styrenated terpene resins in hot melts

    Microsoft Academic Search

    Carper

    1990-01-01

    This paper reports on the development of two hydrocarbon-based resin formulations that could be used with different thermoplastic block copolymers to formulate pressure-sensitive adhesives. Results are examined with one of these resins in formulations with styrene-isoprene-styrene (SIS) and styrene-butadiene (SB) compounds. The new modified hydrocarbon resin, with a softening point of 98° C, matches the adhesive performance of a terpene

  5. Curing kinetics of phenol formaldehyde resin and wood-resin interactions in the presence of wood substrates

    Microsoft Academic Search

    Guangbo He; Bernard Riedl

    2004-01-01

    The curing kinetics of resol PF resin and resin–wood interactions in the presence of wood substrates have been studied by differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The activation energy of cure of PF resin generally increases when PF resin is mixed with wood, mainly due to the decrease of the pH values resulting from the presence

  6. Hydraulic Permeability of Resorcinol-Formaldehyde Resin

    SciTech Connect

    Taylor, Paul Allen [ORNL

    2010-01-01

    An ion exchange process using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the Hanford Site, using large scale columns as part of the Waste Treatment Plant (WTP). The RF resin is also being evaluated for use in the proposed small column ion exchange (SCIX) system, which is an alternative treatment option at Hanford and at the Savannah River Site (SRS). A recirculating test loop with a small ion exchange column was used to measure the effect of oxygen uptake and radiation exposure on the permeability of a packed bed of the RF resin. The lab-scale column was designed to be prototypic of the proposed Hanford columns at the WTP. Although the test equipment was designed to model the Hanford ion exchange columns, the data on changes in the hydraulic permeability of the resin will also be valuable for determining potential pressure drops through the proposed SCIX system. The superficial fluid velocity in the lab-scale test (3.4-5.7 cm/s) was much higher than is planned for the full-scale Hanford columns to generate the maximum pressure drop expected in those columns (9.7 psig). The frictional drag from this high velocity produced forces on the resin in the lab-scale tests that matched the design basis of the full-scale Hanford column. Any changes in the resin caused by the radiation exposure and oxygen uptake were monitored by measuring the pressure drop through the lab-scale column and the physical properties of the resin. Three hydraulic test runs were completed, the first using fresh RF resin at 25 C, the second using irradiated resin at 25 C, and the third using irradiated resin at 45 C. A Hanford AP-101 simulant solution was recirculated through a test column containing 500 mL of Na-form RF resin. Known amounts of oxygen were introduced into the primary recirculation loop by saturating measured volumes of the simulant solution with oxygen and reintroducing the oxygenated simulant into the feed tank. The dissolved oxygen (DO) concentration of the recirculating simulant was monitored, and the amount of oxygen that reacted with the resin was determined from the change in the DO concentration of the recirculating simulant solution. Prior to hydraulic testing the resin for runs 2 and 3 was covered with the simulant solution and irradiated in a spent fuel element at the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR). Both batches of resin were irradiated to a total gamma dose of 177 Mrad, but the resin for run 2 reached a maximum temperature during irradiation of 51 C, while the resin for run 3 reached a temperature of 38 C. The different temperatures were the result of the operating status of HFIR at the time of the irradiation and were not part of the test plan; however, the results clearly show the impact of the higher-temperature exposure during irradiation. The flow rate and pressure drop data from the test loop runs show that irradiating the RF resin reduces both the void fraction and the permeability of the resin bed. The mechanism for the reduction in permeability is not clear because irradiation increases the particle size of the resin beads and makes them deform less under pressure. Microscopic examination of the resin beads shows that they are all smooth regular spheres and that irradiation or oxygen uptake did not change the shape of the beads. The resin reacts rapidly with DO in the simulant solution, and the reaction with oxygen reduces the permeability of a bed of new resin by about 10% but has less impact on the permeability of irradiated resin. Irradiation increases the toughness of the resin beads, probably by initiating cross-linking reactions in them. Oxygen uptake reduces the crush strength of both new and irradiated resin; however, the pressures that caused the beads to crush are much higher than would be expected during the operation of an ion exchange column. There was no visible evidence of broken beads in any of the resin samples taken from the test loop. Reaction with oxygen red

  7. Simple and versatile operational fractionation of Fe and Zn in dietary products by solid phase extraction on ion exchange resins

    Microsoft Academic Search

    P. Pohl; B. Prusisz

    2007-01-01

    A simple and versatile protocol, based on use of solid phase extraction on strong ion exchangers and off-line detection by flame atomic absorption spectrometry, was devised to fractionate iron and zinc in common dietary food and beverages products, i.e., bee honeys, fruit juices and tea infusions. In the procedure proposed, cation exchanger Dowex 50Wx4 and anion exchanger Dowex 1x4 were

  8. Phenoxy resins containing pendent ethynyl groups and cured resins obtained therefrom

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M. (inventor)

    1985-01-01

    Phenoxy resins containing pendent ethynyl groups, the process for preparing the same, and the cured resin products obtained therefrom are disclosed. Upon the application of heat, the ethynyl groups react to provide branching and crosslinking with the cure temperature being lowered by using a catalyst if desired but not required. The cured phenoxy resins containing pendent ethynyl groups have improved solvent resistance and higher use temperature than linear uncrosslinked phenoxy resins and are applicable for use as coatings, films, adhesives, composited matrices and molding compounds.

  9. Resin Flow Analysis in the Injection Cycle of a Resin Transfer Molded Radome

    NASA Astrophysics Data System (ADS)

    Golestanian, Hossein; Poursina, Mehrdad

    2007-04-01

    Resin flow analysis in the injection cycle of an RTM process was investigated. Fiberglass and carbon fiber mats were used as reinforcements with EPON 826 epoxy resin. Numerical models were developed in ANSYS finite element software to simulate resin flow behavior into a mold of conical shape. Resin flow into the woven fiber mats is modeled as flow through porous media. The injection time for fiberglass/epoxy composite is found to be 4407 seconds. Required injection time for the carbon/epoxy composite is 27022 seconds. Higher injection time for carbon/epoxy part is due to lower permeability value of the carbon fibers compared to glass fiber mat.

  10. Improved high-temperature resistant matrix resins

    NASA Technical Reports Server (NTRS)

    Green, H. E.; Chang, G. E.; Wright, W. F.; Ueda, K.; Orell, M. K.

    1989-01-01

    A study was performed with the objective of developing matrix resins that exhibit improved thermo-oxidative stability over state-of-the-art high temperature resins for use at temperatures up to 644 K (700 F) and air pressures up to 0.7 MPa (100 psia). The work was based upon a TRW discovered family of polyimides currently licensed to and marketed by Ethyl Corporation as EYMYD(R) resins. The approach investigated to provide improved thermo-oxidative properties was to use halogenated derivatives of the diamine, 2, 2-bis (4-(4-aminophenoxy)phenyl) hexafluoropropane (4-BDAF). Polyimide neat resins and Celion(R) 12,000 composites prepared from fluorine substituted 4-BDAF demonstrated unexpectedly lower glass transition temperatures (Tg) and thermo-oxidative stabilities than the baseline 4-BDAF/PMDA polymer.

  11. Passifloricins, polyketides ?-pyrones from Passiflora foetida resin

    Microsoft Academic Search

    Fernando Echeverri; Victor Arango; Winston Quiñones; Fernando Torres; Gustavo Escobar; Yoni Rosero; Rosendo Archbold

    2001-01-01

    Three polyketides ?-pyrones, named passifloricins, were isolated from Passiflora foetida resin; their structures and relative configurations were assigned through 2D NMR spectroscopic analyses. These types of compounds were not detected in other passion flowers.

  12. Silicone modified resins for graphite fiber laminates

    NASA Technical Reports Server (NTRS)

    Frost, L. W.; Bower, G. M.

    1979-01-01

    The development of silicon modified resins for graphite fiber laminates which will prevent the dispersal of graphite fibers when the composites are burned is discussed. Eighty-five silicone modified resins were synthesized and evaluated including unsaturated polyesters, thermosetting methacrylates, epoxies, polyimides, and phenolics. Neat resins were judged in terms of Si content, homogeneity, hardness, Char formation, and thermal stability. Char formation was estimated by thermogravimetry to 1,000 C in air and in N2. Thermal stability was evaluated by isothermal weight loss measurements for 200 hrs in air at three temperatures. Four silicone modified epoxies were selected for evaluation in unidirectional filament wound graphite laminates. Neat samples of these resins had 1,000 C char residues of 25 to 50%. The highest flexural values measured for the laminates were a strength of 140 kpsi and a modulus of 10 Mpsi. The highest interlaminar shear strength was 5.3 kpsi.

  13. Synthesis of improved phenolic and polyester resins

    NASA Technical Reports Server (NTRS)

    Delano, C. B.

    1980-01-01

    Thirty-seven cured phenolic resin compositions were prepared and tested for their ability to provide improved char residues and moisture resistance over state of the art epoxy resin composite matrices. Cyanate, epoxy novolac and vinyl ester resins were investigated. Char promoter additives were found to increase the anaerobic char yield at 800 C of epoxy novolacs and vinyl esters. Moisture resistant cyanate and vinyl ester compositions were investigated as composite matrices with Thornel 300 graphite fiber. A cyanate composite matrix provided state of the art composite mechanical properties before and after humidity exposure and an anaerobic char yield of 46 percent at 800 C. The outstanding moisture resistance of the matrix was not completely realized in the composite. Vinyl ester resins showed promise as candidates for improved composite matrix systems.

  14. Radiation testing of organic ion exchange resins

    SciTech Connect

    Carlson, C.D.; Bray, L.A.; Bryan, S.A. [and others

    1995-09-01

    A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of {sup 137}Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). Samples of the exchangers were irradiated with a {sup 60}Co source to a total absorbed dose of 10{sup 9} R over a period of 5 months in a static (no flow) and a flowing configuration with neutralized current acid waste (NCAW) simulant as a feed. Based on a maximum concentration of {sup 137}Cs on the resin that would result from processing NCAW, this dose represents an operational period of at least 150 days for the RF resin and at least 1260 days for the CS-100 resin. Gas generation in the static experiment was continuously monitored and G values (molecules of gas per 100 eV) were determined for each species. Resin samples were obtained periodically and the equilibrium behavior of the resins was assessed by determining the distribution coefficients (K{sub d}s). Structural information was also obtained by {sup 13}C cross polarization magic angle (CPMAS) nuclear magnetic resonance (NMR) spectrometry and Fourier Transform Infrared (FTIR) spectroscopy so that changes to the chemical structure could be correlated with changes in K{sub d}.

  15. Comparison of chromatographic ion-exchange resins

    Microsoft Academic Search

    Arne Staby; Randi Holm Jensen; Matthias Bensch; Jürgen Hubbuch; Dorte L. Dünweber; Janus Krarup; Jacob Nielsen; Mette Lund; Steffen Kidal; Thomas Budde Hansen; Inge Holm Jensen

    2007-01-01

    A comparative study on weak anion exchangers was performed to investigate the pH dependence, binding strength, particle size distribution, and static and dynamic capacity of the chromatographic resins. The resins tested included: DEAE Sepharose FF, Poros 50 D, Fractogel EMD DEAE (M), MacroPrep DEAE Support, DEAE Ceramic HyperD 20, and Toyopearl DEAE 650 M. Testing was performed with five different

  16. Comparison of chromatographic ion-exchange resins

    Microsoft Academic Search

    Arne Staby; Inge Holm Jensen; Inger Mollerup

    2000-01-01

    A comparative study has been undertaken on various strong anion-exchangers to investigate the pH dependence, titration curves, efficiency, binding strength, and dynamic capacity of the chromatographic resins. The resins tested included: Macro-Prep 25Q, TSK-Gel Q-5PW-HR, Poros QE\\/M, Q Sepharose FF, Q HyperD 20, Q Zirconia, Source 30Q, Fractogel EMD TMAE 650s, and Express-Ion Q. Testing was performed with five different

  17. Comparison of chromatographic ion-exchange resins

    Microsoft Academic Search

    Arne Staby; Inge Holm Jensen

    2001-01-01

    A comparative study was performed on strong anion exchangers to investigate the pH dependence, titration curves, efficiency, binding strength, particle size distribution, and static and dynamic capacity of the chromatographic resins. The resins tested included Q Sepharose XL, UNO Q-1, Poros 50 HQ, Toyopearl QAE 550c, Separon HemaBio 1000Q, Q-Cellthru Bigbeads Plus, Q Sepharose HP and Toyopearl SuperQ 650s. Testing

  18. Studies on Cesium Uptake by Phenolic Resins

    Microsoft Academic Search

    S. K. Samanta; M. Ramaswamy; B. M. Misra

    1992-01-01

    The selective removal of cesium by phenolic ion-exchange resins from highly salted alkaline radioactive solutions was studied. The resins were synthesized by alkaline polycondensation of phenol, resorcinol, catechol, and a resorcinol-catechol mixture with formaldehyde and characterized for their moisture regain, ion-exchange (H?Na) capacity, and distribution coefficient (KD) for cesium. The effects of open and sealed curing of the polymers on

  19. Cleanup of TMI-2 demineralizer resins

    SciTech Connect

    Bond, W.D.; King, L.J.; Knauer, J.B.; Hofstetter, K.J.; Thompson, J.D.

    1985-01-01

    Radiocesium is being removed from Demineralizers A and B (DA and DB by a process that was developed from laboratory tests on small samples of resin from the demineralizers. The process was designed to elute the radiocesium from the demineralizer resins and then to resorb it onto the zeolite ion exchangers contained in the Submerged Demineralizer System (SDS). The process was also required to limit the maximum cesium activities in the resin eluates (SDS feeds) so that the radiation field surrounding the pipelines would not be excessive. The process consists of 17 stages of batch elution. In the initial stage, the resin is contacted with 0.18 M boric acid. Subsequent stages subject the resin to increasing concentrations of sodium in NaH/sub 2/BO/sub 3/-H/sub 3/BO/sub 3/ solution (total B = 0.35 M) and then 1 M sodium hydroxide in the final stages. Results on the performance of the process in the cleanup of the demineralizers at TMI-2 are compared to those obtained from laboratory tests with small samples of the DA and DB resins. To date, 15 stages of batch elution have been completed on the demineralizers at TMI-2 which resulted in the removal of about 750 Ci of radiocesium from DA and about 3300 Ci from DB.

  20. Ion Exchange Temperature Testing with SRF Resin

    SciTech Connect

    Russell, Renee L.; Rinehart, Donald E.; Brown, Garrett N.; Peterson, Reid A.

    2012-03-01

    Ion exchange using the Spherical Resorcinol-Formaldehyde (SRF) resin has been selected by the U.S. Department of Energy’s Office of River Protection for use in the Pretreatment Facility of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) and for potential application in an at-tank deployment for removing 137Cs. Recent proposed changes to the WTP ion exchange process baseline indicate that higher temperatures (50°C) to alleviate post-filtration precipitation issues prior to reaching the ion exchange columns may be required. Therefore, it is important to understand the behavior of SRF resin performance under the conditions expected with the new equipment and process changes. This research examined the impact of elevated temperature on resin loading and resin degradation during extended solution flow using elevated temperature (45°, 50°, 55°, 60°, 65°, 75°C). Testing for extended times at elevated temperatures showed that the resin does degrade and loading capacity is reduced at and above 45°C. Above 60°C the resin appears to not load at all.

  1. Epoxy resin system for in situ rehabilitation of pipes

    SciTech Connect

    Edwards, G.D.; Wilson, B.S.

    1992-04-14

    This patent describes a process for in situ pipe rehabilitation. It comprises: impregnating a fibrous substrate with a liquid epoxy resin composition comprising at least one liquid epoxy resin having epoxide equivalent weight within the range of about 165 to about 195; a minor amount, relative to the liquid epoxy resin, of an epoxide functional reactive diluent; a minor amount, relative to the liquid epoxy resin, of a thixotroping agent; and an effective amount of a liquid curing agent comprising a polyamide resin, a polyoxalkylenediamine, and from about 35 to about 55 weight percent, based on the weight of component, of 2-ethyl-4-methyl imidazole or derivatives thereof; positioning the resin-impregnated fibrous substrate within a pipe to be rehabilitated so that a surface of the resin-impregnated fibrous substrate is in contact with the interior surface of the pipe; and subjecting the thus-positioned resin-impregnated fibrous substrate to conditions effective to cure the liquid epoxy resin.

  2. Bonding of resin core materials to lithium disilicate ceramics: the effect of resin cement film thickness.

    PubMed

    Cekic-Nagas, Isil; Canay, Senay; Sahin, Erdal

    2010-01-01

    The aim of this study was to investigate the effect of different resin cement film thicknesses on the shear bond strength of resin core materials to lithium disilicate ceramics. Forty IPS Empress 2 ceramic disks were bonded to the core materials (Bis-core and Smile) with resin cement film thicknesses of 50 or 100 ?m. Shear bond strength was measured using a universal testing machine. Data were analyzed using two-way analysis of variance and independent t tests. The core material used and resin cement film thickness had a significant effect on shear bond strength values (P < .001). Greater resin cement film thickness resulted in decreased bond strength of the core materials to lithium disilicate ceramics. PMID:20859565

  3. Antibacterial properties of dentin bonding systems, polyacid-modified composite resins and composite resins.

    PubMed

    Karanika-Kouma, A; Dionysopoulos, P; Koliniotou-Koubia, E; Kolokotronis, A

    2001-02-01

    This study examined the antibacterial activities of the bonding systems Syntac, EBS and Scotchbond 1, the polyacid-modified composite resins Hytac and Compoglass, and the composite resins Tetric, Z100 and Scalp-it. They were evaluated using the cariogenic bacteria Streptococcus mutans, Lactobacillus salivarius, Streptococcus sorbinus and Actinomyces viscosus in vitro with a modified cylinder drop plate agar diffusion assay. All adhesives of the dentin bonding systems and the polyacid-modified composite resins exhibited various degrees of antibacterial activity against all of the test bacteria. On the contrary, composite resins did not affect bacterial growth. The data suggest that the use of these adhesives and polyacid-modified composite resins may reduce the consequences of microleakage owing to their antibacterial properties. PMID:11298264

  4. New bismaleimide matrix resins for graphite fiber composites

    NASA Technical Reports Server (NTRS)

    Hsu, M.-T. S.; Chen, T. S.; Parker, J. A.; Heimbuch, A. H.

    1985-01-01

    Two new bismaleimide resins based on the N,N'-m-phenylene-bis(m-amino-benzamide) structure have been synthesized and characterized. The mixtures of the two resins gave better handling, processing, mechanical, and thermal properties in graphite composites than did the individual resins. The mechanical strength of the cured graphite composites prepared from the 1:1 copolymer of the two bismaleimide resins was excellent at both ambient and elevated temperatures. The physical and mechanical properties of the composites from the new bismaleimide matrix resin systems are compared with conventional composites based on epoxy and other bismaleimide systems. The copolymer system provides another method for improving bismaleimide resins.

  5. New bismaleimide matrix resins for graphite fiber composites

    NASA Technical Reports Server (NTRS)

    Hsu, M.-T. S.; Chen, T. S.; Parker, J. A.; Heimbuch, A. H.

    1985-01-01

    Two new bismaleimide resins based on the N, N'-m-phenylene-bis(m-amino-benzamide) structure have been synthesized and characterized. The mixtures of the two resins gave better handling, processing, mechanical, and thermal properties in graphite composites than did the individual resins. The mechanical strength of the cured graphite composites prepared from the 1:1 copolymer of the two bismaleimide resins was excellent at both ambient and elevated temperatures. The physical and mechanical properties of the composites from the new bismaleimide matrix resin systems are compared with conventional composites based on epoxy and other bismaleimide systems. The copolymer system provides another method for improving bismaleimide resins.

  6. Resin flow monitoring in vacuum-assisted resin transfer molding using optical fiber distributed sensor

    NASA Astrophysics Data System (ADS)

    Eum, Soohyun; Kageyama, Kazuro; Murayama, Hideaki; Ohsawa, Isamu; Uzawa, Kiyoshi; Kanai, Makoto; Igawa, Hirotaka

    2007-04-01

    In this study, we implemented resin flow monitoring by using an optical fiber sensor during vacuum assisted resin transfer molding (VaRTM).We employed optical frequency domain reflectometry (OFDR) and fiber Bragg grating (FBG) sensor for distributed sensing. Especially, long gauge FBGs (about 100mm) which are 10 times longer than an ordinary FBG were employed for more effective distributed sensing. A long gauge FBG was embedded in GFRP laminates, and other two ones were located out of laminate for wavelength reference and temperature compensation, respectively. During VaRTM, the embedded FBG could measure how the preform affected the sensor with vacuum pressure and resin was flowed into the preform. In this study, we intended to detect the gradient of compressive strain between impregnated part and umimpregnated one within long gauge FBG. If resin is infused to preform, compressive strain which is generated on FBG is released by volume of resin. We could get the wavelength shift due to the change of compressive strain along gauge length of FBG by using short-time Fourier transformation for signal acquired from FBG. Therefore, we could know the resin flow front with the gradient of compressive strain of FBG. In this study, we used silicon oil which has same viscosity with resin substitute for resin in order to reuse FBG. In order to monitor resin flow, the silicon oil was infused from one edge of preform, the silicon oil was flowed from right to left. Then, we made dry spot within gauge length by infusing silicon oil to both sides of preform to prove the ability of dry spot monitoring with FBG. We could monitor resin flow condition and dry spot formation successfully using by FBG based on OFDR.

  7. 50W CW output power and 12mJ pulses from a quasi-2-level Yb:YAG ceramic rod laser end-pumped at the 969nm zero-phonon line

    NASA Astrophysics Data System (ADS)

    Fries, Christian; Weitz, Marco; Theobald, Christian; v. Löwis of Menar, Patric; Bartschke, Jürgen; L'huillier, Johannes A.

    2015-02-01

    With the advent of high power and narrow bandwidth 969 nm pump diodes, direct pumping into the upper laser level of Yb:YAG and hence quasi-2-level lasers became possible. Pumping directly into the emitting level leads to higher quantum efficiency and reduction of non-radiative decay. Consequently, thermal load, thermal lensing and risk of fracture are reduced significantly. Moreover pump saturation and thermal population of uninvolved energy-levels in ground and excited states are benefical for a homogenous distribution of the pump beam as well as the reduction of reabsorption loss compared to 3-level systems, which allows for high-power DPSS lasers. Beside continuous-wave (cw) operation, nanosecond pulses with a repetition rate between 1 and 5 kHz are an attractive alternative to flashlamp-pumped systems (10-100 Hz) in various measurement applications that require higher data acquisition rates because of new faster detectors. Based on measurements of the absorption and a detailed numerical model for pump beam distribution, including beam propagation and saturation factors, power-scaling of a ceramic rod Yb:YAG oscillator was possible. Finally a cw output power of 50 W with 33 % pump efficiency at 1030 nm has been demonstrated (M2 < 1.2). Nanosecond pulses have been produced by cavity-dumping of this system. The cavity-dumped setup allowed for 3-10 ns pulses with a pulse energy of 12.5 mJ at 1 kHz (M2 < 1.1). In order to achieve these results a systematic experimental and numerical investigation on gain dynamics and the identification of different stable operating regimes has been carried out.

  8. 76 FR 42114 - Granular Polytetrafluoroethylene Resin From Italy: Continuation of Antidumping Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-18

    ...Granular Polytetrafluoroethylene Resin From Italy: Continuation of Antidumping Duty Order...polytetrafluoroethylene resin (``PTFE resin'') from Italy would likely lead to a continuation or...antidumping duty order on PTFE resin from Italy, pursuant to section 751(c)(2)...

  9. 76 FR 12939 - Granular Polytetrafluoroethylene Resin From Italy: Final Results of Expedited Sunset Review of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-09

    ...Granular Polytetrafluoroethylene Resin From Italy: Final Results of Expedited Sunset Review...polytetrafluoroethylene resin (``PTFE resin'') from Italy. The Department has conducted an expedited...antidumping duty order on PTFE resin from Italy pursuant to section 751(c) of the...

  10. Diffusion of residual monomer in polymer resins.

    PubMed Central

    Piver, W T

    1976-01-01

    A simplified mathematical model which made use of Fick's laws of diffusion written in spherical coordinates was developed to describe the rate of diffusion of residual monomers from polymer resins. The properties of the monomer-polymer system which influenced the amount of monomer remaining in the polymer as a function of time were the diffusivity and solubility of the monomer in the polymer, and the particle size of the polymer resin. This model was used to analyze literature data on the diffusion of residual vinyl chloride monomer in polyvinyl chloride resins made by the suspension process. It was concluded that particle size of the resin was a significant parameter which should be taken advantage of in process equipment designed to remove residual monomer from PVC resins. The diffusivity of the monomer in the polymer was a function of the solubility of the monomer in the polymer. Monomer solubility can be determined from Henry's law. It was suggested that this model could be adapted to describe diffusion of monomers from any monomer-polymer system, and would be a useful approach to modeling the transport of nonreactive chemical additives from plastics. PMID:1026410

  11. Development of a heterogeneous laminating resin system

    NASA Technical Reports Server (NTRS)

    Biermann, T. F.; Hopper, L. C.

