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1

LAB STUDY ON REGENERATION OF SPENT DOWEX 21K 16-20 MESH ION EXCHANGE RESIN  

SciTech Connect

Currently the effort to remove chromate from groundwater in the 100K and 100H Areas uses DOWEX 21K 16-20. This report addresses the procedure and results of a laboratory study for regeneration of the spent resin by sodium hydroxide, sulfuric acid, or sodium sulfate to determine if onsite regeneration by the Effluent Treatment Facility is a feasible option.

DUNCAN, J.B.

2007-01-24

2

Photodecomposition of dichloromethane catalyzed by tetrachloroferrate(III) supported on a Dowex anion exchange resin.  

PubMed

The FeCl4(-) ion, heterogenized on a Dowex ion exchange resin, catalyzes the aerobic photodecomposition of neat CH2Cl2. Phosgene production was used to characterize the extent of decomposition, although it appears to be a secondary product from the decomposition of chloroform, which is suggested to arise from the reaction of dichloromethanol with hydrogen chloride. The yield of CHCl3 increases when the production of phosgene is suppressed by water or acetonitrile. CuCl4(2-), likewise heterogenized on Dowex, is photocatalytically inactive. PMID:23753006

Chan, Alissa M; Harvey, Brent M; Hoggard, Patrick E

2013-09-01

3

FB-Line resin testing final report  

SciTech Connect

The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer's specified ionic type and form, and the Dowex 50W resins have characteristic water retention capacities. These tests conclude that the ion exchange resins in use in FB-Line meet the approved safety document criteria for cross-linking, ionic form, and resin type.

Bannochie, C.J.

1992-01-23

4

FB-Line resin testing final report  

Microsoft Academic Search

The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer`s specified ionic type and form,

Bannochie

1992-01-01

5

FB-Line resin testing final report  

Microsoft Academic Search

The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer's specified ionic type and form,

Bannochie

1992-01-01

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

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.

Mosley, W.C.

2001-09-17

7

Preparation and in vitro release of dual-drug resinates containing equivalent content dextromethorphan and diphenhydramine.  

PubMed

The dual-drug resinate containing equivalent content of dextromethorphan hydrobromide (DTM) and diphenhydramine hydrochloride (DPH) was developed and characterized. To achieve this specific resinate, a procedure of simultaneous dual-drug loading using loading solutions composed of different proportions of DTM and DPH was performed and a dual-drug loading diagram was constructed to determine the equivalent drug loading solution (ELS) and also the estimated equivalent drug content (EQC). The effects of resin crosslinkage, overall drug concentration of the loading solution, and temperature during drug loading on the values of ELS and EQC were assessed. The increased overall drug concentration from 0.25 to 1.0% w/v elevated the EQC values from 18 to 35% w/w for low crosslinked resins (Dowex 50 W x 2 and x 4), and from 18 to 27% w/w for high crosslinked resin (Dowex 50 W x 8). It also changed the values of ELS from 0.50 to 0.48 for the low crosslinked resins, and 0.50 to 0.55 for the high crosslinked resin. For the high crosslinked resin, the applied heat from 35 to 65 degrees C further increased the values of EQC from 27 to 32% w/w, and changed the values of ELS in the reverse direction from 0.55 to 0.48. However, the heat did not exert significant effects on the values of EQC and ELS for the low crosslinked resins. Different batches of dual-drug resinates prepared from the determined ELS provided the resultant resinates with equivalent contents of DTM and DPH which were very close to the estimated EQC. The drug release from the resinates was performed in 0.05, 0.1, 0.2, and 0.4 N of KCl solutions. The increased ionic strength generally accelerated the release of both drugs except for 0.4 N KCl solution in which the drug release from the resinates of high crosslinkage was decreased. The congestion on the outward movement of drugs through the high crosslinked matrix might cause the delay of drug release. In conclusion, the release study demonstrated that the dual-drug resinate using a suitable crosslinked resin could be used for extended delivery of two combined drugs with the equivalent therapeutic dose. PMID:16638687

Akkaramongkolporn, Prasert; Kulvanich, Poj; Pathipvanich, Mitr

2006-04-01

8

Uranium Adsorption on Ion-Exchange Resins - Batch Testing  

SciTech Connect

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.