    1985-01-01

    The factors which effect the impact resistance of laminating resin systems and yet retain equivalent performance with the conventional 450 K curing epoxy matrix systems in other areas were studied. Formulation work was conducted on two systems, an all-epoxy and an epoxy/bismaleimide, to gain fundamental information on the effect formulation changes have upon neat resin and composite properties. The all-epoxy work involved formulations with various amounts and combinations of eight different epoxy resins, four different hardeners, fifteen different toughening agents, a filler, and a catalyst. The epoxy/bismaleimide effort improved formulations with various amounts and combinations of nine different resins, four different hardeners, eight different toughening agents, four different catalysts, and a filler. When a formulation appeared to offer the proper combination of properties required for a laminating resin Celion 3K-70P fabric was prepregged. Initial screening tests on composites primarily involved Gardner type impact and measurement of short beam shear strengths under dry and hot/wet conditions.

  12. FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES

    E-print Network

    FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.................................................................................................8 Resin Systems

  13. Improved resin infiltration of natural caries lesions.

    PubMed

    Meyer-Lueckel, H; Paris, S

    2008-12-01

    In artificial lesions, improved penetration and the caries-inhibiting properties of infiltrating resins could be observed with increasing penetration coefficients (PCs). The aim of the present study was to compare the penetration abilities of an experimental 'infiltrant' into natural lesions with those of an adhesive in vitro. Extracted human molars and premolars showing proximal white spots were cut across the lesions perpendicular to the surface. Corresponding lesion halves were etched for 120 sec with 15% hydrochloric acid gel and were subsequently treated with either an adhesive (PC: 31 cm/sec) or an infiltrant (PC: 273 cm/sec). Specimens were observed by confocal microscopy and transverse microradiography. Penetration depths of the adhesive were significantly lower compared with those of the infiltrant (p < 0.001; Wilcoxon). It can be concluded that resins with higher PCs (infiltrants) show superior ability to penetrate natural lesions compared with resins with lower PCs. PMID:19029077

  14. Novel strontium-selective extraction chromatographic resin

    SciTech Connect

    Horwitz, E.P.; Chiarizia, R.; Dietz, M.L. [Argonne National Lab., IL (United States)

    1992-04-01

    The effect of nitric acid concentration on the selectivity of a novel extraction chromatographic resin consisting of an octanol solution of 4,4`(5`)-bis(t-butyl-cyclohexano)-18-crown-6 sorbed on an inert polymeric support for strontium over a number of alkali, alkaline earth, and other metal cations was evaluated. The effect of macro quantities of selected elements on strontium retention by the resin was also examined. The resin is shown to exhibit excellent selectivity for strontium over nearly all of the test elements; only lead and tetravalent neptunium, polonium, and plutonium show significant affinity for the material. In addition, concentrations of calcium or sodium ion up to approx.0.1 M are shown not to diminish the sorption of strontium appreciably. Several useful radiochemical separation schemes devised on the basis of the results obtained are described. 35 refs., 6 figs., 3 tabs.

  15. The Creep of Laminated Synthetic Resin Plastics

    NASA Technical Reports Server (NTRS)

    Perkuhn, H

    1941-01-01

    The long-time loading strength of a number of laminated synthetic resin plastics was ascertained and the effect of molding pressure and resin content determined. The best value was observed with a 30 to 40 percent resin content. The long-time loading strength also increases with increasing molding pressure up to 250 kg/cm(exp 2); a further rise in pressure affords no further substantial improvement. The creep strength is defined as the load which in the hundredth hour of loading produces a rate of elongation of 5 X 10(exp -4) percent per hour. The creep strength values of different materials were determined and tabulated. The effect of humidity during long-term tests is pointed out.

  16. Studies on cesium uptake by phenolic resins

    SciTech Connect

    Samanta, S.K.; Ramaswamy, M.; Misra, B.M. (Bhabha Atomic Research Centre, Bombay (India))

    1992-02-01

    The selective removal of cesium by phenolic ion-exchange resins from highly salted alkaline radioactive solutions was studied. The resins were synthesized by alkaline polycondensation of phenol, resorcinol, catechol, and resorcinol-catechol mixture with formaldehyde and characterized for their moisture regain, ion-exchange (H{sup +} {yields} Na{sup +}) capacity, and distribution coefficient (K{sub D}) for cesium. The effects of open and sealed curing of the polymers on their properties were studied. The effect of Na{sup +}, NaOH, and Cs{sup +} concentration on the uptake of cesium by resorcinol-formaldehyde resin was investigated, in particular. The chemical, thermal, and radiation stabilities of the polymers were also studied.

  17. Standard tests for toughened resin composites, revised edition

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Several toughened resin systems are evaluated to achieve commonality for certain kinds of tests used to characterize toughened resin composites. Specifications for five tests were standardized; these test standards are described.

  18. Reactivity of Trametes laccases with fatty and resin acids.

    PubMed

    Karlsson, S; Holmbom, B; Spetz, P; Mustranta, A; Buchert, J

    2001-04-01

    Lipophilic extractives commonly referred to as wood pitch or wood resin can have a negative impact on paper machine runnability and product quality. The lipophilic extractives are composed mainly of fatty acids, resin acids, sterols, steryl esters and triglycerides. In this work, the suitability of laccases for the modification of fatty and resin acids was studied, using two model fractions. In the treatments, resin and fatty acid dispersions were treated with two different laccases, i.e. laccases from Trametes hirsuta and T. villosa. Different chromatographic methods were used to elucidate the effects of laccase treatments on the chemistry of the fatty and resin acids. Both laccases were able to modify the fatty and resin acids to some extent. In the case of fatty acids, a decrease in the amount of linoleic, oleic and pinolenic acids was observed, whereas the modification of resin acids resulted in a reduced amount of conjugated resin acids. PMID:11341313

  19. 76 FR 8774 - Granular Polytetrafluoroethylene Resin From Japan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ...731-TA-386 (Third Review)] Granular Polytetrafluoroethylene Resin From Japan AGENCY: United States International Trade Commission...the antidumping duty order on granular polytetrafluoroethylene resin from Japan would be likely to lead to continuation or...

  20. Taste masking of Etoricoxib by using ion-exchange resin.

    PubMed

    Patra, Sradhanjali; Samantaray, Rakesh; Pattnaik, Saswat; Barik, B B

    2010-01-01

    The present study was carried out in order to mask the bitter taste of the Etoricoxib by complexation with cation-exchange resin, Indion 204. The drug resin complexes (DRC) were prepared by batch process and efficient drug loading was obtained by using inactivated form of resin in the drug-resin ratio 1:3.3 with 30 min swelling time of resin in 25 mL of water with 5 min stirring time. Drug-resin complexes were characterized for dissolution studies and spectral studies. Drug release from drug-resin complex in salivary pH was insufficient to impart bitter taste. Volunteers rated the drug resin complex as tasteless and agreeable. PMID:19845450

  1. Resin additive improves performance of high-temperature hydrocarbon lubricants

    NASA Technical Reports Server (NTRS)

    Johnson, R. L.; Loomis, W. R.

    1971-01-01

    Paraffinic resins, in high temperature applications, improve strength of thin lubricant film in Hertzian contacts even though they do not increase bulk oil viscosity. Use of resin circumvents corrosivity and high volatility problems inherent with many chemical additives.

  2. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...of the calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by weight of titanium dioxide as an optional adjuvant substance. (c) The mineral reinforced nylon resins with or without the optional...

  3. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

  4. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

  5. Influence of resin coating materials on Porphyromonas gingivalis attachment.

    PubMed

    Kumada, Ai; Matsuka, Yoshizo; Mine, Atsushi; Ono, Mitsuaki; Uehara, Junji; Sonoi, Norihiro; Ito, Takashi; Takashiba, Shogo; Kuboki, Takuo

    2012-02-01

    Resin coating materials have been used for composite resin or provisional restoration in order to prevent plaque accumulation on their surfaces. However, it is not clear whether the coating materials influence attachment of periodontal bacteria. Therefore, we investigated the effect of resin coating materials on the attachment of Porphyromonas gingivalis (Pg). The polymerized auto cure resin plates were coated with two resin coating materials. To estimate the Pg attachment, each plate was immersed in brain heart infusion medium containing Pg. The quantity of bacteria attached on each plate was evaluated by crystal violet quantification. Morphological change of Pg was recorded using scanning electron microscopy. Both coating groups presented significantly lower Pg attachment compared to the control. The Pg shapes on the plates with resin coating materials were similar to the non-treated control plates. The resin coating materials clearly prevent Pg attachment on the polymerized auto cure resin plate. PMID:22277610

  6. Performance Properties of Graphite Reinforced Composites with Advanced Resin Matrices

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.

    1980-01-01

    This article looks at the effect of different resin matrices on thermal and mechanical properties of graphite composites, and relates the thermal and flammability properties to the anaerobic char yield of the resins. The processing parameters of graphite composites utilizing graphite fabric and epoxy or other advanced resins as matrices are presented. Thermoset resin matrices studied were: aminecured polyfunctional glycidyl aminetype epoxy (baseline), phenolicnovolac resin based on condensation of dihydroxymethyl-xylene and phenol cured with hexamine, two types of polydismaleimide resins, phenolic resin, and benzyl resin. The thermoplastic matrices studied were polyethersulfone and polyphenylenesulfone. Properties evaluated in the study included anaerobic char yield, limiting oxygen index, smoke evolution, moisture absorption, and mechanical properties at elevated temperatures including tensile, compressive, and short-beam shear strengths. Generally, it was determined that graphite composites with the highest char yield exhibited optimum fire-resistant properties.

  7. Biphenyl liquid crystalline epoxy resin as a low-shrinkage resin-based dental restorative nanocomposite.

    PubMed

    Hsu, Sheng-Hao; Chen, Rung-Shu; Chang, Yuan-Ling; Chen, Min-Huey; Cheng, Kuo-Chung; Su, Wei-Fang

    2012-11-01

    Low-shrinkage resin-based photocurable liquid crystalline epoxy nanocomposite has been investigated with regard to its application as a dental restoration material. The nanocomposite consists of an organic matrix and an inorganic reinforcing filler. The organic matrix is made of liquid crystalline biphenyl epoxy resin (BP), an epoxy resin consisting of cyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ECH), the photoinitiator 4-octylphenyl phenyliodonium hexafluoroantimonate and the photosensitizer champhorquinone. The inorganic filler is silica nanoparticles (?70-100 nm). The nanoparticles were modified by an epoxy silane of ?-glycidoxypropyltrimethoxysilane to be compatible with the organic matrix and to chemically bond with the organic matrix after photo curing. By incorporating the BP liquid crystalline (LC) epoxy resin into conventional ECH epoxy resin, the nanocomposite has improved hardness, flexural modulus, water absorption and coefficient of thermal expansion. Although the incorporation of silica filler may dilute the reinforcing effect of crystalline BP, a high silica filler content (?42 vol.%) was found to increase the physical and chemical properties of the nanocomposite due to the formation of unique microstructures. The microstructure of nanoparticle embedded layers was observed in the nanocomposite using scanning and transmission electron microscopy. This unique microstructure indicates that the crystalline BP and nanoparticles support each other and result in outstanding mechanical properties. The crystalline BP in the LC epoxy resin-based nanocomposite was partially melted during exothermic photopolymerization, and the resin expanded via an order-to-disorder transition. Thus, the post-gelation shrinkage of the LC epoxy resin-based nanocomposite is greatly reduced, ?50.6% less than in commercialized methacrylate resin-based composites. This LC epoxy nanocomposite demonstrates good physical and chemical properties and good biocompatibility, comparable to commercialized composites. The results indicate that this novel LC nanocomposite is worthy of development and has potential for further applications in clinical dentistry. PMID:22842038

  8. Resin-bonded retainers. Part I: Resin bond to electrolytically etched nonprecious alloys.

    PubMed

    Thompson, V P; Del Castillo, E; Livaditis, G J

    1983-12-01

    Nonprecious Ni-Cr casting alloys can be electrolytically etched to yield a highly retentive surface for micromechanical bonding of dental resins. The acid, current density, and etching time to achieve the retentive features are specific for each alloy. Conditions for etching one beryllium-containing and one non-beryllium-containing alloy are described. The tensile strength of a resin system to these alloys has been determined to be over two times the accepted value of the resin bond to acid-etched enamel. PMID:6361240

  9. Technical assessment for quality control of resins

    NASA Technical Reports Server (NTRS)

    Gosnell, R. B.

    1977-01-01

    Survey visits to companies involved in the manufacture and use of graphite-epoxy prepregs were conducted to assess the factors which may contribute to variability in the mechanical properties of graphite-epoxy composites. In particular, the purpose was to assess the contributions of the epoxy resins to variability. Companies represented three segments of the composites industry - aircraft manufacturers, prepreg manufacturers, and epoxy resin manufacturers. Several important sources of performance variability were identified from among the complete spectrum of potential sources which ranged from raw materials to composite test data interpretation.

  10. New phosphorus-containing bisimide resins

    NASA Technical Reports Server (NTRS)

    Varma, I. K.; Fohlen, G. M.; Hsu, M.-T.; Parker, J. A.

    1984-01-01

    Phosphorus-based flame retardants have been effectively used in a wide variety of polymeric materials. Such additives, however, may either influence the decomposition reaction in polymers or lack durability due to a tendency to be leached out by solvents. Attention is given to the synthesis, characterization, thermal stability and degradation mechanisms of bisimide resins, and an evaluation is conducted of the flammability and mechanical properties of graphite cloth-reinforced laminates fabricated from one of the six phosphorus-containing bisimide resins considered.

  11. Differential Curing In Fiber/Resin Laminates

    NASA Technical Reports Server (NTRS)

    Webster, Charles N.

    1989-01-01

    Modified layup schedule counteracts tendency toward delamination. Improved manufacturing process resembles conventional process, except prepregs partially cured laid on mold in sequence in degree of partial cure decreases from mold side to bag side. Degree of partial cure of each layer at time of layup selected by controlling storage and partial-curing temperatures of prepreg according to Arrhenius equation for rate of gel of resin as function of temperature and time from moment of mixing. Differential advancement of cure in layers made large enough to offset effect of advance bag-side heating in oven or autoclave. Technique helps prevent entrapment of volatile materials during manufacturing of fiber/resin laminates.

  12. Benzonorbornadiene end caps for PMR resins

    NASA Technical Reports Server (NTRS)

    Panigot, Michael J.; Waters, John F.; Varde, Uday; Sutter, James K.; Sukenik, Chaim N.

    1992-01-01

    Several ortho-disubstituted benzonorbornadiene derivatives are described. These molecules contain acid, ester, or anhydride functionality permitting their use as end caps in PMR (polymerization of monomer reactants) polyimide systems. The replacement of the currently used norbornenyl end caps with benzonorbornadienyl end caps affords resins of increased aromatic content. It also allows evaluation of some mechanistic aspects of PMR cross-linking. Initial testing of N-phenylimide model compounds and of actual resin formulations using the benzonorbornadienyl end cap reveals that they undergo efficient thermal crosslinking to give oligomers with physical properties and thermal stability comparable to commercial norbornene-end-capped PMR systems.

  13. Radiographic detection of overhangs formed by resin composite luting agents

    Microsoft Academic Search

    B. O'Rourke; A. W. G. Walls; R. W. Wassell

    1995-01-01

    Objectives: An in vitro model was used to assess the ability of standard radiographic techniques to detect marginal overhangs of resin composite luting agents beside porcelain and resin composite inlays.Methods: The radiodensity of five commercially available luting resins was determined using ISO 4049 methodology. For four of the luting agents, artificial overhangs (0.5 × 0.5 × 2 mm) were created

  14. Shear and tensile bond testing for resin cement evaluation

    Microsoft Academic Search

    Yuichi Kitasako; Michael F. Burrow; Toru Nikaido; Naoko Harada; Shigehisa Inokoshi; Toshimoto Yamada; Toshio Takatsu

    1995-01-01

    Objectives. The aim of this study was to compare the tensile and shear bond strengths of one experimental and four commercially available resin cements following the ISO document TR 110405 for bond measurement.Methods. Tensile and shear bond tests were performed using bovine enamel and dentin as the tooth substrate with each of the resin cements. Resin composite rods were cemented

  15. ELUTION OF URANIUM VALUES FROM ION EXCHANGE RESINS

    Microsoft Academic Search

    1959-01-01

    A process is described for eluting complex uranium ions absorbed on ion ; exchange resins. The resin is subjected to the action of an aqueous eluting ; solution contuining sulfuric acid and an alkali metal, ammonium, or magnesium ; chloride or nitrate, the elution being carried out until the desired amount of ; the uranium is removed from the resin.

  16. Evaluation of Leachable Behavior from Ion Exchange Resins

    Microsoft Academic Search

    Hiroo IGARASHI; Yusaku NISHIMURA; Katsumi OHSUMI; Shunsuke UCHIDA; Tsuneo MATSUI

    1999-01-01

    The elution rate of leachables from ion exchange resin, which is used in condensate demineralizers and is one of several major sources of organic compounds in BWR cooling water, was measured. Properties of the leachables and elution rate depended on the kind of ion exchange resin and the years of use. The organic compounds elution rate of cation exchange resin

  17. Epoxy resin system for in situ rehabilitation of pipes

    Microsoft Academic Search

    G. D. Edwards; B. S. Wilson

    1992-01-01

    This patent describes a process for in situ pipe rehabilitation. It comprises: impregnating a fibrous substrate with a liquid epoxy resin composition comprising at least one liquid epoxy resin having epoxide equivalent weight within the range of about 165 to about 195; a minor amount, relative to the liquid epoxy resin, of an epoxide functional reactive diluent; a minor amount,

  18. Modification of epoxy resin using reactive liquid (ATBN) rubber

    Microsoft Academic Search

    N Chikhi; S Fellahi; M Bakar

    2002-01-01

    Epoxy resins are widely utilised as high performance thermosetting resins for many industrial applications but unfortunately some are characterised by a relatively low toughness. In this respect, many efforts have been made to improve the toughness of cured epoxy resins by the introduction of rigid particles, reactive rubbers, interpenetrating polymer networks and engineering thermoplastics within the matrix.In the present work

  19. ACC Resin Statistics Annual Summary PRODUCTION, SALES & CAPTIVE USE

    E-print Network

    Laughlin, Robert B.

    .1 (1) Except Phenolic resins, which are reported on a gross weight basis. (2) Sales & Captive Use dataACC Resin Statistics Annual Summary PRODUCTION, SALES & CAPTIVE USE (millions of pounds, dry weight basis)(1) Production Total Sales & Captive Use Resin % Chg % Chg 2008 2007 08/07 2008 2007 08/07 Epoxy

  20. Engineering Plastics from Lignin. IX. Phenolic Resin Synthesis and Characterization

    Microsoft Academic Search

    Peter C. Muller; Stephen S. Kelley; Wolfgang G. Glasser

    1984-01-01

    The performance of phenol-formaldehyde (PF) resins, formulated with lignin derivatives previously synthesized as phenolic resin prepolymers, was evaluated by thermal analysis of the curing process, and by a hard maple shear block test. At 54 and 60% phenol replacement levels, respectively, kraft (KL) and steam explosion lignin (SEL)-based resoles exhibited cure behavior very similar to a standard PF resin. Acid

  1. Reusable chelating resins concentrate metal ions from highly dilute solutions

    NASA Technical Reports Server (NTRS)

    Bauman, A. J.; Weetal, H. H.; Weliky, N.

    1966-01-01

    Column chromatographic method uses new metal chelating resins for recovering heavy-metal ions from highly dilute solutions. The absorbed heavy-metal cations may be removed from the chelating resins by acid or base washes. The resins are reusable after the washes are completed.

  2. Photosensitive filler minimizes internal stresses in epoxy resins

    NASA Technical Reports Server (NTRS)

    Dillon, J. N.

    1967-01-01

    Photosensitive filler is added to curable epoxy resins to minimize stress from internal shrinkage during curing or polymerization. Cinnamic acid resins and cinnamal ketones may be added in the amount of 1 to 3 percent by weight of the resin mixture.

  3. Wood ants use resin to protect themselves against pathogens

    E-print Network

    Lehmann, Laurent

    al. 2003b). Coniferous resin contains a complex mixture of terpenes that protects wounded treesWood ants use resin to protect themselves against pathogens Michel Chapuisat1,*, Anne Oppliger2. Wood ants, Formica paralugubris, commonly bring back pieces of solidified coniferous resin

  4. Remote Monitoring of Resin Transfer Molding Processes by Distributed

    E-print Network

    Mamishev, Alexander

    of cure of the resin as it is injected into the mold. Successful implementation of a sensing systemRemote Monitoring of Resin Transfer Molding Processes by Distributed Dielectric Sensors MICHAEL C, 2003) (Accepted November 8, 2004) ABSTRACT: Feed-forward adaptive control of resin transfer molding

  5. Low-melt Viscosity Polyimide Resins for Resin Transfer Molding (RTM) II

    NASA Technical Reports Server (NTRS)

    Chuang, Kathy C.; Criss, Jim M.; Mintz, Eric A.; Scheiman, Daniel A.; Nguyen, Baochau N.; McCorkle, Linda S.

    2007-01-01

    A series of polyimide resins with low-melt viscosities in the range of 10-30 poise and high glass transition temperatures (Tg s) of 330-370 C were developed for resin transfer molding (RTM) applications. These polyimide resins were formulated from 2,3,3 ,4 -biphenyltetracarboxylic dianhydride (a-BPDA) with 4-phenylethynylphthalic anhydride endcaps along with either 3,4 - oxyaniline (3,4 -ODA), 3,4 -methylenedianiline, (3,4 -MDA) or 3,3 -methylenedianiline (3,3 -MDA). These polyimides had pot lives of 30-60 minutes at 260-280 C, enabling the successful fabrication of T650-35 carbon fiber reinforced composites via RTM process. The viscosity profiles of the polyimide resins and the mechanical properties of the polyimide carbon fiber composites will be discussed.

  6. Methyl Jasmonate Induces Traumatic Resin Ducts, Terpenoid Resin Biosynthesis, and Terpenoid Accumulation in Developing Xylem of Norway Spruce Stems

    Microsoft Academic Search

    Diane Martin; Dorothea Tholl; Jonathan Gershenzon; Jorg Bohlmann

    2002-01-01

    Norway spruce (Picea abies L. Karst) produces an oleoresin characterized by a diverse array of terpenoids, monoterpenoids, sesquiterpenoids, and diterpene resin acids that can protect conifers against potential herbivores and pathogens. Oleoresin accumulates constitutively in resin ducts in the cortex and phloem (bark) of Norway spruce stems. De novo formation of traumatic resin ducts (TDs) is observed in the developing

  7. Computational Modeling of theComputational Modeling of the Vacuum Assisted Resin Transfer MoldingVacuum Assisted Resin Transfer Molding

    E-print Network

    Grujicic, Mica

    Computational Modeling of theComputational Modeling of the Vacuum Assisted Resin Transfer MoldingVacuum Assisted Resin Transfer Molding (VARTM) Process(VARTM) Process April 2004April 2004 DepartmentMS Thesis Advisor: Dr. Grujicic #12;What is VARTM?What is VARTM? Vacuum Assisted Resin Transfer Molding

  8. Effect of resin thickness on the microhardness and optical properties of bulk-fill resin composites

    PubMed Central

    Kim, Eun-Ha; Jung, Kyoung-Hwa; Son, Sung-Ae; Hur, Bock; Kwon, Yong-Hoon

    2015-01-01

    Objectives This study evaluated the effects of the resin thickness on the microhardness and optical properties of bulk-fill resin composites. Methods Four bulk-fill (Venus Bulk Fill, Heraeus Kulzer; SDR, Dentsply Caulk; Tetric N-Ceram Bulk Fill, Ivoclar vivadent; SonicFill, Kerr) and two regular resin composites (Charisma flow, Heraeus Kulzer; Tetric N-Ceram, Ivoclar vivadent) were used. Sixty acrylic cylindrical molds were prepared for each thickness (2, 3 and 4 mm). The molds were divided into six groups for resin composites. The microhardness was measured on the top and bottom surfaces, and the colors were measured using Commission Internationale d'Eclairage (CIE) L*a*b* system. Color differences according to the thickness and translucency parameters and the correlations between the microhardness and translucency parameter were analyzed. The microhardness and color differences were analyzed by ANOVA and Scheffe's post hoc test, and a student t-test, respectively. The level of significance was set to ? = 0.05. Results The microhardness decreased with increasing resin thickness. The bulk-fill resin composites showed a bottom/top hardness ratio of almost 80% or more in 4 mm thick specimens. The highest translucency parameter was observed in Venus Bulk Fill. All resin composites used in this study except for Venus Bulk Fill showed linear correlations between the microhardness and translucency parameter according to the thickness. Conclusions Within the limitations of this study, the bulk-fill resin composites used in this study can be placed and cured properly in the 4 mm bulk. PMID:25984474

  9. Micro-tensile bond testing of resin cements to dentin and an indirect resin composite

    Microsoft Academic Search

    Yiu-Fai Mak; Shirley C. N Lai; Gary S. P Cheung; Alex W. K Chan; Franklin R Tay; David H Pashley

    2002-01-01

    Objectives: Micro-tensile bond strength (?TBS) evaluation and fractographic analysis were used to compare four resin cement systems (AC: All-Bond 2\\/Choice; RX: Single Bond\\/RelyX ARC; SB: Super-Bond C&B; and PF: Panavia F) in indirect composite\\/dentin adhesive joints.Methods: Flat dentin surfaces were created on extracted human third molars. The resin cements were used according to the manufacturers' instructions for bonding silanized composite

  10. Modification of Epoxy Resin by Cyanate Ester Resin and Liquid Butadiene-Acrylonitrile Rubbers

    Microsoft Academic Search

    Xudong Sun; Minfeng Zeng; Cuiyun Lu; Fengyuan Yan; Chenze Qi

    2010-01-01

    In this paper, the results showed that the addition of an appropriate amount of reactive rubbers ((ie: carboxyl randomized butadiene-acrylonitrile rubber (CRBN) and hydroxyl terminated butadiene-acrylonitrile rubber (HTBN)) to epoxy resin\\/cyanate ester resin (EP\\/CE) (70\\/30) improved both the mechanical properties and thermal stability of the resulting blends. CRBN and HTBN have different reactive activity and dispersion state in EP\\/CE\\/rubbers. No

  11. Resin char oxidation retardant for composites

    NASA Technical Reports Server (NTRS)

    Bowles, K. J.; Gluyas, R. E.