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

2010-12-01

9

Luminol chemiluminescence in unbuffered solutions with a cobalt(II)-ethanolamine complex immobilized on resin as catalyst and its application to analysis.  

PubMed

Using a heterogeneous catalyst, Co(II)-ethanolamine complex sorbed on Dowex-50W resin, the chemiluminescence (CL) of luminol in unbuffered or weakly acidic solution was studied in the presence of H2O2. The maximum luminol CL wavelength at pH 5.7 was 448 nm, 23 nm longer than that in a basic solution (pH 10.5). Three different ligands, mono-, di-, and triethanolamine, and six transition metal ions, Co(II), Cu(II), Ni(II), Mn-(II), Fe(II), and Fe(III) were compared by CL measurements. The CL intensity decreased in the order mono- > di- > triethanolamine and Co(II) > Cu(II) > Ni(II) > Fe-(III) > Mn(II) > Fe(II). This heterogeneous CL system was developed as H2O2 and glucose flow-through sensors. Detection limits (S/N = 3) of H2O2 and glucose using Dowex-50W-X4-Co(II)-monoethanolamine as catalyst are 1 x 10(-7) M and 1 x 10(-6) M, respectively. On the basis of the studies of the CL, fluorescence, UV-vis and ESCA spectra and the effect of dissolved oxygen in luminol solution, a mechanism for CL emission in unbuffered solution was considered as the formation of a superoxide radical ion during the decomposition of H2O2 catalyzed by the Co(II)-ethanolamine immobilized resin. Then the superoxide radical ion acted on luminol and the CL was emitted. The applications of the proposed method to determine H2O2 in rainwater without any special pretreatment and glucose in human urine and orange juice samples give satisfactory results. PMID:11721898

Lin, J M; Shan, X; Hanaoka, S; Yamada, M

2001-11-01

10

Preparation of curium-americium oxide microspheres by resin-bead loading  

SciTech Connect

Resin-bead loading and calcination techniques have been used to produce all curium and americium oxide feed material (about 2.2 kg) for HFIR targets since 1971. The process based on Dowex 50W resin has progressed from a series of test runs, through special production runs, into routine production in permanent equipment beginning in 1975. Key attributes of this process are its reliability, high yields, and ease of operation. The process is suited for remote operation in hot cells. Yields approaching 95% are routinely obtained and only one unacceptable product has been generated during routine production operations. There have been no problems in fabricating targets from this oxide or in the subsequent irradiation of these targets. The present scale of production of 150 to 250 g/y supplies the present need and is comparable with the level of other chemical process operations at TRU. Since the annual production is accomplished in two 8 to 12 day periods, there has been no reason to consider further scale-up. However, the rate of production could easily be doubled by simply adding a second set of calcination equipment.

Chattin, F.R.; Benker, D.E.; Lloyd, M.H.; Orr, P.B.; Ross, R.G.; Wiggins, J.T.

1980-01-01

11

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

Microsoft Academic Search

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

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

2009-01-01

12

Adsorption and desorption characteristics of nucleotide based coenzymes on agarose encapsulated resins for long term cofactor supply of enzymatic reactions.  

PubMed

In order to find optimal long term cofactor supply for continuous enzymatic detoxification processes, different resins of varying surface, dipole moment, pore size, and chemical structure were investigated for their adsorptive capacity as well as their desorption behaviour towards various nucleotide based coenzymes. UDPGA, NADPGH, NADH, and SAM were gently shaken with agarose coated resins XAD-12, XAD-8, XAD-7, XAD-4, XAD-2, Dowex 1 X 2 (50-100; 200-400), Dowex 1 X 4 (20-50; 200-400), Dowex 2 X 8, and charcoal until all nucleotide was adsorbed or a saturation of the resins was achieved. High adsorption capacity was not always found to correlate with a steady release of cofactor in desorption experiments. Under this premise the optimal resin-cofactor combinations for long term cofactor supply were found to be XAD-12 for UDPGA, Dowex 2 X 8 for NADPH, Dowex 1 X 4 (20-50) for NADH, and XAD-7 for SAM. PMID:4055098