    1981-01-01

    Boron powder stabilizes char, so burned substances are shiny, smooth, and free of loose graphite fibers. Resin weight loss of laminates during burning in air is identical for the first three minutes for unfilled and boron-filled samples, then boron samples stabilize.

  12. Fiber reinforced thermoplastic resin matrix composites

    NASA Technical Reports Server (NTRS)

    Jones, Robert J. (Inventor); Chang, Glenn E. C. (Inventor)

    1989-01-01

    Polyimide polymer composites having a combination of enhanced thermal and mechanical properties even when subjected to service temperatures as high as 700.degree. F. are described. They comprise (a) from 10 to 50 parts by weight of a thermoplastic polyimide resin prepared from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and (b) from 90 to 50 parts by weight of continuous reinforcing fibers, the total of (a) and (b) being 100 parts by weight. Composites based on polyimide resin formed from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and pyromellitic dianhydride and continuous carbon fibers retained at least about 50% of their room temperature shear strength after exposure to 700.degree. F. for a period of 16 hours in flowing air. Preferably, the thermoplastic polyimide resin is formed in situ in the composite material by thermal imidization of a corresponding amide-acid polymer prepared from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane. It is also preferred to initially size the continuous reinforcing fibers with up to about one percent by weight of an amide-acid polymer prepared from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane. In this way imidization at a suitable elevated temperature results in the in-situ formation of a substantially homogeneous thermoplastic matrix of the polyimide resin tightly and intimately bonded to the continuous fibers. The resultant composites tend to have optimum thermo-mechanical properties.

  13. Pharmaceutical Applications of Ion-Exchange Resins

    ERIC Educational Resources Information Center

    Elder, David

    2005-01-01

    The historical uses of ion-exchanged resins and a summary of the basic chemical principles involved in the ion-exchanged process are discussed. Specific applications of ion-exchange are provided that include drug stabilization, pharmaceutical excipients, taste-masking agents, oral sustained-release products, topical products for local application…

  14. Epoxy resins produce improved plastic scintillators

    NASA Technical Reports Server (NTRS)

    Markley, F. W.

    1967-01-01

    Plastic scintillator produced by the substitution of epoxy resins for the commonly used polystyrene is easy to cast, stable at room temperature, and has the desirable properties of a thermoset or cross-linked system. Such scintillators can be immersed directly in strong solvents, an advantage in many chemical and biological experiments.

  15. Novel processing of epoxy resin systems

    Microsoft Academic Search

    C. A. May; W. Breitigam; R. S. Bauer

    1993-01-01

    The laminates that are used to prepare advanced composite parts generally require curing at high temperature and pressure, and their raw material shelf lives are limited. The epoxy resin systems that the authors describe here offer the potential of extended shelf life while curing at relatively low temperatures with a method the authors call rapid thermoset processing (RTP). A laminate

  16. RESIN TRANSFER MOLDING PROCESS MONITORING AND CONTROL

    Microsoft Academic Search

    C. William Lee; Brian P. Rice; Matthew B. Buczek; David C. Mason

    Resin Transfer Molding (RTM) offers the opportunity for significant cost savings in the fabrication of polymer matrix composite aerospace structures. However, the realization of this cost savings has been restricted by quality problems, such as voids, poor fiber volume control, etc., that are inherent to the RTM process. Similar quality issues in autoclave processes have benefited from the use of

  17. Water durability of resin bond to precious metal alloys using adhesive resins containing adhesion promoting monomers.

    PubMed

    Kadoma, Yoshinori; Kojima, Katsunori

    2005-12-01

    Adhesive resins for precious metals were prepared by adding an adhesion promoting monomer to MMA-PMMA/TBBO resin. Precious metal alloys bonded by the adhesive resin were thermocycled 0, 1,000, 2,000, or 4,000 times in water between 4 and 60 degrees C, and tensile bond strengths were measured. Debonded metal surfaces after the tensile test were analyzed based on an area of cohesive failure. Three-way ANOVA revealed that all the three parameters--adherend, adhesive monomer, and number of thermal cycles--exhibited a significant influence on bond strength. Bond strength significantly decreased with increasing number of thermal cycles except for resin with 9,10-epithiodecyl 4-vinylbenzoate (EP8VB) to Au alloy. Mean bond strength of adhesive resin with 9,10-epithiodecyl methacrylate (EP8MA), EP8VB, or 3,4-epithiobutyl 2,2-bis(methacryloyloxymethyl)propionate (EP2BMA) exceeded 22 MPa after 4,000 thermal cycles. Analysis of debonded surfaces revealed the applicability of EP8MA, EP8VB, and EP2BMA as an adhesive monomer component of adhesive resin formulations. PMID:16445009

  18. Resin film infusion mold tooling and molding method

    NASA Technical Reports Server (NTRS)

    Burgess, Roger (Inventor); Grossheim, Brian (Inventor); Mouradian, Karbis (Inventor); Thrash, Patrick J. (Inventor)

    1999-01-01

    A mold apparatus and method for resin film infusion molding including an outer mold tool having a facing sheet adapted to support a resin film and preform assembly. The facing sheet includes attachment features extending therefrom. An inner mold tool is positioned on the facing sheet to enclose the resin film and preform assembly for resin film infusion molding. The inner mold tool includes a plurality of mandrels positioned for engagement with the resin film and preform assembly. Each mandrel includes a slot formed therein. A plurality of locating bars cooperate with the slots and with the attachment features for locating the mandrels longitudinally on the outer mold tool.

  19. Stability Of A Carbon-Dioxide-Removing Resin

    NASA Technical Reports Server (NTRS)

    Wydeven, Theodore; Wood, Peter

    1990-01-01

    Report describes experiments determing long-term chemical stability of IRA-45, commerical ion-exchange resin candidate for use in removing CO2 from atmosphere of Space Station. In proposed system, cabin air passes through resin, and acidic CO2 absorbed by weakly-basic hydrated diethylenetriamine bonded to porous resin substrate. When resin absorbs all CO2, disconnects from airstream and heated with steam to desorb CO2. Resin reuseable. Removed by post-treating process air with phosphoric acid on charcoal. Other chemicals removed by trace-contaminant-control subsystem of Space Station.

  20. ANALYSIS OF VENTING OF A RESIN SLURRY

    SciTech Connect

    Laurinat, J.; Hensel, S.

    2012-03-27

    A resin slurry venting analysis was conducted to address safety issues associated with overpressurization of ion exchange columns used in the Purex process at the Savannah River Site (SRS). If flow to these columns were inadvertently interrupted, an exothermic runaway reaction could occur between the ion exchange resin and the nitric acid used in the feed stream. The nitric acid-resin reaction generates significant quantities of noncondensable gases, which would pressurize the column. To prevent the column from rupturing during such events, rupture disks are installed on the column vent lines. The venting analysis models accelerating rate calorimeter (ARC) tests and data from tests that were performed in a vented test vessel with a rupture disk. The tests showed that the pressure inside the test vessel continued to increase after the rupture disk opened, though at a slower rate than prior to the rupture. Calculated maximum discharge rates for the resin venting tests exceeded the measured rates of gas generation, so the vent size was sufficient to relieve the pressure in the test vessel if the vent flow rate was constant. The increase in the vessel pressure is modeled as a transient phenomenon associated with expansion of the resin slurry/gas mixture upon rupture of the disk. It is postulated that the maximum pressure at the end of this expansion is limited by energy minimization to approximately 1.5 times the rupture disk burst pressure. The magnitude of this pressure increase is consistent with the measured pressure transients. The results of this analysis demonstrate the need to allow for a margin between the design pressure and the rupture disk burst pressure in similar applications.

  1. Synthesis and characterizations of melamine-based epoxy resins.

    PubMed

    Ricciotti, Laura; Roviello, Giuseppina; Tarallo, Oreste; Borbone, Fabio; Ferone, Claudio; Colangelo, Francesco; Catauro, Michelina; Cioffi, Raffaele

    2013-01-01

    A new, easy and cost-effective synthetic procedure for the preparation of thermosetting melamine-based epoxy resins is reported. By this innovative synthetic method, different kinds of resins can be obtained just by mixing the reagents in the presence of a catalyst without solvent and with mild curing conditions. Two types of resins were synthesized using melamine and a glycidyl derivative (resins I) or by adding a silane derivative (resin II). The resins were characterized by means of chemical-physical and thermal techniques. Experimental results show that all the prepared resins have a good thermal stability, but differ for their mechanical properties: resin I exhibits remarkable stiffness with a storage modulus value up to 830 MPa at room temperature, while lower storage moduli were found for resin II, indicating that the presence of silane groups could enhance the flexibility of these materials. The resins show a pot life higher than 30 min, which makes these resins good candidates for practical applications. The functionalization with silane terminations can be exploited in the formulation of hybrid organic-inorganic composite materials. PMID:24013372

  2. Electrically conductive resinous bond and method of manufacture

    DOEpatents

    Snowden, T.M. Jr.; Wells, B.J.

    1985-01-01

    A method of bonding elements together with a bond of high strength and good electrical conductivity which comprises: applying an unfilled polyimide resin between surfaces of the elements to be bonded, heat treating said unfilled polyimide resin in stages between a temperature range of about 40 to 365/sup 0/C to form a strong adhesive bond between said elements, applying a metal-filled polyimide resin overcoat between said elements so as to provide electrical connection therebetween, and heat treating said metal-filled polyimide resin with substantially the same temperature profile as the unfilled polyimide resin. The present invention is also concerned with an adhesive, resilient, substantially void free bonding combination for providing a high strength, electrically conductive adhesive attachment between electrically conductive elements which comprises a major amount of an unfilled polyimide resin and a minor amount of a metal-filled polyimide resin.

  3. Technique for removing resin from a molded object

    NASA Technical Reports Server (NTRS)

    Hemmi, I.; Morishita, T.; Ono, T.

    1983-01-01

    Resin is removed from a molded object in such a way that no cracks or expansion occurs in the casting. The resin is first mixed with a ceramics powder or metal powder. This mixture is then molded and the resin is removed by heat. The molded object is then placed into a container which is sealed and large enough to allow the gas from the resin to be controlled by heat from the resin. The gas pressure at the surface of the object is increased by the gas pressure generated from the resin and the resin removed. The increase in gas pressure from the surface of the molded object is 1.5 atm to 3 atm at 350 C to 400 C.

  4. Electrically conductive resinous bond and method of manufacture

    DOEpatents

    Snowden, Jr., Thomas M. (P.O. Box 4231, Clearwater, FL 33518); Wells, Barbara J. (865 N. Village Dr., Apt. 101B, St. Petersburg, FL 33702)

    1987-01-01

    A method of bonding elements together with a bond of high strength and good electrical conductivity which comprises: applying an unfilled polyimide resin between surfaces of the elements to be bonded, heat treating said unfilled polyimide resin in stages between a temperature range of about 40.degree. to 365.degree. C. to form a strong adhesive bond between said elements, applying a metal-filled polyimide resin overcoat between said elements so as to provide electrical connection therebetween, and heat treating said metal-filled polyimide resin with substantially the same temperature profile as the unfilled polyimide resin. The present invention is also concerned with an adhesive, resilient, substantially void free bonding combination for providing a high strength, electrically conductive adhesive attachment between electrically conductive elements which comprises a major amount of an unfilled polyimide resin and a minor amount of a metal-filled polyimide resin.

  5. Improvement of physical and biological properties of particleboards by impregnation with phenolic resin

    Microsoft Academic Search

    Hiromu Kajita; Yuji Imamura

    1991-01-01

    Particleboards were treated with a low molecular-weight phenol-formaldehyde resin and their properties were evaluated. Particles were dipped into aqueous solutions of resin or sprayed with resin solutions before spraying the conventional phenol-formaldehyde resin adhesive, or sprayed with a mixture of low molecular-weight resin and the adhesive resin in a single step. Though mechanical properties and dimensional stability of the phenolic-resin-treated

  6. Flammability of Epoxy Resins Containing Phosphorus

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Thompson, C. M.; Smith, J. G.; Connell, J. W.; Hinkley, J. A.

    2005-01-01

    As part of a program to develop fire-resistant exterior composite structures for future subsonic commercial and general aviation aircraft, flame-retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured neat epoxy formulations were characterized by thermogravimetric analysis, propane torch test, elemental analysis, microscale combustion calorimetry, and fire calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness and compressive strength of several cured formulations showed no detrimental effect due to phosphorus content. The chemistry and properties of these new epoxy formulations are discussed.

  7. Ethynylated aromatics as high temperature matrix resins

    NASA Technical Reports Server (NTRS)

    Hurwitz, Frances I.

    1986-01-01

    Difunctional and trifunctional arylacetylenes were used as monomers to form thermoset matrix resin composites. Composites can be hot pressed at 180 C to react 80 percent of the acetylene groups. Crosslinking is completed by postcuring at 350 C. The postcured resins are thermally stable to nominally 460 C in air. As a result of their high crosslink density, the matrix exhibits brittle failure when unaxial composites are tested in tension. Failure of both uniaxial tensile and flexural specimens occurs in shear at the fiber matrix interface. Tensile fracture stresses for 0 deg composites fabricated with 60 v/o Celion 6K graphite fiber were 827 MPa. The strain to failure was 0.5 percent. Composites fabricated with 8 harness satin Celion cloth (Fiberite 1133) and tested in tension also failed in shear at tensile stresses of 413 MPa.

  8. Fire- and Heat-Resistant Laminating Resins

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.; Mikroyannidis, John A.

    1987-01-01

    Imide compounds containing phosphourus thermally polymerized. New maleimido- or citraconimido-end-capped monomers, have relatively low melting temperatures, polymerized at moderate temperatures to rigid bisimide resins without elimination of volatiles. Monomers dissolve in such solvents as methyl ethyl ketone, acetone, and tetrahydrofuran, suitable and perferred as "varnish solvents" for composite fabrication. Low melting points of these componds allow use as adhesives without addition of solvents.

  9. Thermochemical study of behavior of petroleum resins

    Microsoft Academic Search

    E. N. Sazonova; M. Yu. Mashkov; A. A. Velikov; N. V. Yudina

    1988-01-01

    The stability of petroleum disperse systems and the structural-mechanical properties of these systems are determined mainly by the presence of high-molecular-weight waxes, asphaltenes, and resins, which form complex structural units (CSUs) in the system. The influence of the energy of intermolecular interaction (IMI) on the formation of associates has not yet been thoroughly evaluated, although an important role has been

  10. Processable polyimide adhesive and matrix composite resin

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (inventor); St.clair, Terry L. (inventor); Progar, Donald J. (inventor)

    1990-01-01

    A high temperature polyimide composition prepared by reacting 4,4'-isophthaloyldiphthalic anhydride with metaphenylenediamine is employed to prepare matrix resins, adhesives, films, coatings, moldings, and laminates, especially those showing enhanced flow with retention of mechanical and adhesive properties. It can be used in the aerospace industry, for example, in joining metals to metals or metals to composite structures. One area of application is in the manufacture of lighter and stronger aircraft and spacecraft structures.

  11. Modified melamine resins for optical applications

    NASA Astrophysics Data System (ADS)

    Mahler, Joachim; Rafler, Gerald

    1999-06-01

    A new four-step synthetic-route for combining chromophores with melamine resins was developed and their use for optical applications was demonstrated. Despite other melamine resins, the basic molecule of this system is the 2,4,6-trichloro-1,3,5-triazine, the cyanuric chloride. In the first step, the azochromophore was bonded to the s-triazine-ring. Then the residual chlorines of this triazine-chromophore were substituted by ammonia or primary amines. In the third step formaldehyde was added, leading to melamine-chromophore precondensates. For increasing the stability and the solubility of these precondensates, the reactive methylolgroups were etherificated with methyl or butyl alcohol. One example of such a crosslinkable melamine-chromophore was illustrated and characterized by NMR- and mass-spectroscopy. The mass-spectrum gives evidence that the modified melamine precondensates are monomers and not a mixture of different oligomers like else in melamine-aldehyde prepolymers. The result of these systems is a crosslinkable melamine-chromophore monomer which is converted in a resin by thermal treating or by acids. It is remarkable that these polymers show an excellent thermal stability with a de-composition temperature beyond 300°C, a great advantage for using them as optical materials. Their usability as second-order nonlinear optical material was investigated by corona poling.

  12. Composite fabrication via resin transfer molding technology

    SciTech Connect

    Jamison, G.M.; Domeier, L.A.

    1996-04-01

    The IMPReS (Integrated Modeling and Processing of Resin-based Structures) Program was funded in FY95 to consolidate, evaluate and enhance Sandia`s capabilities in the design and fabrication of composite structures. A key driver of this and related programs was the need for more agile product development processes and for model based design and fabrication tools across all of Sandia`s material technologies. A team of polymer, composite and modeling personnel was assembled to benchmark Sandia`s existing expertise in this area relative to industrial and academic programs and to initiate the tasks required to meet Sandia`s future needs. RTM (Resin Transfer Molding) was selected as the focus composite fabrication technology due to its versatility and growing use in industry. Modeling efforts focused on the prediction of composite mechanical properties and failure/damage mechanisms and also on the uncured resin flow processes typical of RTM. Appropriate molds and test composites were fabricated and model validation studies begun. This report summarizes and archives the modeling and fabrication studies carried out under IMPReS and evaluates the status of composite technology within Sandia. It should provide a complete and convenient baseline for future composite technology efforts within Sandia.

  13. Kinetic modelling of vinyl ester resin polymerization

    SciTech Connect

    Dhulipala, R.; Kreig. G.; Hawley, M.C. [Michigan State Univ., East Lansing, MI (United States)

    1993-12-31

    The study of kinetics offers a substantional incentive in the endeavor to manufacture polymer matrix composites at high speeds. The study enables one to optimize the curing cycle based on the specific curing characteristics of the resin and also makes it possible to simulate the curing process. This paper reports the results of the modelling of the thermal curing of the vinyl ester resin. The parameters for the proposed model have been calculated based on conversion-vs-data generated at various temperatures and Benzoyl peroxide (initiator) concentrations. The extent of cure of the resin mixture was determined using Fourier Transform Infrared Spectroscopy. In this model the termination rate constant is considered to drop with extent of cure until a limiting value is reached. The limiting value is a consequence of the active chain ends possessing a degree of mobility due to the propagation reaction even though the translational motion of the growing for radicals in increasingly restricted with conversion. Good agreements is observed between the model predictions and the experimental data.

  14. Chemoviscosity modeling for thermosetting resins - I

    NASA Technical Reports Server (NTRS)

    Hou, T. H.

    1984-01-01

    A new analytical model for chemoviscosity variation during cure of thermosetting resins was developed. This model is derived by modifying the widely used WLF (Williams-Landel-Ferry) Theory in polymer rheology. Major assumptions involved are that the rate of reaction is diffusion controlled and is linearly inversely proportional to the viscosity of the medium over the entire cure cycle. The resultant first order nonlinear differential equation is solved numerically, and the model predictions compare favorably with experimental data of EPON 828/Agent U obtained on a Rheometrics System 4 Rheometer. The model describes chemoviscosity up to a range of six orders of magnitude under isothermal curing conditions. The extremely non-linear chemoviscosity profile for a dynamic heating cure cycle is predicted as well. The model is also shown to predict changes of glass transition temperature for the thermosetting resin during cure. The physical significance of this prediction is unclear at the present time, however, and further research is required. From the chemoviscosity simulation point of view, the technique of establishing an analytical model as described here is easily applied to any thermosetting resin. The model thus obtained is used in real-time process controls for fabricating composite materials.

  15. Correlations of norbornenyl crosslinked polyimide resin structures with resin thermo-oxidative stability, resin glass transition temperature and composite initial mechanical properties

    NASA Technical Reports Server (NTRS)

    Alston, William B.

    1988-01-01

    PMR (polymerization of monomeric reactants) methodology was used to prepare 70 different polyimide oligomeric resins and 30 different unidirectional graphite fiber/polyimide composites. Monomeric composition as well as chain length between sites of crosslinks were varied to examine their effects on resin thermo-oxidative stability and glass transition temperature (Tg) of the cured/postcured resins. A linear correlation of decreasing 316 C resin weight loss/surface area versus (1) decreasing aliphatic content, or (2) increasing benzylic/aliphatic content stoichiometry ratio over a wide range of resin compositions was observed. An almost linear correlation of Tg versus molecular distance between the crosslinks was also observed. An attempt was made to correlate Tg with initial composite mechanical properties (flexural strength and interlaminar shear strength). However, the scatter in mechanical strength data prevented obtaining a clear correlation. Instead, only a range of composite mechanical properties was obtained at 25, 288, and 316 C. Perhaps more importantly, what did become apparent during the correlation study was (1) the PMR methodology could be used to prepare composites from resins containing a wide variety of monomer modifications, (2) that these composites almost invariably provided satisfactory initial mechanical properties as long as the resins formulated exhibited satisfactory processing flow, and (3) that PMR resins exhibited predictable rates of 316 C weight loss/surface area based on their benzylic/aliphatic stoichiometery ratio.

  16. Treatment of radioactive ionic exchange resins by super- and sub-critical water oxidation (SCWO)

    Microsoft Academic Search

    Kyeongsook Kim; Soon Hwan Son; KwangSin Kim; Joo Hee Han; Kee Do Han; Seung Hoe Do

    2010-01-01

    As the usage of ion exchange resins increases the inventory of spent ion exchange resins increases in nuclear power plants. This study is to find an environmental-friendly process to treat theses spent resins. The test samples were prepared by diluting the slurry made by wet ball milling the spent cationic exchange resins for 24h. The spent cationic exchange resins were

  17. Machine for applying a two component resin to a roadway surface

    DOEpatents

    Huszagh, D.W.

    1984-01-01

    A portable machine for spraying two component resins onto a roadway, the machine having a pneumatic control system, including means for purging the machine of mixed resin with air and then removing remaining resin with solvent. Interlocks prevent contamination of solvent and resin, and mixed resin can be purged in the event of a power failure.

  18. Investigation of the curing kinetics of alkyd–melamine–epoxy resin system

    Microsoft Academic Search

    Suzana M. Caki?; Ivan S. Risti?; Vladislav M. Jašo; Radmila Ž. Radi?evi?; Olivera Z. Ili?; Jaroslava K. B. Simendi?

    Properties of coatings based on alkyd resin can be improved via blending with other suitable resins. Recent studies assessed that many properties could be improved by blending with epoxy resins as well as with melamine resins. The aim of this work was to investigate the effect of epoxy resin content on the curing process in alkyd–melamine–epoxy three component blends. The

  19. A high photosensitive IL-CCD image sensor with monolithic resin lens array

    Microsoft Academic Search

    Y. Ishihara; K. Tanigaki

    1983-01-01

    A high photosensitivity interline transfer CCD image sensor with monolithic resin lens array was developed. The resin lens array was made on the 2\\/3 inch scheme 768(H) × 490(V) pixels interline CCD image sensor by using the resin thermal flow technique. The resin lens array consists of a smooth base resin layer and overlaid vertical stripe semicylindrical lens array corresponding

  20. CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN

    SciTech Connect

    Nash, C.; Duignan, M.