Brunner, G; Tegtmeier, F; Lösgen, H

1985-07-01

13

An air-cooled pulse tube cryocooler with 50 W cooling capacity at 77 K  

NASA Astrophysics Data System (ADS)

A pulse tube cryocooler with 50 W cooling capacity at 77 K is developed to cool superconducting devices mounted on automobiles. The envisioned cryocooler weight is less than 40 kg, and the input electric power is less than 1 kW. To achieve these requirements, the working frequency is increased to 75 Hz, and the dual-opposed pistons use gas bearings to reduce compressor weight and volume. The heat from the main heat exchanger is rejected by forced convective air instead of water. The compressor and the cold finger are carefully matched to improve the efficiency. The details of these will be presented in this paper. After some adjustment, a no load temperature for the pulse tube cryocooler of 40 K was achieved with 1 kW input electric power in surroundings at 298 K. At 77 K, the cooling capacity is 50 W. If the main heat exchanger is cooled by water at 293 K, the cooling capacity increases to 64 W, corresponding to a relative Carnot efficiency of 18%.

Hu, Jianying; Wang, Xiaotao; Zhu, Jian; Chen, Shuai; Luo, Ercang; Li, Haibin

2014-01-01

14

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

SciTech Connect

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.

Serkiz, S.M.

2000-09-05

15

Distribution coefficients of 52 elements on a strongly basic anion-exchange resin in aqueous solutions of orthophosphoric acid  

Microsoft Academic Search

BS>Preliminary results of the systematic determination of the ; distribution coefficients of 52 elements on Dowex 1-X8 resin in HâPOâ ; solutions at concentrations from 0.1 to 14 M at room temperature are reported. ; Adsorbabilities of elements show marked differences even for elements in the same ; group of the Periodic Table. With few exceptions the distribution coefficients ;

H. Polkowska-Motrenko; R. Dybczynski

1974-01-01

16

Performance of selected anion exchange resins for the treatment of a high DOC content surface water.  

PubMed

The objective of this study was first to compare the performance of four strong anion exchange resins (AERs) (MIEX from Orica Pty Ltd, DOWEX-11 and DOWEX-MSA from DOW chemical and IRA-938 from Rohm and Haas) for their application in drinking water treatment (natural organic matter (NOM), mineral anions (nitrate, sulfate and bromide) and pesticide removal) using bench-scale experimental procedures on a high DOC content surface water. The efficiency of MIEX for NOM and mineral anions removal was furthermore evaluated using bench-scale dose-response experiments on raw, clarified and post-ozonated waters. NOM removal was assessed using the measurement of dissolved organic carbon (DOC), UV absorbance at 254 nm (UV254) and the use of high-performance size exclusion chromatography with UV (HPSEC/UV) and fluorescence detection (HPSEC/FLUO). The MIEX and IRA938 anionic resins exhibit a faster removal of NOM and mineral anions compared to the DOWEX11 and MSA AERs. All the resins were found to be very effective with similar performances after 30 to 45 min of contact time. As expected, only limited sorption of atrazine and isoproturon (C0=1 microg/L) occurred with MIEX, DOWEX11 and MSA AERs. MIEX resin proved to be very efficient in eliminating NOM of high-molecular weight but also a large part of the smallest UV absorbing organic compounds which were refractory to coagulation/flocculation treatment. Remaining DOC levels after 30 min of contact with MIEX were found similar in raw water, clarified water and even post-ozonated water implying no DOC benefit can be gained by employing conventional treatment prior to MIEX treatment. Removal of bromide (initial concentration 110 microg/L) was also observed and ranged from 30% to 65% for resin dose increasing from 2 to 8 mL/L. T PMID:15899268

Humbert, Hugues; Gallard, Hervé; Suty, Hervé; Croué, Jean-Philippe

2005-05-01

17

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

SciTech Connect

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.

Marsh, S.F.

1990-11-01

18

Removal of aluminum(III)-based turbidity in water using hydrous titanium oxide dispersed in ion-exchange resins  

SciTech Connect

An adsorber consisting of hydrous titanium oxide (HTiO) dispersed in a Dowex-type ion-exchange resin matrix (designated RT resins) has been developed which is capable of removing Al(III)-based colloidal dispersions in the neutral pH condition. The effect of resin crosslinking, particle size, HTiO loading, turbidity level, and flow rate on the turbidity removal efficiency of RT resins has been studied. It is demonstrated that a train of columns comprising RT resin, H/sup +/, and OH/sup -/ form of resins could be used for large-scale purification operations at high flow rates. These columns, apart from removing turbidity and associated radioactivity, can effectively remove dissolved uranium present in ppb levels when used for water purification in nuclear reactors.

Venkataramani, B.; Karweer, S.B.; Iyer, R.K.; Phatak, G.M.; Iyer, R.M.

1988-04-01

19

Separation and Removal of Mercury(II) from Water Samples Using (Acetylacetone)?2?Thiol?Phenyleneimine Immobilized on Anion?Exchange Resin Prior to Determination by Cold Vapor Inductively Coupled Plasma Atomic Emission Spectroscopy  

Microsoft Academic Search

(Acetylacetone)?2?thiol?phenyleneimine (H2L) immobilized on an anion?exchange resin (Dowex) was used for separation and removal of mercury from natural water samples and for preconcentration prior to its determination by cold vapor inductively coupled plasma atomic emission spectroscopy. The metal was eluted from the column using a solution of 10% thiourea in 0.1 M HCl. The modified resin is higly selective with an

Derya Kara

2005-01-01

20

Uranium Removal from Contaminated Groundwater by Synthetic Resins  

SciTech Connect

Synthetic resins are shown to be effective in removing uranium from contaminated groundwater. Batch and field column tests showed that strong-base anion-exchange resins were more effective in removing uranium from both near-neutral-pH (6.5)- and high-pH (8)-low-nitrate-containing ground waters, than metal-chelating resins, which removed more uranium from acidic-pH (5)-high-nitrate-containing groundwater from the Oak Ridge Reservation (ORR) Y-12 S-3 Ponds area in Tennessee, USA. Dowex 1-X8 and Purolite A-520E anion-exchange resins removed more uranium from high-pH (8)-low-nitrate-containing synthetic groundwater in batch tests than metal-chelating resins. The Dowex{trademark} 21K anion-exchange resin achieved a cumulative loading capacity of 49.8 mg g{sup -1} before breakthrough in a field column test using near-neutral-pH (6.5)-low-nitrate-containing groundwater. However, in an acidic-pH (5)-high-nitrate-containing groundwater, metal-chelating resins Diphonix and Chelex-100 removed more uranium than anion-exchange resins. In 15 mL of acidic-pH (5)-high-nitrate-containing groundwater spiked with 20 mg L{sup -1} uranium, the uranium concentrations ranged from 0.95 mg L{sup -1} at 1-h equilibrium to 0.08 mg L{sup -1} at 24-h equilibrium for Diphonix and 0.17 mg L{sup -1} at 1-h equilibrium to 0.03 mg L{sup -1} at 24-h equilibrium for Chelex-100. Chelex-100 removed more uranium in the first 10 min in the 100 mL of acidic-(pH 5)-high-nitrate-containing groundwater (5 mg L{sup -1} uranium); however, after 10 min, Diphonix equaled or out-performed Chelex-100. This study presents an improved understanding of the selectivity and sorption kinetics of a range of ion-exchange resins that remove uranium from both low- and high-nitrate-containing groundwaters with varying pHs.

Phillips, Debra H. [Queen's University, Belfast; Gu, Baohua [ORNL; Watson, David B [ORNL; Parmele, C. S. [Science Applications International Corporation (SAIC), Oak Ridge, TN

2008-01-01

21

Determination of Pb(II) by Photoacoustic Spectroscopy with a Solid-Phase Spectrophotometry Approach Using 2-(2-Thiazolylazo)--cresol (TAC) Coated on Resin  

NASA Astrophysics Data System (ADS)

In this study, preliminary results obtained for Pb(II) determination by photoacoustic spectroscopy are introduced. It is based on an amplitude measurement of a photoacoustic signal obtained from a Pb(II) complex formation with2-(2-thiazolylazo)- p-cresol (TAC) retained in an anionic resin such as Dowex 1X8. The Pb(II)-TAC complex spectrum reveals an absorption band, which is assigned to a Pb(II)-TAC complex retained on the resin. The peak height of this band is proportional to the Pb(II) concentration, and it can be used to obtain quantitative information of the metal content.