    2010-02-23

    This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two {approx}11 mL beds in columns in a lead-lag arrangement. The first two campaigns used Savannah River Site (SRS) Tank 2F nonradioactive simulant while the latter two were fed with actual dissolved salt in the Savannah River National Laboratory (SRNL) Shielded Cells. Both radioactive cycles ran to cesium breakthrough of the lead column. The resin beds saw in excess of 400 bed volumes of feed in each cycle. Resin disposal plans in tank farm processing depend on characterizations of resin used with actual tank feed. Following a final 30 bed volume (BV) elution with nitric acid, the resin beds were found to contain detectable chromium, barium, boron, aluminum, iron, sodium, sulfur, plutonium, cesium, and mercury. Resin affinity for plutonium is important in criticality safety considerations. Cesium-137 was found to be less than 10E+7 dpm/g of resin, similar to past work with sRF resin. Sulfur levels are reasonably consistent with other work and are expected to represent sulfur chemistry used in the resin manufacture. There were low but detectable levels of technetium, americium, and curium. Toxicity Characteristic Leaching Procedure (TCLP) work on the used (eluted) resin samples showed significant contents of mercury, barium, and chromium. One resin sample exceeded the TCLP level for mercury while the other metals were below TCLP levels. TCLP organics measurements indicated measurable benzene in one case, though the source was unknown. Results of this work were compared with other work on similar sRF resin characterizations in this report. This is the first work to quantify mercury on sRF resin. Resin mercury content is important in plans for the disposition of used sRF resin. Mercury speciation in high level waste (HLW) is unknown. It may be partly organic, one example being methyl mercury cation. Further study of the resin's affinity for mercury is recommended.

  1. Effects of layering technique on the shade of resin overlays and the microhardness of dual cure resin cement.

    PubMed

    Chang, Hoon-Sang; Hong, Sung-Ok

    2014-01-01

    The purpose of this study was to assess the color of layered resin overlays and to test the early microhardness of dual cure resin cement (DCRC) light cured through the layered resin overlays. Resin overlays of 1.5 mm thickness were fabricated with the A3 shade of Z350 (Group 1L), the A3B and A3E shades of Supreme XT (Group 2L), and the A3, E3, and T1 shades of Sinfony (Group 3L) using one, two, and three layers, respectively (n=7). Each layer of the resin overlays was set in equal thickness. The color of the resin overlays was measured with a colorimeter and compared with an A3 shade resin denture tooth. DCRC was light cured through the resin overlays, and the early microhardness of the DCRC was measured. The ?E value between the denture tooth and the resin overlays and the Vickers hardness number (VHN) of the DCRC were analyzed with one-way ANOVA and Tukey's HSD test. The color differences were 8.9±0.5, 5.3±1.0, and 7.3±0.5 and the VHNs were 19.4±1.1, 21.1±0.9, and 29.3±0.6 for Groups 1L, 2L, and 3L, respectively. Therefore, to match the designated tooth color of resin inlays and to increase the early microhardness of DCRC, layered resin inlays are more appropriate than single-dentin-layer resin inlays. However, the translucent layer should be used cautiously because the color difference of resin inlays with a translucent layer was affected more than those without a translucent layer. PMID:24918368

  2. Health Problems of Epoxy Resins and Amine-curing Agents

    PubMed Central

    Bourne, L. B.; Milner, F. J. M.; Alberman, K. B.

    1959-01-01

    Epoxy resins were first introduced about 10 years ago. Toxic effects, particularly dermatitis, have been frequently described. An investigation into the possible causes of pathological sequelae following the use of epoxy resin/amine mixtures has been undertaken. The cause of most cases of dermatitis and sensitization appears to be uncombined amine which is present in recent mixtures and persists in hardened resin for long periods. The results of experiments with two of the most commonly used resin/amine mixtures confirm this. Cold-cured resins are more dangerous and remain so even when hardened. A simple theory is suggested for the mechanism of the reaction between epoxy resins, amines, and biological systems. This theory leads logically to the handling precautions outlined. Images PMID:13651551

  3. Inorganic resins for clinical use of .sup.213Bi generators

    DOEpatents

    DePaoli, David W. (Knoxville, TN); Hu, Michael Z. (Knoxville, TN); Mirzadeh, Saed (Knoxville, TN); Clavier, John W. (Elizabethton, TN)

    2011-03-29

    Applicant's invention is a radionuclide generator resin material for radiochemical separation of daughter radionuclides, particularly .sup.213Bi, from a solution of parental radionuclides, the resin material capable of providing clinical quantities of .sup.213Bi of at least 20-mCi, wherein the resin material comprises a silica-based structure having at least one bifunctional ligand covalently attached to the surface of the silica-based structure. The bifunctional ligand comprises a chemical group having desirable surface functionality to enable the covalent attachment of the bifunctional ligand thereon the surface of the structure and the bifunctional ligand further comprises a second chemical group capable of binding and holding the parental radionuclides on the resin material while allowing the daughter radionuclides to elute off the resin material. The bifunctional ligand has a carbon chain with a limited number of carbons to maintain radiation stability of the resin material.

  4. Bismaleimide resins for flame resistant honeycomb sandwich panels

    NASA Technical Reports Server (NTRS)

    Stenzenberger, H. D.

    1978-01-01

    Bismaleimide resins are prime candidates for nonflammable aircraft interior panels. Three resin types with different structures and processing characteristics were formulated. Resin M 751 was used to fabricate 100 kg of glass fabric prepregs which were used for the preparation of face sheets for honeycomb sandwich panels. Prepreg characteristics and curing cycles for laminate fabrication are provided. In order to advance beyond the current solvent resin technology for fibre and fabric impregnation, a hot melt solvent-less resin system was prepared and characterized. Preliminary tests were performed to develop a wet bonding process for the fabrication of advanced sandwich honeycomb panels by use of polybismaleimide glass fabric face sheets and polybismaleimide Nomex honeycomb core. B-stage material was used for both the core and the face sheet, providing flatwise tensile properties equivalent to those obtained by the state-of-the-art 3-step process which includes an epoxy adhesive resin.

  5. Resin impregnation during the manufacturing of composite materials

    SciTech Connect

    Coulter, J.P.

    1988-01-01

    A numerical and experimental study of resin-impregnation processes during the manufacturing of composite materials was performed. A formulation of the problem was accomplished using ideas taken from the theory of flow through anisotropic porous media. A treatment of the resin-impregnation front that exists during impregnation processes was also suggested. Using these ideas, a methodology for simulating two-dimensional isothermal resin-impregnation processes under conditions of specified injection rate or specified applied pressure was developed. Special attention was directed at the simulation of resin-transfer modeling and resin film stacking/compression modeling processes. Due to the geometrical complexity of the situations to be modeled, the computational technique of boundary-fitted coordinate systems encompassing numerical grid generation was chosen. It was found that the simulation of impregnation under specified applied-pressure loading conditions is much more involved than that of the specified resin injection rate conditions.

  6. CCMR: Green Composites: Using Modified Sunflower Based Resins

    NSDL National Science Digital Library

    Yarbrough, DeAnna S.

    2010-08-15

    In this research, green composites were developed using sunflower based resins and jute fabric material. More specifically, research was done on the effects of modification on the mechanical properties of the resin. By incorporating modified sunflower based resin, the protein content increases, which therefore enhance the mechanical properties. Modifying the resin by changing the pH, using a micro fabric filtration, and applying recycled newspaper fibers all enhance the young’s modulus, tensile stress, and tensile strain of the sunflower plant based resin. As more research on how to increase the properties of the resin develop, the more likely green composites can be used throughout society as biodegradable, renewable materials, rather than petroleum-based materials.

  7. Internal stabilization of polycarbonate resins by two stage radiation process

    NASA Technical Reports Server (NTRS)

    Gupta, Amitava (Inventor); Liang, Ranty H. (Inventor); Yavrouian, Andre H. (Inventor)

    1988-01-01

    A new polycarbonate copolymer resin is formed by internal generation of stabilizers bound to the polymer chain. Irradiation of a solid piece or a deoxygenated solution of the resin at a first frequency below 300 nm generates 2 to 8 mol percent of phenyl salicylate groups which are rearranged to dihydroxybenzophenone groups by irradiating the resin under oxygen excluding conditions at a second frequency from 300 to 320 nm.

  8. Chromium Ions Improve Moisure Resistance of Epoxy Resins

    NASA Technical Reports Server (NTRS)

    St. Clair, A. K.; St. Clair, T. L.; Stoakley, D. M.; Singh, J. J.; Sprinkle, D. R.

    1986-01-01

    Broad spectrum of thermosetting epoxy resins used on commercial and military aircraft, primarily as composite matrices and adhesives. In new technique, chromium-ion containing epoxy with improved resistance to moisture produced where chromium ions believed to prevent absorption of water molecules by coordinating themselves to hydroxyl groups on epoxy chain. Anticipated that improved epoxy formulation useful as composite matrix resin, adhesive, or casting resin for applications on commercial and advanced aircraft. Improvement made without sacrifice in mechanical properties of polymer.

  9. Micromechanical properties of veneer luting resins after curing through ceramics

    Microsoft Academic Search

    Elif Öztürk; Reinhard Hickel; ?ükran Bolay; Nicoleta Ilie

    The aim of this study was to assess the performance of light-cured luting resin after curing under the ceramic restoration\\u000a in comparison to dual-cured luting resin, by evaluating the micromechanical properties. Two hundred seventy thin luting composite\\u000a films of ca. 170 ?m in thickness were prepared by using two light-cured luting resins (Variolink Veneer, Ivoclar Vivadent;\\u000a RelyX Veneer, 3M ESPE) and

  10. Evaluation of Elution Parameters for Cesium Ion Exchange Resins

    Microsoft Academic Search

    Ingrid E. Burgeson; Jaquetta R. Deschane; Bryan J. Cook; David L. Blanchard; Dennis R. Weier

    2006-01-01

    Cesium ion exchange is one of the planned processes for treating and disposing of waste at the U.S. Department of Energy Hanford Site. Radioactive supernatant liquids from the waste tanks will undergo ultrafiltration, followed by cesium ion exchange using a regenerable organic ion exchange resin. Two resins, SuperLig644 and a resorcinol?formaldehyde resin, are being evaluated for cesium removal and cesium

  11. Synthesis of high purity o-cresol novolac epoxy resins

    Microsoft Academic Search

    Xiao-Wei Tian; Zhen-Guo Yang; Jiang-yan Sun; Zheng Ji

    2008-01-01

    O-cresol novolac epoxy resins are used widely as electronic encapsulating materials. When the pitch wires in electronic systems are more slender, there are pressing demands for high purity o-cresol novolac epoxy resin which are with little content of hydrolyzable chloride. In this paper, o-cresol novolac resin was synthesized from para-formaldehyde and o-cresol in the presence of a mixed catalyst (oxalic

  12. Impact-modified epoxy resin with glassy second component

    Microsoft Academic Search

    Sung C. Kim; Hugh R. Brown

    1987-01-01

    A resorcinol-based epoxy resin was modified by incorporating a glassy second component. The mixture showed a heterogeneous morphology with two clearly defined phases, one phase rich in oligomer, the other phase composed mainly of resorcinol epoxy resin. The fracture toughness measured asG1c andK1c values showed an increase from 174J m-2 and 0.89 MN m-1.5 S in pure epoxy resin to

  13. Calcium isotope fractionation in liquid chromatography with crown ether resins

    Microsoft Academic Search

    Shigeki Nemoto; Kojiro Suga; Yuji Fukuda; Masao Nomura; Tatsuya Suzuki; Takao Oi

    2012-01-01

    Breakthrough mode liquid chromatography was employed to study calcium isotope fractionation. Highly porous silica beads, the inner pores of which were embedded with a benzo-18-crown-6 ether resin or a benzo-15-crown-5 ether resin, were used as column packing material. For both the resins, enrichment of heavier isotopes of calcium was observed in the frontal part of their respective calcium chromatograms. The

  14. Radiation-thickening of iso-polyester resin

    NASA Astrophysics Data System (ADS)

    Czayka, M.; Fisch, M.; Uribe, Roberto M.; Vargas–Aburto, C.

    2007-06-01

    A novel method to thicken iso-polyester resins using high-energy electrons is presented along with data characterizing the physical, structural, and thermal properties of the gelled-resin using compressive testing, DSC and IR spectroscopy. Additional data are presented on the tensile properties of a cured composite, made from a radiation-thickened molding compound, compared to traditional chemically thickened compound using the same base resin.

  15. Hydrolyzable polyester resins, varnishes and coating compositions containing the same

    DOEpatents

    Yamamori, Naoki (Minoo, JP); Yokoi, Junji (Nara, JP); Yoshikawa, Motoyoshi (Nara, JP)

    1984-01-01

    Preparation of hydrolyzable polyester resin comprising reacting polycarboxylic acid and polyhydric alcohol components, which is characterized by using, as at least part of said polyhydric alcohol component, a metallic salt of hydroxy carboxylic acid of the formula defined and effecting the polycondensation at a temperature which is no more than the decomposition temperature of said metallic salt. The polyester resins are useful as resinous vehicle of varnishes and antifouling paints.

  16. Diversity matters: how bees benefit from different resin sources.

    PubMed

    Drescher, Nora; Wallace, Helen M; Katouli, Mohammad; Massaro, Carmelina F; Leonhardt, Sara Diana

    2014-12-01

    Biodiverse environments provide a variety of resources that can be exploited by consumers. While many studies revealed a positive correlation between biodiversity and consumer biomass and richness, only few studies have investigated how resource diversity affects single consumers. To better understand whether a single consumer species benefits from diverse resources, we tested how the protective function of a defensive plant resource (i.e. resin exploited by social bees) varied among different sources and target organisms (predators, parasites and pathogens). To assess synergistic effects, resins from different plant genera were tested separately and in combination. We found that resin diversity is beneficial for bees, with its functional properties depending on the target organisms, type and composition of resin. Different resins showed different effects, and mixtures were more effective than some of the single resins (functional complementarity). We conclude that resins of different plant species target different organisms and act synergistically where combined. Bees that rely on resin for protection benefit more when they have access to diverse resin sources. Loss of biodiversity may in turn destabilize consumer populations due to restricted access to a variety of resources. PMID:25205030

  17. Maleimido substituted cyclotriphosphazene resins for fire and heat resistant composites

    NASA Technical Reports Server (NTRS)

    Kumar, D.; Fohlen, G. M.; Parker, J. A.

    1983-01-01

    A new class of fire- and heat-resistant matrix resins have been synthesized by the thermal polymerization of maleimido substituted phenoxycyclotriphosphazenes. The resins have exhibited a char yield of 82 percent at 800 C in nitrogen and 81 percent at 700 C in air. Graphite-fabric laminates based on a resin of this class have shown a limiting oxygen index of 100 percent even at 300 C. Details of the fabrication of the resins and the composites and testing procedures are discussed.

  18. Oil recovery method utilizing highly oxyalklated phenolic resins

    SciTech Connect

    Blair, C.M. Jr.; Stout, C.A.; Olsen, R.P.

    1989-03-21

    A method is described for recovering petroleum from a subterranean reservoir. It consists of introducing, through an injection well, a predeterminable amount of polyalkylene oxide adduct of a fusible phenolic, hydrocarbon-soluble synthetic resin, the resin containing from about 4 to about 16 phenolic groups and being a condensate of an ortho or para alkyl or cycloaliphatic substituted phenol and an aldehyde. The adduct is formed by further condensation of the condensate resin with ethylene oxide and at least one other alkylene oxide containing 3 or 4 carbon atoms. The adduct contains more than about 1% by weight and less than about 50% by weight of phenolic resin moiety.

  19. Acetylene-chromene terminated resins as high temperature thermosets

    NASA Technical Reports Server (NTRS)

    Godschalx, J. P.; Inbasekaran, M. N.; Bartos, B. R.; Scheck, D. M.; Laman, S. A.

    1990-01-01

    A novel phase transfer catalyzed process for the preparation of propargyl ethers has been developed. The propargyl ethers serve as precursors to a new class of thermosetting resins called acetylene-chromene terminated (ACT) resins. Heat treatment of a solution of propargyl ethers with various catalysts, followed by removal of solvent leads to the ACT resins via partial conversion of the propargyl ether groups to chromenes. This process reduces the energy content of the resin systems and reduces the amount of shrinkage found during cure. Due to the presence of the solvent the process is safe and gives rise to low viscosity products suitable for resin transfer molding and filament winding type applications. Due to the high glass transition temperature, high modulus, and low moisture uptake the cured resins display better than 232 C/wet performance. The thermal stability of the ACT resins in air at 204 C is superior to that of conventional bismaleimide resins. The resins also display excellent electrical properties.

  20. Analysis of residual stress in the resin of metal-resin adhesion structures by scanning acoustic microscopy.

    PubMed

    Ohno, Hiroki; Endo, Kazuhiko; Nagano-Takebe, Futami; Ida, Yusuke; Kakino, Ken; Narita, Toshio

    2013-11-30

    The residual stress caused by polymerization shrinkage and thermal contraction of a heat-curing resin containing 4-META on a metal-resin structure was measured by a scanning acoustic microscope. The tensile residual stress in the resin occurred within 70 µm of the adhesion interface with a flat plate specimen. The maximum tensile stress was about 58 MPa at the interface. On a metal plate specimen with retention holes, ring-like cracks in the resin occurred around the retention holes with the adhesive specimen and many linear cracks occurred in the resin vertical to the longitudinal direction of the metal frame with the non-adhesive specimens. There was tensile residual stress on the resin surface at the center of the retention holes of the adhesion specimen, indicating that the stress in the specimen with surface treatment for adhesion was higher than in that without surface treatment. PMID:24240901

  1. Organic geochemistry of resins from modern Agathis australis and Eocene resins from New Zealand: Diagenetic and taxonomic implications

    Microsoft Academic Search

    Paul C. Lyons; Maria Mastalerz; William H. Orem

    2009-01-01

    A maturation series of resins and fossil resins from New Zealand, ranging in age from Modern to Eocene and ranging from uncoalified to high volatile C bituminous coal, were analyzed by elemental, pyrolysis-gas chromatography (Py-GC), Fourier Transform infrared (FTir), and solid-state 13C nuclear magnetic resonance (13C NMR) techniques. For comparison, four resin samples from the Latrobe Valley, Australia, were analyzed.

  2. Epoxy Resins from fats. III. preparation and properties of resins from blends of a commercial diglycidyl ether and epoxidized glycerides cured with phthalic anhydride

    Microsoft Academic Search

    Leonard L. Gelb; Waldo C. Ault; William E. Palm; Lee P. Witnauer; William S. Port

    1960-01-01

    ATTY DERIVATIVES are playing an ever-increasing role in the modification of resins and plastics. Modifiers for epoxy resins have been sought for various specific purposes, such as to improve flexibility of the resin, to reduce the viscosity of the working mixture, to increase the pot life of the preeured mixture, and to fill the resin and thereby simultaneously improve dimensional

  3. 76 FR 28455 - Granular Polytetrafluoroethylene Resin From Italy; Scheduling of an Expedited Five-Year Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-17

    ...Granular Polytetrafluoroethylene Resin From Italy; Scheduling of an Expedited Five-Year...Granular Polytetrafluoroethylene Resin From Italy AGENCY: United States International Trade...granular polytetrafluoroethylene resin from Italy would be likely to lead to...

  4. 76 FR 27663 - Granular Polytetrafluoroethylene Resin From Italy; Scheduling of an Expedited Five-Year Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ...Granular Polytetrafluoroethylene Resin From Italy; Scheduling of an Expedited Five-Year...Granular Polytetrafluoroethylene Resin From Italy AGENCY: United States International Trade...granular polytetrafluoroethylene resin from Italy would be likely to lead to...

  5. 40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Mixed alkyl phenolic novolak resin (generic). 721.5380...721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical...generically as mixed alkyl phenolic novolak resin (PMN P-98-718)...

  6. 40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Mixed alkyl phenolic novolak resin (generic). 721.5380...721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical...generically as mixed alkyl phenolic novolak resin (PMN P-98-718)...

  7. 40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Mixed alkyl phenolic novolak resin (generic). 721.5380...721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical...generically as mixed alkyl phenolic novolak resin (PMN P-98-718)...

  8. 40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Mixed alkyl phenolic novolak resin (generic). 721.5380...721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical...generically as mixed alkyl phenolic novolak resin (PMN P-98-718)...

  9. Improved epoxy resin for constructing cryogenic filament-wound pressure vessels

    NASA Technical Reports Server (NTRS)

    Molho, R.; Soffer, L. M.

    1971-01-01

    Mechanical properties of new resin at cryogenic temperatures are substantially improved over similar composite structures utilizing conventional resins, while properties at ambient temperature are identical to conventional resin composites.

  10. 40 CFR 721.5380 - Mixed alkyl phenolic novolak resin (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Mixed alkyl phenolic novolak resin (generic). 721.5380...721.5380 Mixed alkyl phenolic novolak resin (generic). (a) Chemical...generically as mixed alkyl phenolic novolak resin (PMN P-98-718)...

  11. 21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 false Bracket adhesive resin and tooth conditioner. 872...Prosthetic Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a...

  12. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Paint, paint-related material, adhesives, ink and resins. 173.173 Section... Paint, paint-related material, adhesives, ink and resins. (a) When the...Paint, paint-related material, adhesives, ink and resins must be packaged...

  13. 21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 false Bracket adhesive resin and tooth conditioner. 872...Prosthetic Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a...

  14. 21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 false Bracket adhesive resin and tooth conditioner. 872...Prosthetic Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a...

  15. Conversion of ion exchange resin to various functional resins and the application in the field of pharmaceutical sciences

    NASA Astrophysics Data System (ADS)

    Nakayama, Morio

    Ion exchange resins are widely used for separating ions in the solution, desalination, removal of impurities, and etc. Giving a new function to these ion exchange resins enables the application in more various fields. Until now, we carried out the research work about the following 5 project.: (1) Conversion of ion exchange resins into selective adsorbents by using low molecular reagents, which possess capabilities of a selective reaction with target ions, ion exchange reaction with the ion exchange resin and strong physical adsorption to the ion exchange resin. (2) Synthesis of resins for ion exchange high performance liquid chromatography (IEHPLC) and the analysis of biomaterials. (3) Development of insoluble macromolecular Sn(II) complex based on the aminophosphonic acid type ion exchange resin and its application to the 99mTc labeling of proteins. (4) Development of a new 68Ge-68Ga generator using N-methylglucamine type organic polymer as the adsorbent for 68Ge and production of 68Ga for PET. (5) Preparation of an ion-exchangeable polymer bead wrapped with bilayer membrane structures. In this paper, the application of various functional resins prepared based on ion exchange resin in the field of pharmaceutical sciences has been summarized.

  16. Characterization of Composite Fan Case Resins

    NASA Technical Reports Server (NTRS)

    Dvoracek, Charlene M.

    2004-01-01

    The majority of commercial turbine engines that power today s aircraft use a large fan driven by the engine core to generate thrust which dramatically increases the engine s efficiency. However, if one of these fan blades fails during flight, it becomes high energy shrapnel, potentially impacting the engine or puncturing the aircraft itself and thus risking the lives of passengers. To solve this problem, the fan case must be capable of containing a fan blade should it break off during flight. Currently, all commercial fan cases are made of either just a thick metal barrier or a thinner metal wall surrounded by Kevlar-an ultra strong fiber that elastically catches the blade. My summer 2004 project was to characterize the resins for a composite fan case that will be lighter and more efficient than the current metal. The composite fan case is created by braiding carbon fibers and injecting a polymer resin into the braid. The resin holds the fibers together, so at first using the strongest polymer appears to logically lead to the strongest fan case. Unfortunately, the stronger polymers are too viscous when melted. This makes the manufacturing process more difficult because the polymer does not flow as freely through the braid, and the final product is less dense. With all of this in mind, it is important to remember that the strength of the polymer is still imperative; the case must still contain blades with high impact energy. The research identified which polymer had the right balance of properties, including ease of fabrication, toughness, and ability to transfer the load to the carbon fibers. Resin deformation was studied to better understand the composite response during high speed impact. My role in this research was the testing of polymers using dynamic mechanical analysis and tensile, compression, and torsion testing. Dynamic mechanical analysis examines the response of materials under cyclic loading. Two techniques were used for dynamic mechanical analysis. The ARES Instrument analyzed the material through torsion. The second machine, TA Instruments apparatus, applied a bending force to the specimen. These experiments were used to explore the effects of temperature and strain rate on the stiffness and strength of the resins. The two different types of loading allowed us to verify our results. An axial-torsional load frame, manufactured by MTS Systems, Inc., was used to conduct the tensile, compression, and torsional testing. These tests were used to determine the stress-strain curves for the resins. The elastic and plastic deformation data was provided to another team member for characterization of high fidelity material property predictions. This information was useful in having a better understanding of the polymers so that the fan cases could be as sturdy as possible. Deformation studies are the foundation for the computational modeling that provides the structural design of a composite engine case as well as detailed analysis of the blade impact event.

  17. HIGH ASPECT RATIO ION EXCHANGE RESIN BED - HYDRAULIC RESULTS FOR SPERICAL RESIN BEADS

    SciTech Connect

    Duignan, M; Charles Nash, C; Timothy Punch, T

    2007-09-27

    A principal role of the DOE Savannah River Site is to safely dispose of a large volume of liquid nuclear waste held in many storage tanks. An in-tank ion exchange unit is being considered for cesium removal to accelerate waste processing. This unit is planned to have a relatively high bed height to diameter ratio (10:1). Complicating the design is the need to cool the ion exchange media; therefore, the ion exchange column will have a central cooling core making the flow path annular. To separate cesium from waste the media being considered is made of resorcinol formaldehyde resin deposited on spherical plastic beads and is a substitute for a previously tested resin made of crystalline silicotitanate. This spherical media not only has an advantage of being mechanically robust, but, unlike its predecessor, it is also reusable, that is, loaded cesium can be removed through elution and regeneration. Resin regeneration leads to more efficient operation and less spent resin waste, but its hydraulic performance in the planned ion exchange column was unknown. Moreover, the recycling process of this spherical resorcinol formaldehyde causes its volume to significantly shrink and swell. To determine the spherical media's hydraulic demand a linearly scaled column was designed and tested. The waste simulant used was prototypic of the wastes' viscosity and density. This paper discusses the hydraulic performance of the media that will be used to assist in the design of a full-scale unit.

  18. Modification of epoxy resin with siloxane containing phenol aralkyl epoxy resin for electronic encapsulation application

    Microsoft Academic Search

    Tsung-Han Ho; Chun-Shan Wang

    2001-01-01

    A process was developed to incorporate stable dispersed polysiloxane particles into a phenol aralkyl novolac epoxy resin, which was used as an ingredient in the encapsulant formulation to withstand the thermal stress. The mechanical and dynamic viscoelastic properties and morphologies of rubber-modified epoxy networks were studied. A “sea-island” structure (“islands” of silicone rubber dispersed in the “sea” of an epoxy

  19. Comparison of chromatographic ion-exchange resins VI. Weak anion-exchange resins.

    PubMed

    Staby, Arne; Jensen, Randi Holm; Bensch, Matthias; Hubbuch, Jürgen; Dünweber, Dorte L; Krarup, Janus; Nielsen, Jacob; Lund, Mette; Kidal, Steffen; Hansen, Thomas Budde; Jensen, Inge Holm

    2007-09-14

    A comparative study on weak anion exchangers was performed to investigate the pH dependence, binding strength, particle size distribution, and static and dynamic capacity of the chromatographic resins. The resins tested included: DEAE Sepharose FF, Poros 50 D, Fractogel EMD DEAE (M), MacroPrep DEAE Support, DEAE Ceramic HyperD 20, and Toyopearl DEAE 650 M. Testing was performed with five different model proteins: Anti-FVII mAb (immunoglobulin G), aprotinin, bovine serum albumin (BSA), Lipolase (Novozymes), and myoglobin. Retention showed an expected increasing trend as a function of pH for proteins with low pI. A decrease in retention was observed for some resins at pH 9 likely due to initiation of deprotonation of the weak anion-exchange ligands. Expected particle size distribution was obtained for all resins compared to previous studies. Binding strength to weak anion-exchange resins as a function of ionic strength depends on the specific protein. Binding and elution at low salt concentration may be performed with Toyopearl DEAE 650 M, while binding and elution at high salt concentration may be performed with MacroPrep DEAE Support. Highest binding capacities were generally obtained with Poros 50 D followed by DEAE Ceramic HyperD 20. A general good agreement was obtained between this study and data obtained by the suppliers. Verification of binding strength trends with model proteins was achieved with human growth hormone (hGH) and a hGH variant on the same resins with different elution salts, sodium chloride, sodium hydrogenphosphate, sodium sulphate, and sodium acetate. Static capacity measurements obtained in the traditional experimental set-up were compared with high-throughput screening (HTS) technique experiments with reasonable agreement. Isotherm data obtained from HTS techniques and pulse experiments were successfully combined with mathematical modelling to simulate, develop and optimise the separation process of two model proteins, Lipolase and BSA. The data presented in this paper may be used for selection of resins for testing in process development. PMID:17658538

  20. Isothermal aging effects on PMR-15 resin

    NASA Technical Reports Server (NTRS)

    Bowles, Kenneth J.; Jayne, Douglas; Leonhardt, Todd A.

    1992-01-01

    Specimens of PMR-15 polyimide neat resin were aged in air at temperatures of 288, 316, and 343 C. Weight losses and dimensional changes were monitored during the course of the exposure time. Physical changes were also observed by optical and electron microscopy. It was found that polyimide polymer degradation occurred within a thin surface layer that developed and grew during thermal aging. The cores of the polymer specimens were protected from oxidative degradation, and they were relatively unchanged by the thermal treatment. Surface cracking was observed at 343 C and was probably due to an interaction between voids and stresses that developed in the surface layer.

  1. Resin catalysts and method of preparation

    DOEpatents

    Smith, L.A. Jr.

    1986-12-16

    Heat stabilized catalyst compositions are prepared from nuclear sulfonic acid, for example, macroporous crosslinked polyvinyl aromatic compounds containing sulfonic acid groups are neutralized with a metal of Al, Fe, Zn, Cu, Ni, ions or mixtures and alkali, alkaline earth metals or ammonium ions by contacting the resin containing the sulfonic acid with aqueous solutions of the metals salts and alkali, alkaline earth metal or ammonium salts. The catalysts have at least 50% of the sulfonic acid groups neutralized with metal ions and the balance of the sulfonic acid groups neutralized with alkali, alkaline earth ions or ammonium ions.

  2. Electroactive polymer gels based on epoxy resin

    NASA Astrophysics Data System (ADS)

    Samui, A. B.; Jayakumar, S.; Jayalakshmi, C. G.; Pandey, K.; Sivaraman, P.

    2007-04-01

    Five types of epoxy gels have been synthesized from common epoxy resins and hardeners. Fumed silica and nanoclay, respectively, were used as fillers and butyl methacrylate/acrylamide were used as monomer(s) for making interpenetrating polymer networks (IPNs) in three compositions. Swelling study, tensile property evaluation, dynamic mechanical thermal analysis, thermo-gravimetric analysis, scanning electron microscopy and electroactive property evaluation were done. The gels have sufficient mechanical strength and the time taken for bending to 20° was found to be 22 min for forward bias whereas it was just 12 min for reverse bias.

  3. Isothermal aging effects on PMR-15 resin

    NASA Technical Reports Server (NTRS)

    Bowles, Kenneth J.; Jayne, Douglas; Leonhardt, Todd A.

    1993-01-01

    Specimens of PMR-15 polyimide neat resin were aged in air at temperatures of 288, 316, and 343 C. Weight losses and dimensional changes were monitored during the course of the exposure time. Physical changes were also observed by optical and electron microscopy. It was found that polyimide polymer degradation occurred within a thin surface layer that developed and grew during thermal aging. The cores of the polymer specimens were protected from oxidative degradation, and they were relatively unchanged by the thermal treatment. Surface cracking was observed at 343 C and was probably due to an interaction between voids and stresses that developed in the surface layer.

  4. 40 CFR 721.9480 - Resorcinol, formaldehyde substituted carbomonocycle resin (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Resorcinol, formaldehyde substituted carbomonocycle resin...Substances § 721.9480 Resorcinol, formaldehyde substituted carbomonocycle resin...identified generically as resorcinol, formaldehyde substituted carbomonocycle...

  5. The effect of resin thickness on polymerization characteristics of silorane-based composite resin

    PubMed Central

    Son, Sung-Ae; Roh, Hyoung-Mee; Hur, Bock; Kwon, Yong-Hoon

    2014-01-01

    Objectives This study examined the influence of the resin thickness on the polymerization of silorane- and methacrylate-based composites. Materials and Methods One silorane-based (Filtek P90, 3M ESPE) and two methacrylate-based (Filtek Z250 and Z350, 3M ESPE) composite resins were used. The number of photons were detected using a photodiode detector at the different thicknesses (thickness, 1, 2 and 3 mm) specimens. The microhardness of the top and bottom surfaces was measured (n = 15) using a Vickers hardness with 200 gf load and 15 sec dwell time conditions. The degree of conversion (DC) of the specimens was determined using Fourier transform infrared spectroscopy (FTIR). Scratched powder of each top and bottom surface of the specimen dissolved in ethanol for transmission FTIR spectroscopy. The refractive index was measured using a Abbe-type refractometer. To measure the polymerization shrinkage, a linometer was used. The results were analyzed using two-way ANOVA and Tukey's test at p < 0.05 level. Results The silorane-based resin composite showed the lowest filler content and light attenuation among the specimens. P90 showed the highest values in the DC and the lowest microhardness at all depth. In the polymerization shrinkage, P90 showed a significantly lower shrinkage than the rest two resin products (p < 0.05). P90 showed a significantly lower refractive index than the remaining two resin products (p < 0.05). Conclusions DC, microhardness, polymerization rate and refractive index linearly decreased as specimen thickness linearly increased. P90 showed much less polymerization shrinkage compared to other specimens. P90, even though achieved the highest DC, showed the lowest microhardness and refractive index. PMID:25383351

  6. Organic geochemistry of resins from modern Agathis australis and Eocene resins from New Zealand: Diagenetic and taxonomic implications

    USGS Publications Warehouse

    Lyons, P.C.; Mastalerz, Maria; Orem, W.H.

    2009-01-01

    A maturation series of resins and fossil resins from New Zealand, ranging in age from Modern to Eocene and ranging from uncoalified to high volatile C bituminous coal, were analyzed by elemental, pyrolysis-gas chromatography (Py-GC), Fourier Transform infrared (FTir), and solid-state 13C nuclear magnetic resonance (13C NMR) techniques. For comparison, four resin samples from the Latrobe Valley, Australia, were analyzed. All of the resins and fossil resins of this study show very high H/C atomic ratios, and are characterized by dominant peaks in the 10-60??ppm range of solid-state 13C NMR spectra and prominent bands in the aliphatic stretching region (2800-3000??cm- 1) of FTir spectra, all indicating a highly aliphatic molecular structure. The 13C NMR and FTir data indicate a diterpenoid structure for these resins. There is an abrupt loss of oxygen that occurs at the Lignite A/Subbituminous C stage, which is attributed to a dramatic loss of carboxyl (COOH) from the diterpenoid molecule. This is a new finding in the diagenesis of resins. This important loss in oxygenated functional groups is attributed to a maturation change. Also, there is a progressive loss of exomethylene (CH2) groups with increasing degree of maturation, as shown by both 13C NMR and FTir data. This change has been noted by previous investigators. Exomethylene is absent in the fossil resins from the Eocene high volatile C bituminous coals. This progressive loss is characteristic of Class I resinites. FTir data indicate that the oxygenated functional groups are strong in all the resin samples except the fossil resin from high volatile C bituminous coal. This important change in oxygenated functional groups is attributed to maturation changes. The 13C NMR and FTir data indicate there are minor changes in the Agathis australis resin from the living tree and soil, which suggests that alteration of A. australis resins begins shortly after deposition in the soil for as little as 1000??years. The Morwell and Yallourn fossil resins from brown coal (lignite B) Australia do not have some of the FTir characteristics of the New Zealand resins, which most likely indicates they have a different plant source because different degrees of oxidation and weathering and changes due to fires (i.e., charring) can be ruled out. Our results have implications for studies of the maturation, provenance, and botanical sources of fossil resins and resinites in Eocene and Miocene coals and sediments of New Zealand and Australia. ?? 2009 Elsevier B.V. All rights reserved.

  7. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...the weight of the calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by weight of titanium dioxide as an optional adjuvant substance. (c) The mineral reinforced nylon resins with or without the optional...

  8. Tribological Properties of Blends of Melamine-Formaldehyde Resin With

    E-print Network

    North Texas, University of

    Tribological Properties of Blends of Melamine-Formaldehyde Resin With Low Density Polyethylene Texas, Denton, Texas 76203-5310 Tribological properties of blends of melamine-formalde- hyde resin (MFR tribology. Blending can be used to improve tribological properties of LDPE. POLYM. ENG. SCI., 48

  9. Modification of polyester resin based composites induced by seawater absorption

    Microsoft Academic Search

    A. M. Visco; L. Calabrese; P. Cianciafara

    2008-01-01

    This research is a study on seawater absorption ability and on mechanical performance (before and after immersion in seawater) of two composites that basically differ for what concerns the polyester resin (isophthalic or orthophthalic) employed in boats manufacture. Experimental tests, carried out on the two resins, evidenced that they differ for what concerns their structural organization, water diffusion coefficient, thermal

  10. Resin Infusion under Flexible Tooling (RIFT): a review

    Microsoft Academic Search

    Christopher Williams; John Summerscales; Stephen Grove

    1996-01-01

    Increasing legislation to limit styrene emissions (mainly from polyester resin systems) into the work place has been the key factor in promoting new technology in the manufacture of fibre reinforced plastics composites. Styrene emissions can be reduced by the development of: resin systems with low styrene emission; improved ventilation and air filtering systems; closed moulding techniques. It is the final

  11. Resin Infiltration into Differentially Extended Experimental Carious Lesions

    PubMed Central

    Arnold, Wolfgang H; Bachstaedter, Lena; Benz, Korbinian; Naumova, Ella A

    2014-01-01

    Resin infiltration of initial caries lesions is a novel method of caries therapy. However, it has some limitations. Therefore, further experimental studies are needed to improve resin infiltration. It was the aim of this investigation to study resin infiltra-tion into different experimental carious lesions. Caries-free extracted human molars and premolars were demineralized for 3, 6, 9 and 12 days and infiltrated with resin. Prior to infiltration, the teeth were incubated with sodium fluorescein. After em-bedding, serial sections were cut through the experimental lesions, and the penetration of the resin was measured with fluo-rescence microscopy. Two infiltrated teeth from each time interval were not embedded and cut. Infiltration of the resin was then studied with EDS element analysis. The results showed that with increasing demineralization time, the lesion expansion was also increasing, and the resin infiltration was always almost complete. From these results it can be concluded that artifi-cial standardized caries-like lesions are suitable for experimental studies of resin infiltration. PMID:26019729

  12. Controlled drug release from coated floating ion exchange resin beads

    Microsoft Academic Search

    F. Atyabi; H. L. Sharma; H. A. H. Mohammad; J. T. Fell

    1996-01-01

    Ion exchange resin beads can be loaded with bicarbonate and coated with a semipermeable membrane. These beads exhibit prolonged gastric residence due to release of carbon dioxide which is trapped inside the coating of the beads. In addition to the bicarbonate, a model drug, theophylline, has also been loaded onto the resin. This system gives a controlled release of drug,

  13. Original article Variation in the position of resin canals

    E-print Network

    Paris-Sud XI, Université de

    the crown; and b), trees with marginal resin canals in the lower part of the crown followed in the rest of their crown. The frequency of the 2 types of tree varies between species and hybrids and also and provenances, 2 types of adult tree were dis- tinguished: a) trees with marginal resin canals throughout

  14. A Water-Dilutable Furan Resin Binder for Particleboard

    Microsoft Academic Search

    Robert H. Leitheiser; Ben R. Bogner; Frank C. Grant-Acquah; William E. Johns; Walter Plagemann

    1982-01-01

    A water-dilutable furan resin made from agricultural residues can be used as a binder for particleboard. Board properties obtained were comparable to those obtained with commercial phenolic binders. Board costs can be significantly reduced by using low cost ammonium lignin sulfonate as a resin extender.

  15. Stress Transfer in Single Fiber\\/ Resin Tensile Tests

    Microsoft Academic Search

    W. D. Bascom; R. M. Jensen

    1986-01-01

    Microscale (25 mm gauge length) “dogbone” resin specimens with single carbon fibers embedded through the length of the specimen have been studied as a method for determining the fiber-resin interphase strength. The specimens are pulled in tension until the fiber fragments to a critical length, lc. Evidence is presented here, based primarily on the relaxation of stress birefringence around the

  16. Regional Measurement of Resin-Dentin Bonding as an Array

    Microsoft Academic Search

    Y. Shono; T. Ogawa; M. Terashita; R. M. Carvalho; E. L. Pashley; D. H. Pashley

    1999-01-01

    During the development of the microtensile bond-testing method, large variations in bond strengths were noted among serial sections. The reason for these variations is unknown. The purpose of this work was to determine the consistency of resin-dentin bond strengths across the occlusal surface of coronal dentin by dividing composite resin buildups into an array of 1 x 1 mm beams,

  17. New flexibilized diallyl phthalate resins for encapsulating electronic display devices

    Microsoft Academic Search

    A. M. Usmani; I. O. Salyer

    1981-01-01

    This research investigated diallyl phthalate encapsulating resins as a replacement for the moisture sensitive epoxies now used in light emitting diode (LED) displays. Consideration of display resin requirements led us to select for study the diallyl phthalate (DAP) polymer thermosetting system, which had most of the performance properties desired, but was excessively brittle. Flexibilizing co-monomers were evaluated including both vinyl

  18. SWELLING OF A CHELATING MACROPOROUS RESIN DURING METAL ION EXCHANGE

    Microsoft Academic Search

    F. Mijangos; M. Ortueta; I. Aguirre

    2000-01-01

    The kinetics of heavy metal ion exchange onto a commercial chelating resin was investigated from the standpoint of the swelling-shrinking experienced by the resin bead during the overall ion exchange process. Temporal measurements of the volume variations were carried out for every step of an operational cycle, metal load, elution and regeneration of the ion exchanger, using a microreactor mainly

  19. Chemical degradation of an ion exchange resin processing salt solutions

    Microsoft Academic Search

    Stuart T. Arm; David L. Blanchard; Sandra K. Fiskum

    2005-01-01

    This paper describes the results from an investigation into the chemical degradation of an organic ion exchange resin, SuperLig® 644, over 25 repeated cycles separating cesium from an alkaline solution of sodium salts with subsequent elution. Battelle Pacific Northwest Division (PNWD) tested the resin with a salt solution simulating the radioactive wastes currently stored at Hanford, Washington, USA generated from

  20. MODELING RESULTS FROM CESIUM ION EXCHANGE PROCESSING WITH SPHERICAL RESINS

    Microsoft Academic Search

    C. Nash; T. Hang; S. Aleman

    2011-01-01

    Ion exchange modeling was conducted at the Savannah River National Laboratory to compare the performance of two organic resins in support of Small Column Ion Exchange (SCIX). In-tank ion exchange (IX) columns are being considered for cesium removal at Hanford and the Savannah River Site (SRS). The spherical forms of resorcinol formaldehyde ion exchange resin (sRF) as well as a

  1. Electrolytic desorption of silver from ion-exchange resins

    Microsoft Academic Search

    Slavica Pavlini?; Ivan Piljac

    1998-01-01

    Strong base ion-exchange resins Lewatit M 500 and Lewatit M 504 have steep ascending parts of isotherm curves in the range of low silver concentration in solution and can be used for silver extraction from plating rinsing effluents. Common elution methods are very inefficient for silver removal from strong base ion-exchange resins. Hence, the silver regeneration was performed by the

  2. The absorption of mould release agent by epoxy resin

    Microsoft Academic Search

    A. J Shields; D. M Hepburn; I. J Kemp; J. M Cooper

    2000-01-01

    A wide range of polymeric materials, including epoxy resins, are moulded to produce components for various uses. Silicon-based release agents are commonly used to ensure that the component can be released from the mould. This work demonstrates that the release agent is absorbed by resin during casting. The reaction of samples to various stress regimes, i.e. chemical, mechanical, radiative and

  3. The curing classifier of dielectrics based on epoxy resins

    Microsoft Academic Search

    V. Mentlik; J. Pihera; R. Polansky; P. Prosr; P. Trnka

    2006-01-01

    Monitoring of the properties and applicability of high-voltage insulating systems containing epoxy resins require knowledge of curing degree of these resins. This curing degree is considered to be the key parameter for quality of materials used for these systems. Application of differential thermal analysis (DTA) for evaluation of curing degree of three-component composite materials (glass fabric, reconstructed mica, and epoxy

  4. Chemical recycling of phenol resin by supercritical methanol

    Microsoft Academic Search

    Jun-ichi Ozaki; Subagijo Kastria Ingwang Djaja; Asao Oya

    2000-01-01

    Thermosetting resin is one of the most difficult substances to be recycled, because it includes a highly cross-linked structure which gives the polymer chemical and thermal resistances. A preliminary study on the technique to recycle phenol resin was conducted in the present study, which was intended to be achieved by the use of a supercritical fluid. Supercritical methanol was employed

  5. Thermal degradation of phenolic resin\\/silica hybrid ceramers

    Microsoft Academic Search

    Jia-Min Lin; Chen-Chi M. Ma

    2000-01-01

    The kinetic parameters and the structural change of thermal degradation of phenolic resin\\/silica hybrid ceramers with different mixing ratios were investigated. The activation energies of thermal degradation were calculated by the methods of Kissinger, Friedman and Ozawa from a conventional dynamic thermogravimetric measurement in nitrogen atmosphere at several different heating rates. Both pure phenolic resin and hybrid ceramers show two

  6. Controlled Alloying of CSM Roofing Membranes with Thermoplastic Resins

    Microsoft Academic Search

    Jimmie L. Stanton

    1996-01-01

    Single-ply roofing membranes based on CSM have been effective in commercial installation for over twenty years. Selective blending of thermoplastic resins, CPE (CM) and EVA, into a standard CSM formulation have been performed to evaluate the effect on calendering, accelerated aging and seaming ability. The effect of these resins on other physical properties are also characterized. Further, care must also

  7. ISOLATION OF ORGANIC WATER POLLUTANTS BY XAD RESINS AND CARBON

    EPA Science Inventory

    The recovery efficiencies of XAD resins -2, -4, -7, and -8 and of resin mixtures were measured using distilled water samples containing 13 organic pollutants. An equal-weight mixture of XAD-4 and XAD-8 was most efficient. XAD-2 and XAD-4/8 were further tested and found effective ...

  8. SECURING CONTAINERIZED HAZARDOUS WASTES WITH POLYETHYLENE RESIN AND FIBERGLASS ENCAPSULATES

    EPA Science Inventory

    This study investigates the fabrication and use of polyethylene resin and fiberglass to encapsulate and secure containerized hazardous wastes. Laboratory-scale encapsulates of composite structure were made from powdered, high-density polyethylene (HDPE) and epoxy-resin-wetted fib...

  9. Resin collection and social immunity in honey bees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We determined if the use of resins, complex plant secretions with diverse antimicrobial properties, acts as a colony-level immune defense by honey bees. Colonies were enriched with extracts of Brazilian or Minnesotan propolis (a bee mixture of resins and wax) or were left as controls. We measured ge...

  10. Crystallization of isotactic polypropylene\\/natural terpene resins blends

    Microsoft Academic Search

    C Silvestre; S Cimmino; E D'Alma; M. L Di Lorenzo; E Di Pace

    1999-01-01

    The influence of two natural terpene resins on the morphology, phase structure and isothermal crystallization process of iPP was investigated by optical (OM) and electron microscopy (SEM) and differential scanning calorimetry (DSC). It was found that in dependence on temperature, composition and chemical nature of the resin, one, two or three phases can be present. The isothermal spherulite growth rate

  11. Analysis of the edge effect in resin transfer molding

    Microsoft Academic Search

    Wen-Bin Young; Chyi-Lang Lai

    1997-01-01

    In the process of resin transfer molding, small clearances may exist between the fiber preform and the mold edges because of loose edge fiber bundles, ill fitting size, or deformation of the fiber preform. The clearance results in a preferential resin flow path during the mold filling stage. This edge flow may disrupt the flow pattern and cause incomplete wetting

  12. Porosity reduction using optimized flow velocity in Resin Transfer Molding

    Microsoft Academic Search

    Jean Sébastien Leclerc; Edu Ruiz

    2008-01-01

    Liquid Composite Molding (LCM) regroups a number of well known manufacturing techniques of polymer composites based on resin injection through fibrous reinforcements. LCM processes such as RTM (Resin Transfer Molding) have been increasingly used to manufacture parts for a wide range of industrial applications and were shown to be cost effective in the low to medium range of volume production.