Saavedra, R.; Gómez, R.; Soto, C.; Aguayo, D.; Candia, C.; Yañez, J.; Zuñiga, V.

2013-09-01

22

Resin hybrid composite laminates  

SciTech Connect

Hybrid composites are generally referred to as the materials that combine two or more fibers in a suitable binding resin. Resin hybrid composites described in this paper utilize two or more resins with a suitable reinforcement. The resins are rigid resin and flexible resins. The elongation of the rigid resin is less than 2% and elongation of the flexible resins are varied between 25% to 100% by blending a very flexible resin with the rigid resin. Test laminates are fabricated by using either glass, carbon or aramid reinforcement in a layered sequence. This produces rigid-flexible-rigid and flexible-rigid-flexible laminates. These laminates are tested for impact, compression, flexural and inter-laminar strengths. Results show that the resin hybriding provides a wide choice of mechanical properties to the composite industry.

Bhatnagar, A.

1986-01-01

23

Photocatalysis of Chloroform Decomposition by Tetrachlorocuprate (II) on Dowex 2-X8.  

PubMed

Heterogenized on a polystyrene anion exchange resin and in the presence of oxygen, CuCl42- 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 CuCl42--catalyzed photodissociation of CCl4 , yielding phosgene with CCl3 radicals as chain carriers. Photodecomposition is retarded by added Cl(-) , CH3 CN, C6 H12 or C2 H5 OH, 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

Harvey, Brent M; Hoggard, Patrick E

2014-11-01

24

Resin processing system  

SciTech Connect

This patent describes a resin processing system for use in chemical decontamination of nuclear reactor primary systems. It comprises a fresh resin supply tank; a batching tank; a fresh resin pump connected to the fresh resin supply tank and the batching tank; a plurality of demineralizers wherein process fluids are demineralized; a resin feed pump connected to the batching tank capable of transporting fresh resin from the batching tank; a movable connection means connecting the resin feed pump to one of the plurality of demineralizers; a sluice water supply tank; a sluice water pump connected to the sluice water supply tank and the plurality of demineralizers; a spent resin storage tank connected to each of the plurality of demineralizers; a recycle pump connected to an outlet of the spent resin storage tank and having a pump outlet connected to the sluice water supply tank; and a screen at the outlet of the spent resin storage tank to retain spent resin within the spent resin storage tank while allowing sluice water to be recycled.

Corpora, G.J.; Schlonski, J.S.; Miller, P.E.; Bauer, F.I.

1992-08-18

25

Polyester Resin Hazards  

PubMed Central

Polyester resins are being increasingly used in industry. These resins require the addition of catalysts and accelerators. The handling of polyester resin system materials may give rise to skin irritations, allergic reactions, and burns. The burns are probably due to styrene and organic peroxides. Atmospheric pollution from styrene and explosion and fire risks from organic peroxides must be prevented. Where dimethylaniline is used scrupulous cleanliness and no-touch technique must be enforced. Handling precautions are suggested. Images PMID:14014495

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

1963-01-01

26

Delayed cure bismaleimide resins  

DOEpatents

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)

Not Available

1982-08-12

27

IRRADIATED PETROLEUM RESINS  

Microsoft Academic Search

A method for improving the properties of polymeric material produced by ; the Friedel-Crafts polymerization of light, cracked petroleum fractions is ; presented. The petroleum resins are mixed with a divinyl aromatic and irradiated ; at a dose rate of at least 0.1 equivalent Mr\\/hr until at least 1\\/2 equivalent Mr ; is absorbed. Resinous solids are obtained that have

J. E. Shewmaker; J. F. Nelson

1963-01-01

28

Biocompatibility of composite resins  

PubMed Central

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

Mousavinasab, Sayed Mostafa

2011-01-01

29

Guayule resin separation and purification  

E-print Network

to investigate economic viability. The composition of the resin is only partially known. A substantial portion, about 44%, of the resin remains uncharacterized. This uncharacterized portion is of low volatility (5). The characterized portion consists... resin chromatography most of the mass elutes in the 2nd fraction. This is possibly so because of the difference in composition of the two resins. 30 Table 2. Column chromatography of xylene resins over basic alumina Fraction Eluting solvent hexane...