  13. Simplified mold filling simulation in resin transfer molding

    Microsoft Academic Search

    Zhong Cai

    1992-01-01

    A simplified mold filling simulation is developed to estimate the process variables for resin transfer molding (RTM) of structural composite parts. This approach uses very limited calculations and needs only microcomputer facilities. Resin flow in RTM processes is considered to follow Darcy's law. Both Newtonian fluid and power-law fluid are studied. Mold sections are decomposed as a combination of simple

  14. Formation of microvoids during resin-transfer molding process

    Microsoft Academic Search

    Moon Koo Kang; Woo Il Lee; H. Thomas Hahn

    2000-01-01

    Voids in a composite part are deleterious because they degrade its strength and modulus. In resin-transfer molding (RTM), voids result mainly from inhomogeneous fiber architecture. Such inhomogeneity leads to non-uniform permeability of the fiber preform, which in turn causes the resin velocity to vary from point to point at a micro scale. The capillary pressure, which also prevails at this

  15. Numerical Analysis of Controlled Injection Strategies in Resin Transfer Molding

    Microsoft Academic Search

    Akbar Shojaei; S. Reza Ghaffarian; S. Mohammad-Hossien Karimian

    2003-01-01

    Minimization of mold filling time without losing the part quality is an important issue in the Resin Transfer Molding (RTM) process. Among the various methods to achieve this, resin injection through multiple injection gates has become a practical way. However, inappropriate injection methods lead to numerous air entrapments, high inlet pressure and fiber mat deformation. In this study, a processing

  16. PROPERTIES OF SOME TOUGHENED, RADIATION STABLE EPOXY RESINS

    SciTech Connect

    Zhang, H.; Huang, R. J.; Li, L. F. [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China); Evans, D. [Advanced Cryogenic Materials, Abingdon, Oxon (United Kingdom)

    2008-03-03

    Impregnating resins for use in fusion magnet technology are required to be radiation stable, have a long useable life together with some degree of toughness to minimise the risk of cracking during cool-down. Some multi-functional resins in combination with solid aromatic amines have, in the past, been shown to have lost little of their strength after a total absorbed dose of 200 MGy. Using resins that are known to be radiation stable with a liquid aromatic amine hardener, the effect of adding an aromatic epoxy resin as a reactive 'toughening agent,' to improve the toughness of otherwise brittle resins has been assessed. Boron free glass composites, using various amounts of added toughening agent were prepared by vacuum impregnation and a number of critical composite properties have been measured, at room temperature and at 77 K.

  17. Radiation degradation in EPICOR-2 ion exchange resins

    SciTech Connect

    McConnell, J.W. Jr.; Johnson, D.A.; Sanders, R.D. Sr.

    1990-09-01

    The Low-Level Waste Data base Development -- EPICOR-II Resin/Liner Investigation Program funded by the US Nuclear Regulatory Commission is investigating chemical and physical conditions for organic ion exchange resins contained in several EPICOR-II prefilters. Those prefilters were used during cleanup of contaminated water from the Three Mile Island Nuclear Power Station after the March 1979 accident. The work was performed by EG G Idaho, Inc. at the Idaho Engineering Laboratory. This is the final report of this task and summarizes results and analyses of three samplings of ion exchange resins from prefilters PF-8 and -20. Results are compared with baseline data from tests performed on unirradiated resins supplied by Epicor, Inc. to determine the extent of degradation due to the high internal radiation dose received by the organic resins. Results also are compared with those of other researchers. 18 refs., 23 figs., 7 tabs.

  18. Surface characteristics of resin composite materials after finishing and polishing.

    PubMed

    St Germain, Henry; Samuelson, Bart A

    2015-01-01

    This in vitro study determined the surface roughness (Ra) and absolute gloss (AG) values for 2 resin composites: a microhybrid and a microfill. Eight groups (n = 4) of each resin composite were prepared, along with 4 controls (Mylar strip) for the 2 resin composites. After finishing with a medium polishing disc, the specimens from each resin composite material were subjected to 7 polishing procedures, and Ra measurements and AG values were determined. Two-way ANOVA and Fisher's LSD multiple comparisons revealed significant differences (P ? 0.05). For both materials, the control group produced the lowest Ra values and highest AG values, and the medium polishing disc produced the highest Ra values and lowest AG values. Of the 2 resin composites, the microhybrid had lower mean Ra and higher mean AG than the microfill for the majority of the polishing procedures. Pearson's r correlation coefficient (P ? 0.001) indicated an inverse linear relationship between Ra and AG. PMID:25734283

  19. Stochastic Flow Modeling for Resin Transfer Moulding

    NASA Astrophysics Data System (ADS)

    Desplentere, Frederik; Verpoest, Ignaas; Lomov, Stepan

    2009-07-01

    Liquid moulding processes suffer from inherently present scatter in the textile reinforcement properties. This variability can lead to unwanted filling patterns within the mould resulting in bad parts. If thermoplastic resins are used with the in-situ polymerisation technique, an additional difficulty appears. The time window to inject the material is small if industrial processing parameters are used (<5 minutes). To model the stochastic nature of RTM, Darcy's description of the mould filling process has been used with the permeability distribution of the preform given as a random field. The random field of the permeability is constructed as a correlated field with an exponential correlation function. Optical microscopy and X-ray micro-CT have been used to study the stochastic parameters of the geometry for 2D and 3D woven textile preforms. The parameters describing the random permeability field (average, standard deviation and correlation length) are identified based on the stochastic parameters of the geometry for the preforms, analytical estimations and CFD modelling of the permeability. In order to implement the random field for the permeability and the variability for the resin viscosity, an add-on to the mould filling simulation software PAM-RTM™ has been developed. This analysis has been validated on case studies.

  20. Phosphorus-containing imide resins - Modification by elastomers

    NASA Technical Reports Server (NTRS)

    Varma, I. K.; Fohlen, G. M.; Parker, J. A.; Varma, D. S.

    1984-01-01

    The syntheses and general features of addition-type maleimide resins based on bis(m-aminophenyl)phosphine oxide and tris(m-aminophenyl)phosphine oxide have been reported previously. These resins have been used to fabricate graphite cloth laminates having excellent flame resistance. These composites did not burn even in pure oxygen. However, these resins were somewhat brittle. This paper reports the modification of these phosphorus-containing resins by an amine-terminated butadiene-acrylonitrile copolymer (ATBN) and a perfluoroalkylene diaromatic amine elastomer (3F). An approximately two-fold increase in short beam shear strength and flexural strength was observed at 7 percent ATBN concentration. The tensile, flexural, and shear strengths were reduced when 18 percent ATBN was used. Anaerobic char yields of the resins at 800 C and the limiting oxygen indexes of the laminates decreased with increasing ATBN concentration. The perfluorodiamine (3F) was used with both imide resins at 6.4 percent concentration. The shear strength was doubled in the case of the bisimide with no loss of flammability characteristics. The modified trisimide laminate also had improved properties over the unmodified one. The dynamic mechanical analysis of a four-ply laminate indicated a glass transition temperature above 300 C. Scanning electron micrographs of the ATBN modified imide resins were also recorded.

  1. MODELING RESULTS FROM CESIUM ION EXCHANGE PROCESSING WITH SPHERICAL RESINS

    SciTech Connect

    Nash, C.; Hang, T.; Aleman, S.

    2011-01-03

    Ion exchange modeling was conducted at the Savannah River National Laboratory to compare the performance of two organic resins in support of Small Column Ion Exchange (SCIX). In-tank ion exchange (IX) columns are being considered for cesium removal at Hanford and the Savannah River Site (SRS). The spherical forms of resorcinol formaldehyde ion exchange resin (sRF) as well as a hypothetical spherical SuperLig{reg_sign} 644 (SL644) are evaluated for decontamination of dissolved saltcake wastes (supernates). Both SuperLig{reg_sign} and resorcinol formaldehyde resin beds can exhibit hydraulic problems in their granular (nonspherical) forms. SRS waste is generally lower in potassium and organic components than Hanford waste. Using VERSE-LC Version 7.8 along with the cesium Freundlich/Langmuir isotherms to simulate the waste decontamination in ion exchange columns, spherical SL644 was found to reduce column cycling by 50% for high-potassium supernates, but sRF performed equally well for the lowest-potassium feeds. Reduced cycling results in reduction of nitric acid (resin elution) and sodium addition (resin regeneration), therefore, significantly reducing life-cycle operational costs. These findings motivate the development of a spherical form of SL644. This work demonstrates the versatility of the ion exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. The value of a resin with increased selectivity for cesium over potassium can be assessed for further development.

  2. Resin-Transfer-Molding of a Tool Face

    NASA Technical Reports Server (NTRS)

    Fowler, Mike; Ehlers, Edward; Brainard, David; Kellermann, Charles

    2004-01-01

    A resin-transfer-molding (RTM) process has been devised for fabricating a matrix/graphite-cloth composite panel that serves as tool face for manufacturing other composite panels. Heretofore, RTM has generally been confined to resins with viscosities low enough that they can readily flow through interstices of cloth. The present process makes it possible to use a high-temperature, more-viscous resin required for the tool face. First, a release layer and then a graphite cloth are laid on a foam pattern that has the desired contour. A spring with an inside diameter of 3/8 in. (.9.5 mm) is placed along the long dimension of the pattern to act as a conduit for the resin. Springs with an inside diameter of 1/4 in. (.6.4 mm) are run off the larger lengthwise spring for distributing the resin over the tool face. A glass cloth is laid on top to act as breather. The whole layup is vacuum-bagged. Resin is mixed and made to flow under vacuum assistance to infiltrate the layup through the springs. The whole process takes less than a day, and the exposure of personnel to resin vapors is minimized.

  3. Devices using resin wafers and applications thereof

    DOEpatents

    Lin, YuPo J. (Naperville, IL); Henry, Michael P. (Batavia, IL); Snyder, Seth W. (Lincolnwood, IL); St. Martin, Edward (Libertyville, IL); Arora, Michelle (Woodridge, IL); de la Garza, Linda (Woodridge, IL)

    2009-03-24

    Devices incorporating a thin wafer of electrically and ionically conductive porous material made by the method of introducing a mixture of a thermoplastic binder and one or more of anion exchange moieties or cation exchange moieties or mixtures thereof and/or one or more of a protein capture resin and an electrically conductive material into a mold. The mixture is subjected to temperatures in the range of from about 60.degree. C. to about 170.degree. C. at pressures in the range of from about 0 to about 500 psig for a time in the range of from about 1 to about 240 minutes to form thin wafers. Devices include electrodeionization and separative bioreactors in the production of organic and amino acids, alcohols or esters for regenerating cofactors in enzymes and microbial cells.

  4. Mechanical Properties of Degraded PMR-15 Resin

    NASA Technical Reports Server (NTRS)

    Tsuji, Luis C.; McManus, Hugh L.; Bowles, Kenneth J.

    1998-01-01

    Thermo-oxidative aging produces a non-uniform degradation state in PMR-15 resin. A surface layer, usually attributed to oxidative degradation, forms. This surface layer has different properties from the inner material. A set of material tests was designed to separate the properties of the oxidized surface layer from the properties of interior material. Test specimens were aged at 316 C in either air or nitrogen, for durations of up to 800 hours. The thickness of the oxidized surface layer in air aged specimens, and the shrinkage and Coefficient of Thermal Expansion (CTE) of nitrogen aged specimens were measured directly. Four-point-bend tests were performed to determine modulus of both the oxidized surface layer and the interior material. Bimaterial strip specimens consisting of oxidized surface material and unoxidized interior material were constructed and used to determine surface layer shrinkage and CTE. Results confirm that the surface layer and core materials have substantially different properties.

  5. Antibacterial activity of resin rich plant extracts

    PubMed Central

    Shuaib, Mohd; Ali, Abuzer; Ali, Mohd; Panda, Bibhu Prasad; Ahmad, Mohd Imtiyaz

    2013-01-01

    Background: The in vitro antibacterial activity of resin rich methanolic extracts (RRMEs) of Commiphora myrrha, Operculina turpethum, and Pinus roxburghii. Materials and Methods: Different concentration were studied by agar-well diffusion method against Gram-positive (Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Enterococcus faecalis) and Gram-negative bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysenteriae). Results: Among all the bacterial strains tested, E. faecalis was most sensitive and S. typhi was resistant to C. myrrha and P. roxburghii. The extracts of O. turpethum were active against all tested strains in which B. subtilis and S. aureus were the most sensitive. Conclusion: This suggested that the antibacterial activity of RRMEs of O. turpethum was more than C. myrrha and P. roxburghii. This probably explains the potential of these plants against a number of infections caused by bacterial strains tested. PMID:24302834

  6. Methane production using resin-wafer electrodeionization

    DOEpatents

    Snyder, Seth W; Lin, YuPo; Urgun-Demirtas, Meltem

    2014-03-25

    The present invention provides an efficient method for creating natural gas including the anaerobic digestion of biomass to form biogas, and the electrodeionization of biogas to form natural gas and carbon dioxide using a resin-wafer deionization (RW-EDI) system. The method may be further modified to include a wastewater treatment system and can include a chemical conditioning/dewatering system after the anaerobic digestion system. The RW-EDI system, which includes a cathode and an anode, can either comprise at least one pair of wafers, each a basic and acidic wafer, or at least one wafer comprising of a basic portion and an acidic portion. A final embodiment of the RW-EDI system can include only one basic wafer for creating natural gas.

  7. Elastomers Formed In-Situ in Epoxy Resins: Chemistry and Toughening

    Microsoft Academic Search

    Alphonsus V. Pocius; William J. Schultz; Wendy L. Thompson; Randall A. Adam

    1993-01-01

    The chemistry of the in-situ formation of elastomer particles in epoxy resins is described. Under normal synthetic conditions, if one polymerizes an acrylic monomer in an epoxy resin, the resulting polymer is soluble in the epoxy resin or it grossly phase separates, depending upon the solubility parameter difference between the acrylic polymer and the epoxy resin. This work shows that

  8. Improvement of thermal and mechanical properties by control of morphologies in PES-modified epoxy resins

    Microsoft Academic Search

    K Mimura; H Ito; H Fujioka

    2000-01-01

    In order to improve both the heat resistance and the toughness of cured epoxy resins, polyethersulfone (PES) was added to a biphenyl-type epoxy resin. The dispersion state of the PES in the epoxy resin was controlled by changing the molding temperature, and the effect of the morphologies on the heat resistance and toughness of the cured resins was investigated. In

  9. Effect of Phenol\\/Formaldehyde Stoichiometry on the Modification of Epoxy Resin Using Epoxidized Novolacs

    Microsoft Academic Search

    K. P. Unnikrishnan; Eby Thomas Thachil

    2006-01-01

    Unmodified epoxy resins based on bisphenol A exhibit brittleness and low elongation after cure. This article reports the results of a study for improving the properties of epoxy resin by blending with suitable thermosets. Hybrid polymer networks of diglycidyl ether of bisphenol A (DGEBA) resin with epoxidized phenolic novolac resins (EPN) containing phenol and formaldehyde in different stoichiometric ratios were

  10. Effect of glass fiber sizing on the cure kinetics of vinyl–ester resins

    Microsoft Academic Search

    G. R. Palmese; O. A. Andersen; V. M. Karbhari

    1999-01-01

    The cure characteristics of thermosetting resins are affected by the presence of reinforcements as a result of surface–resin interactions. Surface treatments and sizing can significantly affect such interactions; hence, sizing or surface treatment selection may significantly affect resin cure characteristics. This is of particular concern in the processing of composite materials, since neat resin cure characteristics often will not provide

  11. Ion exchange resins of high loading capacity, high chloride tolerance and rapid elution for uranium recovery

    Microsoft Academic Search

    Yan

    1982-01-01

    Ion exchange process for the recovery of uranium from a pregnant carbonate lixiviant employed in uranium leaching operations in which the lixiviant is passed over a precipitation inducing anionic ion exchange resin under conditions to load the resin predominantly with non-exchangeable uranium. Non-exchangeable uranium is then recovered from the resin by eluting the resin with an aqueous acid solution having

  12. Friction and wear of friction materials containing two different phenolic resins reinforced with aramid pulp

    Microsoft Academic Search

    Seong Jin Kim; Ho Jang

    2000-01-01

    Friction and wear characteristics of automotive friction materials containing two different phenolic resins (a straight novolac resin and a modified novolac resin) were investigated using a pad-on-disk type friction tester. Six different friction materials with different relative amounts of the phenolic resins and aramid pulp were manufactured and tested. Two different test modes were employed to examine the friction characteristics

  13. Dynamic response of phenolic resin and its carbon-nanotube composites to shock wave loading

    E-print Network

    Goddard III, William A.

    Dynamic response of phenolic resin and its carbon-nanotube composites to shock wave loading B of phenolic resin and its carbon-nanotube CNT composites to shock wave compression. For phenolic resin, our­plastic transition is characterized by shear stress relaxation and atomic-level slip, and phenolic resin shows strong

  14. Allocation of photoassimilates to biomass, resin and carbohydrates in Grindelia chiloensis as affected by light intensity

    Microsoft Academic Search

    J. A Zavala; D. A Ravetta

    2001-01-01

    Grindelia chiloensis (Asteraceae) is a shrub native to Patagonia, Argentina, and can accumulate as much as 25% resin (on a dry weight basis) in leaves. The resin can be used in applications similar to those of pine resins. Reductions in available radiation are thought to decrease both the plant C:N ratio and resin production. The objective of this study was

  15. Simulating three-dimensional flow in compression resin transfer molding process

    Microsoft Academic Search

    Pavel Simacek; Suresh G. Advani

    2005-01-01

    Compression Resin Transfer Molding (CRTM) is a novel variation of traditional Resin Transfer Molding (RTM). It combines features of RTM, with those of traditional compression molding. The resin is introduced in the mold containing the preform in the narrow gap between the mold platen and the preform. As the resin flows in the narrow gap between mold and the preform,

  16. Heat Transfer Analysis of Non-isothermal Resin Transfer Molding by the Finite Element Method

    Microsoft Academic Search

    D. M. Gao; F. Trochu; R. Gauvin

    1995-01-01

    In resin transfer molding (RTM) a stack of fiber mats or woven rovings is laid in the mold cavity. Then the mold is sealed and resin is injected. The mold and the resin can be heated in order to accelerate, by diminishing the viscosity of the resin, the filling of the mold. Proper care must be given so that polymerization

  17. Non-isothermal preform infiltration during the vacuum-assisted resin transfer molding (VARTM) process

    E-print Network

    Grujicic, Mica

    Non-isothermal preform infiltration during the vacuum-assisted resin transfer molding (VARTM conditions within a high-permeability resin-distribution medium based vacuum-assisted resin transfer molding.V. All rights reserved. PACS: 61.41.+e (Polymers) Keywords: Vacuum-assisted resin transfer molding (VARTM

  18. Moisture diffusion parameter characteristics for epoxy composites and neat resins

    NASA Technical Reports Server (NTRS)

    Long, E. R., Jr.

    1979-01-01

    The moisture absorption characteristics of two graphite/epoxy composites and their corresponding cured neat resins were studied in high humidity and water immersion environments at elevated temperatures. Moisture absorption parameters, such as equilibrium moisture content and diffusion coefficient derived from data taken on samples exposed to high humidity and water soak environments, were compared. Composite swelling in a water immersion environment was measured. Tensile strengths of cured neat resin were measured as a function of their equilibrium moisture content after exposure to different moisture environments. The effects of intermittent moderate tensile loads on the moisture absorption parameters of composite and cured neat resin samples were determined.

  19. Statistical failure analysis of adhesive resin cement bonded dental ceramics

    PubMed Central

    Wang, Yaou; Katsube, Noriko; Seghi, Robert R; Rokhlin, Stanislav I.

    2007-01-01

    The goal of this work is to quantitatively examine the effect of adhesive resin cement on the probability of crack initiation from the internal surface of ceramic dental restorations. The possible crack bridging mechanism and residual stress effect of the resin cement on the ceramic surface are examined. Based on the fracture-mechanics-based failure probability model, we predict the failure probability of glass-ceramic disks bonded to simulated dentin subjected to indentation loads. The theoretical predictions match experimental data suggesting that both resin bridging and shrinkage plays an important role and need to be considered for accurate prognostics to occur. PMID:18670583

  20. Facile synthesis and characterization of novel pseudo-hypercrosslinked resin

    Microsoft Academic Search

    Si Guo Yuan; Shao Hui Zhang; Wei Hua Zou; Yong Hao Zhou; Xiao Hui Zhou

    2008-01-01

    A kind of pseudo-hypercrosslinked polymer resin was firstly synthesized via a continuous Friedel–Crafts alkylation polymerization of benzene, diphenyl and their dichloromethyl derivatives. And the micromorphology and adsorption properties of these resins were investigated. The results demonstrated that the novel resins have high-specific surface area (581.26–974.88m2\\/g), high-pore volume (0.56–1.65mL\\/g), small average porous radius (1.93–3.67nm) and excellent adsorption properties for small non-polar

  1. Cryogenic compressive properties of basic epoxy resin systems

    SciTech Connect

    Markley, F.W.; Hoffman, J.A.; Muniz, D.P.

    1985-09-01

    The compressive properties of short cylindrical samples of many different epoxy resin systems have been measured at ambient temperature and at 77/sup 0/K. These are pure resin systems of known chemistry, without the inorganic fillers or fibrous reinforcements needed in final cryogenic systems. Of course, chemically incorporated modifiers such as flexibilizing resins have been included. This data should make possible inferences about cryogenic properties from molecular structures and provide specific data useful to formulators and end users. Measurements on some other plastics such as PTFE, Polyimides, and UHMWPE have been made for comparison purposes.

  2. Advanced thermoset resins for fire-resistant composites

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.

    1979-01-01

    The thermal and flammability properties of some thermoset polymers and composites are described. The processing and evaluation of composites fabricated from currently used resins and advanced fire-resistant resins are also described. Laboratory test methodology used to qualify candidate composite materials includes thermochemical characterization of the polymeric compounds and evaluation of the glass reinforced composites for flammability and smoke evolution. The use of these test methods will be discussed in comparing advanced laminating resins and composites consisting of modified epoxies, phenolics and bismaleimide, with conventional baseline materials consisting of epoxy.

  3. Dissolution of mega-voids in resin transfer molding

    NASA Astrophysics Data System (ADS)

    Clark, Paul Nordstrom

    Resin transfer molding (RTM) is a common composite manufacturing process. Voids are a common defect encountered in RTM components. A new type of void, the 'Mega-Void', has been identified and addressed by this research. To produce acceptable RTM components requires that the mega-void be eliminated either through prevention or through dissolution. The latter is the topic of this research. Three process parameters affecting mega-void dissolution are researched; (1) Preform/mold vacuum, (2) Resin degas, and (3) Resin curing pressure. To address preform/mold vacuum, analytical and empirical investigations were carried out. Results show that the preform can take-up and retain water. Additional analytical investigations show that gas flow within the preform is molecular in nature. The consequence of this finding is that the removal of moisture and gases from the preform is difficult. Confirming experiments were carried out showing a significant difference between gas pressures within the mold and the gas pressure external to the mold. The resin degas and resin curing pressure parameters were studied by researching the solubility of air in epoxy. An experimental apparatus was designed and fabricated wherein a sample of resin could be subjected to a specified level of vacuum for degassing. Subsequently, a measured amount of air was introduced into the resin sample and the combination pressurized to a controlled pressure. The resin and air were then monitored over time to observe the shrinkage of the air pocket as the air was absorbed by the resin. The experimental results show the pressure of residual air and the resin dissolution pressure both significantly affect the absorption of the air pocket. Higher levels of resin degassing are shown to provide a small benefit to gas dissolution. As a final research effort, composite panels were fabricated using a blind injection setup where a single mold port is used for evacuation and resin injection. In this way, the starting size of the mega-void is fixed and equal to the mold free volume. The three processing parameters were varied in order to show the dissolution of mega-voids when the appropriate parameters are used.

  4. Infiltration/cure modeling of resin transfer molded composite materials using advanced fiber architectures

    NASA Technical Reports Server (NTRS)

    Loos, Alfred C.; Weideman, Mark H.; Long, Edward R., Jr.; Kranbuehl, David E.; Kinsley, Philip J.; Hart, Sean M.

    1991-01-01

    A model was developed which can be used to simulate infiltration and cure of textile composites by resin transfer molding. Fabric preforms were resin infiltrated and cured using model generated optimized one-step infiltration/cure protocols. Frequency dependent electromagnetic sensing (FDEMS) was used to monitor in situ resin infiltration and cure during processing. FDEMS measurements of infiltration time, resin viscosity, and resin degree of cure agreed well with values predicted by the simulation model. Textile composites fabricated using a one-step infiltration/cure procedure were uniformly resin impregnated and void free. Fiber volume fraction measurements by the resin digestion method compared well with values predicted using the model.

  5. Extraction chromatography of neodymium by an organophosphorous extractant supported on various polymeric resins

    SciTech Connect

    Takigawa, D.Y.

    1993-04-01

    Fifteen resins coated with dihexyl-N,N-diethylcarbamoylmethyl phosphonate (CMP) were studied for their extraction of neodymium (Nd) in 4.0 and 7.0 M nitric acid. Resin properties, such as chemical composition and physical morphology, which can influence Nd extraction as well as subsequent resin regeneration (Nd stripping), were identified. Hydrophilic or polar resins coated with CMP efficiently extracted the Nd. Resins initially washed free of residual monomer and solvent before CMP coating outperformed their untreated counterparts. The macroporous styrene-divinylbenzene hydrophobic resins that were high in surface area were less effective supports compared with hydrophilic microporous Aurorez, polybenzimidazole (PBI) and macroporous Amberlite polyacrylic resins. Only one resin, Duolite C-467, showed no measurable improvement in Nd extraction with CMP coating. CMP-coated Aurorez PBI, a microporous and hydrophilic polymeric resin with an average surface area, showed the best overall efficiency for Nd removal and resin regeneration.

  6. Low-density resin impregnated ceramic article and method for making the same

    NASA Technical Reports Server (NTRS)

    Tran, Huy K. (Inventor); Henline, William D. (Inventor); Hsu, Ming-ta S. (Inventor); Rasky, Daniel J. (Inventor); Riccitiello, Salvatore R. (Inventor)

    1997-01-01

    A low-density resin impregnated ceramic article advantageously employed as a structural ceramic ablator comprising a matrix of ceramic fibers. The fibers of the ceramic matrix are coated with an organic resin film. The organic resin can be a thermoplastic resin or a cured thermosetting resin. In one embodiment, the resin is uniformly distributed within the ceramic article. In a second embodiment, the resin is distributed so as to provide a density gradient along at least one direction of the ceramic article. The resin impregnated ceramic article is prepared by providing a matrix of ceramic fibers; immersing the matrix of ceramic fibers in a solution of a solvent and an organic resin infiltrant; and removing the solvent to form a resin film on the ceramic fibers.

  7. Dispersion Properties of a Water-Soluble PhenolFormaldehyde Resin

    Microsoft Academic Search

    Limei Sun; Mingyuan Li; Meiqin Lin; Bo Peng; Jixiang Guo

    2009-01-01

    Dispersion properties of the water soluble phenol-formaldehyde resin are studied by measuring of hydrodynamic diameter, Zeta potential of the resin molecule aggregate and the critical coagulating concentration of the resin solution. The results shows that a 50 mg\\/L resin solution prepared with distilled water is transparent, in which the hydrodynamic diameter and the Zeta potential of the resin molecule aggregate is

  8. Comparative Evaluation of Sorption, Solubility and Microhardness of Heat Cure Polymethylmethacrylate Denture Base Resin & Flexible Denture Base Resin

    PubMed Central

    Bulbule, Nilesh; Kulkarni, Shilpa; Shah, Riddhi; Kakade, Dilip

    2014-01-01

    Aim: The aim of the study was to evaluate and compare sorption, solubility and microhardness of heat cure polymethylmethacrylate (PMMA) denture base resin and flexible (thermoplastic polyamide nylon) denture base resin. Materials and Methods: Sorption, solubility and microhardness were assessed to determine compliance with ADA Specification no. 12. Results were assessed using statistical and observational analyses. Result: All materials satisfied ADA requirements for sorption, solubility and microhardness. Heat cure PMMA showed more sorption, solubility and microhardness than flexible (thermoplastic polyamide nylon). Conclusion: Flexible (thermoplastic polyamide nylon) resin absorbs less water, is less soluble and is more flexible than PMMA. PMID:25302291

  9. High-capacity carbons prepared from phenolic resin for phenolic resin for anodes of lithium-ion batteries

    SciTech Connect

    Zheng, T.; Dahn, J.R. [Simon Fraser Univ., Burnaby, British Columbia (Canada). Dept. of Physics; Zhong, Q. [Moli Energy Limited, Maple Ridge, British Columbia (Canada)

    1995-11-01

    Carbons were made from resol and novolak resins at temperatures from 700 to 1,100 C by pyrolysis in inert gas. Using electrochemical methods, the authors have studied the insertion of lithium within these materials. Resol resin, heated to 1,000 C, has a reversible capacity of about 550 mAh/g, shows little hysteresis, and exhibits good cycling performance. Since these resins cost about 2.2 $/kg and the pyrolysis yields are over 50%, they feel that inexpensive carbons for Li-ion cells can be prepared by this route.

  10. 21 CFR 172.215 - Coumarone-indene resin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...additive coumarone-indene resin may be safely used on grapefruit, lemons, limes, oranges, tangelos, and tangerines in accordance...or intended for use as a protective coating for grapefruit, lemons, limes, oranges, tangelos, and tangerines whereby the...

  11. 21 CFR 172.215 - Coumarone-indene resin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...additive coumarone-indene resin may be safely used on grapefruit, lemons, limes, oranges, tangelos, and tangerines in accordance...or intended for use as a protective coating for grapefruit, lemons, limes, oranges, tangelos, and tangerines whereby the...

  12. 21 CFR 172.215 - Coumarone-indene resin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...additive coumarone-indene resin may be safely used on grapefruit, lemons, limes, oranges, tangelos, and tangerines in accordance...or intended for use as a protective coating for grapefruit, lemons, limes, oranges, tangelos, and tangerines whereby the...

  13. 21 CFR 172.215 - Coumarone-indene resin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...additive coumarone-indene resin may be safely used on grapefruit, lemons, limes, oranges, tangelos, and tangerines in accordance...or intended for use as a protective coating for grapefruit, lemons, limes, oranges, tangelos, and tangerines whereby the...

  14. 21 CFR 172.215 - Coumarone-indene resin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...additive coumarone-indene resin may be safely used on grapefruit, lemons, limes, oranges, tangelos, and tangerines in accordance...or intended for use as a protective coating for grapefruit, lemons, limes, oranges, tangelos, and tangerines whereby the...

  15. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...3300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a)...

  16. 21 CFR 872.3310 - Coating material for resin fillings.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3310 Coating...to be applied to the surface of a restorative resin dental filling to attain a smooth, glaze-like finish...

  17. 21 CFR 872.3670 - Resin impression tray material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin...material is a device intended for use in a two-step dental mold fabricating process. The device...

  18. 21 CFR 872.3310 - Coating material for resin fillings.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3310 Coating...to be applied to the surface of a restorative resin dental filling to attain a smooth, glaze-like finish...

  19. 21 CFR 872.3670 - Resin impression tray material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin...material is a device intended for use in a two-step dental mold fabricating process. The device...

  20. 21 CFR 872.3670 - Resin impression tray material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin...material is a device intended for use in a two-step dental mold fabricating process. The device...

  1. 21 CFR 872.3310 - Coating material for resin fillings.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3310 Coating...to be applied to the surface of a restorative resin dental filling to attain a smooth, glaze-like finish...

  2. 21 CFR 872.3820 - Root canal filling resin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A...

  3. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...3300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a)...

  4. 21 CFR 872.3310 - Coating material for resin fillings.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3310 Coating...to be applied to the surface of a restorative resin dental filling to attain a smooth, glaze-like finish...

  5. 21 CFR 872.3670 - Resin impression tray material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin...material is a device intended for use in a two-step dental mold fabricating process. The device...

  6. 21 CFR 872.3200 - Resin tooth bonding agent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification....

  7. 21 CFR 872.3670 - Resin impression tray material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin...material is a device intended for use in a two-step dental mold fabricating process. The device...

  8. 21 CFR 872.3310 - Coating material for resin fillings.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3310 Coating...to be applied to the surface of a restorative resin dental filling to attain a smooth, glaze-like finish...

  9. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...resin produced by reacting polyphenylene sulfide with peracetic acid such that the finished...of this section. The polyphenylene sulfide used to manufacture polyphenylene sulfone is prepared by the reaction of sodium sulfide and p -dichlorobenzene, and has...

  10. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...resin produced by reacting polyphenylene sulfide with peracetic acid such that the finished...of this section. The polyphenylene sulfide used to manufacture polyphenylene sulfone is prepared by the reaction of sodium sulfide and p -dichlorobenzene, and has...

  11. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...resin produced by reacting polyphenylene sulfide with peracetic acid such that the finished...of this section. The polyphenylene sulfide used to manufacture polyphenylene sulfone is prepared by the reaction of sodium sulfide and p -dichlorobenzene, and has...

  12. CHARACTERIZATION OF SORBENT RESINS FOR USE IN ENVIRONMENTAL SAMPLING

    EPA Science Inventory

    The report describes the use of chromatographic techniques to characterize resins which are used to trap vapors in environmental sampling schemes. It describes two such techniques (frontal and elution analysis) which have been applied to characterize sorbent cartridges packed wit...

  13. Photonic patterns printed in chiral nematic mesoporous resins.

    PubMed

    Khan, Mostofa K; Bsoul, Anas; Walus, Konrad; Hamad, Wadood Y; MacLachlan, Mark J

    2015-03-27

    Chiral nematic mesoporous phenol-formaldehyde resins, which were prepared using cellulose nanocrystals as a template, can be used as a substrate to produce latent photonic images. These resins undergo swelling, which changes their reflected color. By writing on the films with chemical inks, the density of methylol groups in the resin changes, subsequently affecting their degree of swelling and, consequently, their color. Writing on the films gives latent images that are revealed only upon swelling of the films. Using inkjet printing, it is possible to make higher resolution photonic patterns both as text and images that can be visualized by swelling and erased by drying. This novel approach to printing photonic patterns in resin films may be applied to anti-counterfeit tags, signage, and decorative applications. PMID:25682748

  14. Elastomer-modified phosphorus-containing imide resins

    NASA Technical Reports Server (NTRS)

    Varma, I. K.; Fohlen, G. M.; Parker, J. A. (inventors)

    1983-01-01

    Phosphine oxide-containing polyimide resins modified by elastomers, are disclosed which have improved mechanical properties. These products are particularly useful in the production of fiber or fabric-reinforced composites or laminates.

  15. 21 CFR 177.2490 - Polyphenylene sulfide resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...in Organic Compounds,” “Determination of the Inherent Viscosity of Polyphenylene Sulfide,” and “Analysis for Dichlorobenzene...percent by weight of finished resin. (2) Minimum inherent viscosity: 0.13 deciliters per gram. (3) Maximum residual...

  16. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

  17. 21 CFR 177.2490 - Polyphenylene sulfide resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...in Organic Compounds,” “Determination of the Inherent Viscosity of Polyphenylene Sulfide,” and “Analysis for Dichlorobenzene...percent by weight of finished resin. (2) Minimum inherent viscosity: 0.13 deciliters per gram. (3) Maximum residual...

  18. 21 CFR 177.2490 - Polyphenylene sulfide resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...in Organic Compounds,” “Determination of the Inherent Viscosity of Polyphenylene Sulfide,” and “Analysis for Dichlorobenzene...percent by weight of finished resin. (2) Minimum inherent viscosity: 0.13 deciliters per gram. (3) Maximum residual...

  19. 21 CFR 177.2490 - Polyphenylene sulfide resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...in Organic Compounds,” “Determination of the Inherent Viscosity of Polyphenylene Sulfide,” and “Analysis for Dichlorobenzene...percent by weight of finished resin. (2) Minimum inherent viscosity: 0.13 deciliters per gram. (3) Maximum residual...

  20. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

  1. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

  2. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

  3. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

  4. 21 CFR 177.2490 - Polyphenylene sulfide resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...in Organic Compounds,” “Determination of the Inherent Viscosity of Polyphenylene Sulfide,” and “Analysis for Dichlorobenzene...percent by weight of finished resin. (2) Minimum inherent viscosity: 0.13 deciliters per gram. (3) Maximum residual...

  5. 21 CFR 872.3200 - Resin tooth bonding agent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3200 Resin tooth...interior of a prepared cavity of a tooth to improve retention of a restoration, such as a filling. (b) Classification. Class...

  6. 21 CFR 872.3200 - Resin tooth bonding agent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3200 Resin tooth...interior of a prepared cavity of a tooth to improve retention of a restoration, such as a filling. (b) Classification. Class...

  7. 21 CFR 872.3200 - Resin tooth bonding agent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3200 Resin tooth...interior of a prepared cavity of a tooth to improve retention of a restoration, such as a filling. (b) Classification. Class...

  8. 21 CFR 173.5 - Acrylate-acrylamide resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...prescribed conditions: (a) The additive consists of one of the following: (1) Acrylamide-acrylic acid resin (hydrolyzed polyacrylamide) is produced by the polymerization of acrylamide with partial hydrolysis, or by copolymerization of...

  9. 21 CFR 173.5 - Acrylate-acrylamide resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...prescribed conditions: (a) The additive consists of one of the following: (1) Acrylamide-acrylic acid resin (hydrolyzed polyacrylamide) is produced by the polymerization of acrylamide with partial hydrolysis, or by copolymerization of...

  10. 21 CFR 173.5 - Acrylate-acrylamide resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...prescribed conditions: (a) The additive consists of one of the following: (1) Acrylamide-acrylic acid resin (hydrolyzed polyacrylamide) is produced by the polymerization of acrylamide with partial hydrolysis, or by copolymerization of...

  11. 21 CFR 173.5 - Acrylate-acrylamide resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...prescribed conditions: (a) The additive consists of one of the following: (1) Acrylamide-acrylic acid resin (hydrolyzed polyacrylamide) is produced by the polymerization of acrylamide with partial hydrolysis, or by copolymerization of...

  12. 21 CFR 173.5 - Acrylate-acrylamide resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...prescribed conditions: (a) The additive consists of one of the following: (1) Acrylamide-acrylic acid resin (hydrolyzed polyacrylamide) is produced by the polymerization of acrylamide with partial hydrolysis, or by copolymerization of...

  13. Quantification and Purification of Mulberry Anthocyanins With Macroporous Resins

    PubMed Central

    Liu, Xueming

    2004-01-01

    Total anthocyanins in different cultivars of mulberry were measured and a process for the industrial preparation of mulberry anthocyanins as a natural food colorant was studied. In 31 cultivars of mulberry, the total anthocyanins, calculated as cyanidin 3-glucoside, ranged from 147.68 to 2725.46?mg/L juice. Extracting and purifying with macroporous resins was found to be an efficient potential method for the industrial production of mulberry anthocyanins as a food colorant. Of six resins tested, X-5 demonstrated the best adsorbent capability for mulberry anthocyanins (91?mg/mL resin). The adsorption capacity of resins increased with the surface area and the pore radius. Residual mulberry fruit juice after extraction of pigment retained most of its nutrients, except for anthocyanins, and may provide a substrate for further processing. PMID:15577197

  14. 21 CFR 181.32 - Acrylonitrile copolymers and resins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...copolymer—no restrictions. (2) Coatings. (i) Acrylonitrile/butadiene copolymer...chloride resin—for use only as extruded pipe. (b) Limitations for acrylonitrile...using the method of analysis titled “Gas-Solid Chromatographic...

  15. 21 CFR 181.32 - Acrylonitrile copolymers and resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...copolymer—no restrictions. (2) Coatings. (i) Acrylonitrile/butadiene copolymer...chloride resin—for use only as extruded pipe. (b) Limitations for acrylonitrile...using the method of analysis titled “Gas-Solid Chromatographic...

  16. 21 CFR 181.32 - Acrylonitrile copolymers and resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...copolymer—no restrictions. (2) Coatings. (i) Acrylonitrile/butadiene copolymer...chloride resin—for use only as extruded pipe. (b) Limitations for acrylonitrile...using the method of analysis titled “Gas-Solid Chromatographic...

  17. 21 CFR 181.32 - Acrylonitrile copolymers and resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...copolymer—no restrictions. (2) Coatings. (i) Acrylonitrile/butadiene copolymer...chloride resin—for use only as extruded pipe. (b) Limitations for acrylonitrile...using the method of analysis titled “Gas-Solid Chromatographic...

  18. 21 CFR 181.32 - Acrylonitrile copolymers and resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...copolymer—no restrictions. (2) Coatings. (i) Acrylonitrile/butadiene copolymer...chloride resin—for use only as extruded pipe. (b) Limitations for acrylonitrile...using the method of analysis titled “Gas-Solid Chromatographic...

  19. Vacuum assisted resin transfer molding (VARTM): Model development and verification

    NASA Astrophysics Data System (ADS)

    Song, Xiaolan

    2003-06-01

    In this investigation, a comprehensive Vacuum Assisted Resin Transfer Molding (VARTM) process simulation model was developed and verified. The model incorporates resin flow through the preform, compaction and relaxation of the preform, and viscosity and cure kinetics of the resin. The computer model can be used to analyze the resin flow details, track the thickness change of the preform, predict the total infiltration time and final fiber volume fraction of the parts, and determine whether the resin could completely infiltrate and uniformly wet out the preform. Flow of resin through the preform is modeled as flow through porous media. Darcy's law combined with the continuity equation for an incompressible Newtonian fluid forms the basis of the flow model. During the infiltration process, it is well accepted that the total pressure is shared by the resin pressure and the pressure supported by the fiber network. With the progression of the resin, the net pressure applied to the preform decreases as a result of increasing local resin pressure. This leads to the springback of the preform, and is called the springback mechanism. On the other side, the lubrication effect of the resin causes the rearrangement of the fiber network and an increase in the preform compaction. This is called the wetting compaction mechanism. The thickness change of the preform is determined by the relative magnitude of the springback and wetting deformation mechanisms. In the compaction model, the transverse equilibrium equation is used to calculate the net compaction pressure applied to the preform, and the compaction test results are fitted to give the compressive constitutive law of the preform. The Finite Element/Control Volume (FE/CV) method is adopted to find the flow front location and the fluid pressure. The code features the ability of simultaneous integration of 1-D, 2-D and 3-D element types in a single simulation, and thus enables efficient modeling of the flow in complex mold geometries. VARTM of two flat composite panels was conducted to verify the simulation model. The composite panels were fabricated using the SAERTEX multi-axial warp knit carbon fiber fabric and SI-ZG-5A epoxy resin. (Abstract shortened by UMI.)

  20. Humidity sensor using epoxy resin containing quaternary ammonium salts

    Microsoft Academic Search

    Chil-Won Lee; Hee-Woo Rhee; Myoung-Seon Gong

    2001-01-01

    Humidity-sensitive epoxy monomer, glycidyl trimethyl ammonium chloride (GTMAC) was selected as the humidity-sensing resin. Polypropylene glycol diglycidyl ether (PPGDGE) and methyl tetrahydrophthalic anhydride (MTPHA) were used as a comonomer and a curing agent, respectively. The humidity-sensitive membranes were composed of GTMAC, PPGDGE and MTPHA. When impedance characteristics of the epoxy resins containing quaternary ammonium salts were measured, the impedance decreased

  1. Fluorinated diamond particles bonded in a filled fluorocarbon resin matrix

    DOEpatents

    Taylor, Gene W. (Los Alamos, NM); Roybal, Herman E. (Santa Fe, NM)

    1985-01-01

    A method of producing fluorinated diamond particles bonded in a filled fluorocarbon resin matrix. Simple hot pressing techniques permit the formation of such matrices from which diamond impregnated grinding tools and other articles of manufacture can be produced. Teflon fluorocarbon resins filled with Al.sub.2 O.sub.3 yield grinding tools with substantially improved work-to-wear ratios over grinding wheels known in the art.

  2. Enrichment of lithium isotopes by a triazacrown trimerrifield peptide resin

    Microsoft Academic Search

    D. W. Kim

    2002-01-01

    A study on the elution chromatographic separation of lithium isotopes was carried out with a triazacrown trimerrifield peptide resin. The capacity of the triazacrown trimerrifield peptide resin has a value of 0.08 meq\\/g. Upon column chromatography [0.2 cm (I.D)×35 cm (height)] using 4.0M NH4Cl solution as an eluent, the single stage separation factor of 1.028 was obtained by the Glueckauf

  3. Lithium isotope separation on a monobenzo-15-crown-5 resin

    Microsoft Academic Search

    D. W. Kim; Y. S. Jeon; T. Y. Eom; M. Y. Suh; C. H. Lee

    1991-01-01

    A study on the separation of Li isotopes was carried out with a resin having monobenzo-15-crown-5 as a functional group, synthesized by substitution reaction of chloromethylated styrene-DVB copolymer with 4-aminobenzo-15-crown-5. Adsorption properties of the resin for Li+ were invesgated with batch method in various solvents and counter anions. Upon column chromatography [0.9 cm (I. D.)×25 cm (height)] using 5% (v\\/v)

  4. Separation of lithium isotope by azacrown tetramerrifield peptide resin

    Microsoft Academic Search

    D. W. Kim; B. K. Kim; S. R. Park; N. S. Lee; Y. S. Jeon; K. Y. Choi; Y. I. Lee

    1998-01-01

    A study on the separation of lithium isotope was carried out with N4O azacrown ion exchange resin. The lighter6Li isotope concentrated in the solution phase, while the heavier7Li isotope is enriched in the resin phase. Upon column chromatography (0.3 cm I.D.×15.5cm height) using 0.5M NH4Cl as an eluent, single separation factor, ?=1.00127 was obtained.

  5. Apparent Interfacial Fracture Toughness of Resin\\/Ceramic Systems

    Microsoft Academic Search

    A. Della Bona; K. J. Anusavice; J. J. Mecholsky

    2006-01-01

    We suggest that the apparent interfacial fracture toughness (KA) may be estimated by fracture mechanics and fractography. This study tested the hypothesis that the KA of the adhesion zone of resin\\/ceramic systems is affected by the ceramic microstructure. Lithia disilicate-based (Empress2-E2) and leucite-based (Empress-E1) ceramics were surface-treated with hydrofluoric acid (HF) and\\/or silane (S), followed by an adhesive resin. Microtensile

  6. Production scheduling of a multi-grade PET resin plant

    Microsoft Academic Search

    George Liberopoulos; George Kozanidis; Olympia Hatzikonstantinou

    2010-01-01

    We present a discrete-time, Mixed Integer Linear Programming (MILP) model for the production schedul- ing of a continuous-process multi-grade PET resin plant. The objective is to minimize the cost associated with grade changeovers in order to avoid undesirable variations in base resin properties and process conditions that occur during such changes. The constraints of the model include requirements related to

  7. Acetoxylation of methyl oleate with a resin catalyst

    Microsoft Academic Search

    L. T. Black; R. E. Beal

    1967-01-01

    The reaction of methyl oleate with acetic acid in the presence of a reticulated cation exchange resin produces methyl acetoxystearate.\\u000a Saponification of this compound and subsequent acidification yields hydroxystearic acid. Time, temperature, acetic acid:ester\\u000a ratio, and resin:ester ratio were examined for their effect on yield of methyl acetoxystearate. A yield of approximately 45%\\u000a of theory was reached under the best

  8. Respiratory morbidity in workers exposed to dust containing phenolic resin

    Microsoft Academic Search

    Patricia Jo Sparks; John M. Peters

    1980-01-01

    Summary Seventy-three men and women exposed to phenolic resin dust and\\/or processed cotton dust in a factory producing sound-deadening material were studied cross-sectionally. There was a statistically significant acute drop in FEV1 and FVC over the shift in garnett-line workers exposed to dust containing phenolic resin. Pickers, exposed to processed cotton dust only, did not show a significant drop in

  9. [Effect of ion exchange resins on the composition of milk].

    PubMed

    Bonnet, L; Goudable, J; Accominotti, M; Fontaine, D; Cochat, P

    1997-01-01

    Pretreatment of milk with either sodium or calcium polystyrene sulfonate resins is useful in limiting potassium dietary intake in children with renal failure. We therefore studied the in vitro effects of Kayexalate and Calcium Sorbisterit on potassium, sodium and calcium concentrations in 3 standard formulas and in human milk. It is concluded that wide variations in the final potassium, sodium and calcium concentrations can be observed according to the resin but also to the formula. PMID:9496569

  10. A NOVEL STRONTIUM-SELECTIVE EXTRACTION CHROMATOGRAPHIC RESIN

    Microsoft Academic Search

    E. Philip Horwitz; Renato Chiarizia; Mark L. Dietz

    1992-01-01

    The effect of nitric acid concentration on the selectivity of a novel extraction chromatographic resin consisting of an octanol solution of 4,4?(5?)-bis(t-butyl-cyclohexano)-18-crown-6 sorbed on an inert polymeric support for strontium over a number of alkali, alkaline earth, and other metal cations was evaluated. The effect of macro quantities of selected elements on strontium retention by the resin was also examined.

  11. SuperLig Ion Exchange Resin Swelling and Buoyancy Study

    SciTech Connect

    Hassan, N.M.

    2000-07-27

    The objective of this study was to achieve a fundamental understanding of SuperLig resin swelling and shrinking characteristics, which lead to channeling and early breakthrough during loading cycles. The density of salt solution that causes resin floating was also determined to establish a limit for operation. Specific tests performed include (a) pH dependence, (b) ionic strength dependence and (c) buoyancy effect vs. simulant composition.

  12. Characterization and Process Development of Cyanate Ester Resin and Composite

    SciTech Connect

    Frame, B.J.

    1998-03-01

    Cyanate ester (or polycyanate) resins offer advantages as composite matrices because of their high thermal stability, low outgassing, low water absorption and radiation resistance. This report describes the results of a processing study to develop high-strength hoop-wound composite by the wet-filament winding method using Toray T1000G carbon fiber and YLA RS-14A polycyanate resin as the constituent materials. Process trials, tests and analyses were conducted in order to gain insight into factors that can affect final properties of the cured cyanate ester resin and its composites. The study shows that the cyanate ester resin has a broad process envelope but that an inert-atmosphere cure is essential for obtaining optimum resin and composite properties. Minimizing moisture exposure prior to cure is also crucial as it affects the T{sub g} of the resin and composite. Recommendations for reducing moisture contact with the resin during wet-winding are presented. High fiber volume fraction ({approximately}80%) composites wound and cured with these methods yielded excellent hoop tensile strengths (660 to 670 ksi average with individual rings failing above 700 ksi), which are believed to be the highest recorded strengths for this class of materials. The measured transverse properties were also exceptional for these high fiber fraction composites. Based on the available data, this cyanate ester resin system and its composites are recommended for space and vacuum applications only. Further testing is required before these materials can be recommended for long term use at elevated temperatures in an ambient air environment. The results of all analyses and tests performed as part of this study are presented as well as baseline process for fabricating thick, stage-cured composites. The manufacture of a 1 in. thick composite cylinder made with this process is also described.

  13. Effect of filler size on wear resistance of resin cement

    Microsoft Academic Search

    Koichi Shinkai; Shiro Suzuki; Yoshiroh Katoh

    2001-01-01

    The purpose of this study was to evaluate the effect of filler size on the wear of resin cements. Materials tested included\\u000a four experimental dual-cure resin cements (Kuraray) consisting of different-sized filler particles. A rectangular box cavity\\u000a was prepared on the flattened occlusal surface of extracted human molars. Ceramic inlays for the cavities were fabricated\\u000a using the Cerec 2 system.

  14. WETTING BEHAVIORS OF PHENOL AND UREAFORMALDEHYDE RESINS AS COMPATIBILIZERS1

    Microsoft Academic Search

    Sangyeob Lee; Todd F. Shupe; Leslie H. Groom

    Understanding wetting behavior and surface coverage of resins on a wood surface is important to obtain satisfactory adhesion and optimize adhesive application for wood composite manufacturing. Sessile and micro-droplets of urea- and phenol-formaldehyde (UF and PF) resins were generated on wood surfaces to observe wetting behaviors using three directional image generation system and atomic force microscopy (AFM). The generated micro-droplet

  15. Optimization of Sulforaphane Separation from Broccoli Seeds by Macroporous Resins

    Microsoft Academic Search

    Chunfang Li; Hao Liang; Qipeng Yuan; Xiaodan Hou

    2008-01-01

    In this study, the adsorption and desorption properties of sulforaphane on macroporous resins (HP20, SP207, SP850, and HP2MGL) were investigated. Analysis revealed that SP850 resin was most effective in the separation of sulforaphane. The equilibrium experimental data obtained at different temperatures were well fitted to the Langmuir and Freundlich isotherms. To optimize the separation process, dynamic adsorption and desorption tests

  16. Resin hemoperfusion in dogs intoxicated with ethchlorvynol (Placidyl®)

    Microsoft Academic Search

    Michael J Zmuda

    1980-01-01

    Resin hemoperfusion in dogs intoxicated with ethchlorvynol (Placidyl®). Kinetic parameters were studied to determine the effectiveness of hemoperfusion in removing ethchlorvynol from the plasma and red blood cells (RBC) of intoxicated dogs. Perfusion columns contained polystyrene\\/divinyl benzene resin (XAD-4 Amberlite(®)). Column clearances of ethchlorvynol averaged 96.5 ± 0.4% of the plasma flow rate (mean ± SEM, 9 dogs). Plasma ethchlorvynol

  17. Enhanced vanillin production from ferulic acid using adsorbent resin

    Microsoft Academic Search

    Dongliang Hua; Cuiqing Ma; Lifu Song; Shan Lin; Zhaobin Zhang; Zixin Deng; Ping Xu

    2007-01-01

    High vanillin productivity was achieved in the batch biotransformation of ferulic acid by Streptomyces sp. strain V-1. Due to the toxicity of vanillin and the product inhibition, fed-batch biotransformation with high concentration\\u000a of ferulic acid was unsuccessful. To solve this problem and improve the vanillin yield, a biotransformation strategy using\\u000a adsorbent resin was investigated. Several macroporous adsorbent resins were chosen

  18. Fluorinated diamond particles bonded in a filled fluorocarbon resin matrix

    DOEpatents

    Taylor, G.W.; Roybal, H.E.

    1983-11-14

    A method of producing fluorinated diamond particles bonded in a filled fluorocarbon resin matrix. Simple hot pressing techniques permit the formation of such matrices from which diamond impregnated grinding tools and other articles of manufacture can be produced. Teflon fluorocarbon resins filled with Al/sub 2/O/sub 3/ yield grinding tools with substantially improved work-to-wear ratios over grinding wheels known in the art.

  19. Cyanide regeneration by AVR process using ion exchange polymeric resins

    Microsoft Academic Search

    A. L Silva; R. A Costa; A. H Martins

    2003-01-01

    This work presents laboratory bench scale results for cyanide regeneration from pure alkaline aqueous solutions of gold, copper and iron cyanocomplexes using an innovative option of the AVR process associated to the ion exchange polymeric resins Imac HP555s® ((Room&Haas––USA) and Amberlite IRA-420® (Room&Haas Brasil Ltda.) in columns. The resin Imac HP555s® adsorbed 64.5% CN from the alkaline solution containing metal

  20. Ion exchange resins for the treatment of cyanidation tailings

    Microsoft Academic Search

    K. Fernando; F. Lucien; T. Tran; M. L. Carter

    2008-01-01

    Oxidative acid eluents comprising of H2O2 and H2SO4 have been proven to be effective in eluting base metal cyanide complexes from strong base resins. This study found that the repeated cycling between alkaline cyanide conditions and oxidative acid conditions does not affect the strong base or the total base capacity of strong base resins. However, it was found that a

  1. Elution of ion exchange resins by use of ultrasonication

    Microsoft Academic Search

    D Feng; C Aldrich

    2000-01-01

    The feasibility of using ultrasound to enhance the elution of three ion exchange resins was investigated. A laboratory-scale elution column immersed in an ultrasonic bath was used to investigate three elution systems. XAD7–Au (eluted with NaOH, at a pH of 10), IR120H–Cd (eluted with HCl) and A375–SO42? (eluted with saturated lime solutions). The physico-chemical stability of the resins was not

  2. CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN

    Microsoft Academic Search

    C. Nash; M. Duignan

    2010-01-01

    This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two 11 mL beds in

  3. Modification of (DGEBA) epoxy resin with maleated depolymerised natural rubber

    Microsoft Academic Search

    K. Dinesh Kumar; B. Kothandaraman

    2008-01-01

    In this work, diglycidyl ether of bisphenol A (DEGBA) type epoxy resin has been modified with maleated depolymerised natural rubber (MDPR). MDPR was prepared by grafting maleic anhydride onto depolymerised natural rub- ber. MDPR has been characterized by Fourier transform infrared (FT-IR) spectroscopy and nuclear magnetic resonance spectroscopy. MDPR was blended with epoxy resin at three different ratios (97\\/3, 98\\/2

  4. Characterisation of Epoxy Resins for Microstereolithographic Rapid Prototyping

    Microsoft Academic Search

    C. R. Chatwin; M. Farsari; S. Huang; M. I. Heywood; R. C. D. Young; P. M. Birch; F. Claret-Tournier; J. D. Richardson

    1999-01-01

    Two epoxy resins are investigated using non-degenerate fourwave mixing. The materials assessed are optimised for use with\\u000a a UV argon-ion laser. The holographic gratings were written at a wavelength of l= 351.1 nm for an irradiance range 0.5–3.0\\u000a W\\/cm 2 and read at l= 632.8 nm in order to compare the reactivity, curing speed, shrinkage and resolution of the resins.

  5. Benzoxazine resin/carbon nanotube nanostructured composite's degradation kinetic.

    PubMed

    Untem, Flávia O; Botelho, Edson C; Rezende, Mirabel C; Costa, Michelle Leali

    2014-07-01

    In the last decades a new class of thermoset phenolic resin is emerging as a substitute of the traditional epoxy and phenolic resins in the aircraft industry. This new class is called polybenzoxazines and its associates the epoxy resin's mechanical properties and phenolic resin's thermal and flame retardant properties, resulting in a resin with superior properties when analyzed with the others singly. The introduction of carbon nanotubes in low concentration into polymeric matrices can produce nanostructured materials with good properties. Thus, in this study, nanostructured composites of benzoxazine resin were processed with different concentration of carbon nanotubes (0.1%, 0.5% and 1.0% w/w). In order to evaluate the thermostability of the benzoxazine resin and its nanostructured composites, it was performed a degradation kinetic study using the thermogravimetric technique. For that, the analysis have been done with the temperature ranging from 25 degrees C to 1000 degrees C at nitrogen atmosphere (100 mL x min(-1)) and in different heating rates (2, 4, 6, 8, 10 and 20 degrees C x min(-1)), in order to obtain the kinetic parameters (activation energy, E(a), and pre-exponential factor, A), based on Ozawa-Wall-Flynn model. The results showed excellent agreement between the thermogravimetric curves obtained and the Ozawa-Wall-Flynn method. The degradation kinetic study showed that the introduction of carbon nanotubes in the benzoxazine matrix does not change the thermostability of the resin, so that it does not have a significant influence in the shelf life of the material. PMID:24757993

  6. Boron-modified phenolic resins for high performance applications

    Microsoft Academic Search

    Mohamed O. Abdalla; Adriane Ludwick; Temisha Mitchell

    2003-01-01

    A boron-modified phenolic resin (BPR) that flows at usable processing temperatures was prepared from the solvent-less reaction of triphenyl borate (TPB) and paraformaldehyde (PF). The reaction of TPB and PF was performed at three different resinifying temperatures, 130, 120 and 90 °C. The BPR produced at 90 °C melted upon reheating, which indicated promising processing applications for this resin. 1H

  7. Characterization and fractionation by ultrafiltration of guayule resin 

    E-print Network

    Daly, Monica Ann

    1989-01-01

    chromatography and infrared spectroscopy and to evaluate the feasibility of separating the resin according to molecular weight/size using ultrafiltration (UF). Identification and separation of potentially valuable fractions in the resin would increase... for further chemical analysis (in this case by infrared spectroscopy). GP C can also be used to determine molecular weight averages aud distributions for polydisperse systems. The excIusion column is calibrated by eluting appropriate calibration standards...

  8. High char imide-modified epoxy matrix resins

    NASA Technical Reports Server (NTRS)

    Serafini, T. T.; Delvigs, P.; Vannucci, R. D.

    1979-01-01

    Studies were performed to synthesize a novel class of bis (imide-amine) curing agents for epoxy matrix resins. Glass transition temperatures and char yield data of an epoxy cured with various bis (imide-amines) are presented. The room temperature and 350 F mechanical properties, and char yields of unidirectional graphite fiber laminates prepared with conventional epoxy and imide-modified epoxy resins are presented.

  9. Chemical composition of oleo-gum-resin from Ferula gummosa

    Microsoft Academic Search

    Hossein T. Jalali; Zahra J. Ebrahimian; Dmitry V. Evtuguin; Carlos Pascoal Neto

    2011-01-01

    The chemical composition of oleo-gum-resin from Ferula gummosa collected in the northern part of Iran has been studied. The fraction of oleo-gum-resin soluble in ethanol (ca 67wt.%) is composed by three major fractions: (i) monoterpenes and monoterpenoids (ca 15wt.% fraction), (ii) sesquiterpenes and sesquiterpenoids (ca 30wt.%) and (iii) triterpenes and triterpenoids (ca 55wt.%). The major families of terpenes and terpenoids

  10. Gamma radiation effect on gas production in anion exchange resins

    NASA Astrophysics Data System (ADS)

    Traboulsi, A.; Labed, V.; Dauvois, V.; Dupuy, N.; Rebufa, C.

    2013-10-01

    Radiation-induced decomposition of Amberlite IRA400 anion exchange resin in hydroxide form by gamma radiolysis has been studied at various doses in different atmospheres (anaerobic, anaerobic with liquid water, and aerobic). The effect of these parameters on the degradation of ion exchange resins is rarely investigated in the literature. We focused on the radiolysis gases produced by resin degradation. When the resin was irradiated under anaerobic conditions with liquid water, the liquid phase over the resin was also analyzed to identify any possible water-soluble products released by degradation of the resin. The main products released are trimethylamine (TMA), molecular hydrogen (H2g) and carbon dioxide (CO2g). TMA and H2g are produced in all the irradiation atmospheres. However, TMA was in gaseous form under anaerobic and aerobic conditions and in aqueous form in presence of liquid water. In the latter conditions, TMAaq was associated with aqueous dimethylamine (DMAaq), monomethylamine (MMAaq) and ammonia (NH). CO2g is formed in the presence of oxygen due to oxidation of organic compounds present in the system, in particular the degradation products such as TMAg.

  11. Effect of end group on novolak resin properties

    NASA Astrophysics Data System (ADS)

    Zampini, Anthony; Monaghan, Michael J.; Xu, Cheng-Bai; Cardin, William J.

    1998-06-01

    Model compounds formed by the reaction of m-cresol with 2,6- bis(hydroxymethyl)-p-cresol, DMPC, were isolated and characterized by 13C NMR. DMPC was found to couple at the 2, 4, and 6-positions of m-cresol at a rate of 12%, 34% and 54% respectively. The condensation reactions of m-cresol and DMPC with 2-hydroxy-3,5-dimethylbenzyl alcohol, 2-HDBA, or 4-hydroxy-3,5-dimethylbenzyl alcohol, 4-HDBA, were determined by 13C NMR to form novolak resins in a manner predicted by model compound data. The introduction of 2,4- dimethylphenol and 2,6-dimethylphenol as specific end-groups to novolak resins was demonstrated to affect both the resin dissolution and photoresist properties. Novolaks end-capped with the more highly o-o' coupled 2,4-dimethylphenol group have lower dissolution rates while the more p-p' coupled, intermolecular oriented, 2,6-dimethylphenol group show higher dissolution rates in TMAH. For the resins investigated, photoresist resolution properties appear to be dictated by the bulk resin structure. Photospeed, however, was greatly enhanced by the 2,6-dimethylphenol end-group. This knowledge was then applied towards the design of novolak resins having built-in dissolution and photospeed promoters, and a novolak/diazonaphthoquinone 0.25 micrometers capable i-line photoresist.

  12. Analysis of Tissue Reactions to Methacrylate Resin-based, Epoxy Resin-based, and Zinc Oxide–Eugenol Endodontic Sealers

    Microsoft Academic Search

    Roberta Kochenborger Scarparo; Fabiana Soares Grecca; Elaine Vianna Freitas Fachin

    2009-01-01

    The purpose of this study was to investigate the reaction of the subcutaneous connective tissue of rats to methacrylate resin-based sealer (EndoREZ), epoxy resin-based sealer (AH Plus), and zinc oxide–eugenol sealer (EndoFill). Polyethylene tubes containing the test materials were implanted in 18 rats. After 7, 30, and 60 days, tissues were collected for biopsy and fixed and processed for histologic

  13. Contributions of the network structure to the cure kinetics of epoxy resin systems according to the change of hardeners

    Microsoft Academic Search

    Whan Gun Kim; Jun Young Lee

    2002-01-01

    The cure kinetics of epoxy resin systems was investigated according to the change of curing agents, and analyzed in respect of the network structure. An autocatalytic cure reaction can be shown in the epoxy resin systems with phenol novolac hardener regardless of the kinds of epoxy resin and the epoxy resin systems using Xylok and dicyclopentadiene type phenol resin curing

  14. Methyl Jasmonate Induces Traumatic Resin Ducts, Terpenoid Resin Biosynthesis, and Terpenoid Accumulation in Developing Xylem of Norway Spruce Stems1

    PubMed Central

    Martin, Diane; Tholl, Dorothea; Gershenzon, Jonathan; Bohlmann, Jörg

    2002-01-01

    Norway spruce (Picea abies L. Karst) produces an oleoresin characterized by a diverse array of terpenoids, monoterpenoids, sesquiterpenoids, and diterpene resin acids that can protect conifers against potential herbivores and pathogens. Oleoresin accumulates constitutively in resin ducts in the cortex and phloem (bark) of Norway spruce stems. De novo formation of traumatic resin ducts (TDs) is observed in the developing secondary xylem (wood) after insect attack, fungal elicitation, and mechanical wounding. Here, we characterize the methyl jasmonate-induced formation of TDs in Norway spruce by microscopy, chemical analyses of resin composition, and assays of terpenoid biosynthetic enzymes. The response involves tissue-specific differentiation of TDs, terpenoid accumulation, and induction of enzyme activities of both prenyltransferases and terpene synthases in the developing xylem, a tissue that constitutively lacks axial resin ducts in spruce. The induction of a complex defense response in Norway spruce by methyl jasmonate application provides new avenues to evaluate the role of resin defenses for protection of conifers against destructive pests such as white pine weevils (Pissodes strobi), bark beetles (Coleoptera, Scolytidae), and insect-associated tree pathogens. PMID:12114556

  15. Organic polymeric matrix resins for composites

    SciTech Connect

    Arnold-McKenna, C.A. [White House Office of Science & Technology, Washington, DC (United States)

    1993-12-31

    This talk will highlight the basic chemistry of important representative polymeric matrices for composites and discuss some composite applications, particularly for advanced composites. The advanced composites market is primarily within the aerospace industry, with recreational, industrial, and automotive applications accounting for the remainder. As the large military component of the aerospace market declines, however, penetration into more cost-sensitive markets such as automotive and building and construction is important. Polymers that are used for composite applications may be either thermosetting or thermoplastic, and each offers advantages and disadvantages. Widespread use of thermoplastics, however, requires processability improvements. A major research thrust for thermosetting resins is to improve toughness; an important approach involves the incorporation of functionalized and non-functionalized thermoplastic additives, such as poly(arylene ether)s. A wide variety of technologies for polymeric composites are being explored in federal laboratories and the private sector. Some applications of these technologies include advanced aircraft, missiles, and spacecraft ; wind turbines; light-weight, tough aircraft and automobile structures; waste storage filter containers; and dental restorations and implants.

  16. Resinous binders for coal and chars

    SciTech Connect

    Olson, E.S.; Sharma, R.K.; Young, B.C. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-31

    Binder development and application to the briquetting or pelleting of coal fines has been extensive. The search for low-cost, effective binders for making strong and durable briquettes or pellets continues unabated. Strong, durable compacts are required, not only for handling, transport, and storage of the product but also to withstand the rigors of application such as flue gas treatment sorbents and catalytic supports. Many kinds of binders, organic and inorganic, have been used to gain the desired strength. Synthetic polymers have been investigated because they promote good strength and water insolubility, but these features are generally outweighed by the polymer cost. Promising earlier developments of biomass-derived binders have received slow market acceptance, mainly because of the cost resulting from the high concentrations required. However, recent advances in processing lignocellulosic materials have generated potentially low-cost polymeric binding agents for making coal briquettes. Phenol novolaks were previously used with lignites to make activated carbons. Recently, binders were prepared from mixtures of phenol, lignin, and formaldehyde and used for wood flour molding and friction materials. The goal of our work was to investigate the characteristics of resinous binders from lignocellulosic as well as coal-derived materials when used with dried or beneficiated coals and chars.

  17. Mechanical Properties of Degraded PMR-15 Resin

    NASA Technical Reports Server (NTRS)

    Tsuji, Luis C.

    2000-01-01

    Thermo-oxidative aging produces a nonuniform degradation state in PMR-15 resin. A surface layer, usually attributed to oxidative degradation, forms. This surface layer has different properties from the inner material. A set of material tests was designed to separate the properties of the oxidized surface layer from the properties of interior material. Test specimens were aged at 316 C in either air or nitrogen, for durations of up to 800 hr. The thickness of the oxidized surface layer in air aged specimens, and the shrinkage and coefficient of thermal expansion (CTE) of nitrogen aged specimens were measured directly. The nitrogen-aged specimens were assumed to have the same properties as the interior material in the air-aged specimens. Four-point-bend tests were performed to determine modulus of both the oxidized surface layer and the interior material. Bimaterial strip specimens consisting of oxidized surface material and unoxidized interior material were constructed and used to determine surface layer shrinkage and CTE. Results confirm that the surface layer and core materials have substantially different properties.

  18. Apparatus and method for removing solvent from carbon dioxide in resin recycling system

    DOEpatents

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2009-01-06

    A two-step resin recycling system and method solvent that produces essentially contaminant-free synthetic resin material. The system and method includes one or more solvent wash vessels to expose resin particles to a solvent, the solvent contacting the resin particles in the one or more solvent wash vessels to substantially remove contaminants on the resin particles. A separator is provided to separate the solvent from the resin particles after removal from the one or more solvent wash vessels. The resin particles are next exposed to carbon dioxide in a closed loop carbon dioxide system. The closed loop system includes a carbon dioxide vessel where the carbon dioxide is exposed to the resin, substantially removing any residual solvent remaining on the resin particles after separation. A separation vessel is also provided to separate the solvent from the solvent laden carbon dioxide. Both the carbon dioxide and the solvent are reused after separation in the separation vessel.

  19. Denitration of Rocky Flats Ion-Exchange Resins: Recommendation of Denitration Processes, October 19, 1995

    SciTech Connect

    Jacob Espinoza; Mary Barr; Wayne Smith

    1998-12-01

    Resin denitration via anion-exchange is an implementable process that can effectively mitigate the hazards associated with stored resins in which the bulk of the nitrate consists of an "exchangeable nitrate" ionically bound to the cationic sites of the anion-exchange resins. Salicylate has been selected as the exchange anion of choice because of its superior selectivity for the Rocky Flats resins and its unique potential for comprehensive recovery and recycle. This report outlines a single recommended resin denigration procedure that is reasonably independent of the resin composition and the current stored form. This procedure is not optimized but rather seeks to `over-treat' the resins so that a single procedure works for the variety of stored resins. The recommended treatment with sodium salicylate reduces resins by 95-99+% the measured exothermic behavior of the ion-exchange.

  20. Micromechanical properties of veneer luting resins after curing through ceramics.

    PubMed

    Oztürk, Elif; Hickel, Reinhard; Bolay, Sükran; Ilie, Nicoleta

    2012-02-01

    The aim of this study was to assess the performance of light-cured luting resin after curing under the ceramic restoration in comparison to dual-cured luting resin, by evaluating the micromechanical properties. Two hundred seventy thin luting composite films of ca. 170 ?m in thickness were prepared by using two light-cured luting resins (Variolink Veneer, Ivoclar Vivadent; RelyX Veneer, 3M ESPE) and a dual-cured luting resin (Variolink II, Ivoclar Vivadent). The composites were cured by using a LED-unit (Bluephase®, Ivoclar Vivadent) with three different curing times (10, 20, and 30 s) under two ceramics (IPS e.max Press, Ivoclar Vivadent; IPS Empress® CAD, Ivoclar Vivadent) of different thicknesses (0, 0.75, and 2 mm). Forty-five groups were included, each containing six thin films. The samples were stored after curing for 24 h at 37°C by maintaining moisture conditions with distilled water. Micromechanical properties of the composites were measured with an automatic microhardness indenter (Fisherscope H100C, Germany). For each sample, ten indentations were made, thus totalizing 60 measurements per group. Micromechanical properties of the luting resins were statistically analyzed (SPSS 17.0). Significant differences were observed between the micromechanical properties of the luting resins (p < 0.05). Variolink II showed the highest values in modulus of elasticity (E = 11 ± 0.5)* and Vickers hardness (HV = 48.2 ± 3.2)* and the lowest values in creep (Cr = 4.3 ± 0.1)* and elastic-plastic deformation (We/Wtot = 38.6 ± 0.7)* followed by RelyX Veneer (E = 6.9 ± 0.3, HV = 33 ± 2.5, Cr = 4.6 ± 0.2, We/Wtot = 41.8 ± 1.0)* and Variolink Veneer (E = 4.4 ± 0.4, HV = 20.1 ± 2.6, Cr = 5 ± 0.2, We/Wtot = 43.7 ± 1.3)*. Dual-cured luting resin expressed higher values in the micro-mechanical properties compared to the light-cured luting resins. The effect of luting resin type on the micromechanical properties of the luting resins was higher than the effect of curing time, ceramic type and ceramic thickness respectively (*The values of reference without ceramics for 30 s curing time). PMID:21057833