Bajwa, Mohinder P.S.

2012-06-07

30

40 CFR 414.50 - Applicability; description of the thermosetting resins subcategory.  

...Ketone-Formaldehyde Resins *Melamine Resins *Phenolic Resins *Polyacetal Resins Polyacrylamide *Polyurethane Prepolymers *Polyurethane Resins *Urea Formaldehyde Resins *Urea Resins [52 FR 42568, Nov. 5, 1987, as amended...

2014-07-01

31

Graphite fiber reinforced thermoplastic resins  

NASA Technical Reports Server (NTRS)

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.

Novak, R. C.

1975-01-01

32

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

USGS Publications Warehouse

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.

Szabo, B. J.; Joensuu, O.

1967-01-01

33

Method for removing contaminants from plastic resin  

DOEpatents

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.

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

2008-12-09

34

Retrofit for Plastic Resin Driers  

E-print Network

RETROFIT FOR PLASTIC RESIN DRIERS BABU JOSEPH PH.D. Supervising Engineer Southern California Edison Company, Irwindale, California GEORGE THURO Thuro, & Associates, Costa Mesa, California Plastic resins used in injection molding have... FOR PLASTIC RESIN DRIERS BABU JOSEPH PH.D. Supervising Engineer Southern California Edison Company, Irwindale, California GEORGE THURO Thuro, & Associates, Costa Mesa, California Plastic resins used in injection molding have to be dried to specified levels...

Joseph, B.; Thuro, G.

35

Production of petroleum polymer resins  

Microsoft Academic Search

In other countries, petroleum polymer resins are being used successfully in large volumes. In the U.S. in 1982, for example, 128,000 tonnes of petroleum polymer resins were produced [2], much of which was used in the paint and varnish industry. In commercial production in the USSR are a dark-colored styrene-lndene resin and light-colored petroleum polymer resins of two types --

Yu. V. Dumskii; M. E. Belyakov; A. K. Suroto; G. F. Cherednikova; L. B. Grin'ko

1988-01-01

36

Powdered resin for condensate polishing  

Microsoft Academic Search

Powdered resin systems have a lot to offer in the deionization of low TDS waters, as can be seen in the wide use of this process for the treatment of condensate in the electric power industry. I believe that as new ion-exchange resins are developed, we will see the powdered ion-exchange resin process adopted in other industries. At this time,

Richard Hetherington

1997-01-01

37

Resin impregnation process for producing a resin-fiber composite  

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

38

Production of petroleum polymer resins  

SciTech Connect

A dark-colored styrene-indene resin and light-colored petroleum polymer resins of two types- SPP and Piroplast-2 are in commercial production in the Soviet Union. The raw material for the production of the dark-colored styrene-indene resin is heavy pyrolysis tar which is a residue from the distillation of liquid byproducts obtained in pyrolysis. The flow plans for the continuous production of SPP resin and Piroplast-2 are described. These resins are low cost materials as the original raw material is inexpensive and the production costs are low.

Dumskii, Yu.V.; Belyakov, M.E.; Suroto, A.K.; Cherednikova, G.F.; Grin'ko, L.B.

1988-09-01

39

Flame Retardant Epoxy Resins  

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

40

Phenoxy resins containing pendent ethynyl groups and cured resins therefrom  

SciTech Connect

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

Hergenrother, P.M.

1984-05-01

41

Functional polycyclopentadiene resins via hydroboration process  

Microsoft Academic Search

This patent describes a process for preparing a functionalized petroleum resin. It comprises dissolving a petroleum resin in a solvent to form a solution, the resin being formed by polymerizing feeds containing cyclopentadiene, dicyclopentadiene and alkyl derivatives thereof, the resin having a norbornene moiety with a double bond; adding to the solution a borane, reacting the petroleum resin with the

T. C. Chung; E. Berluche; J. Bock; R. V. Kastrup

1992-01-01

42

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2012 CFR

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2012-04-01

43

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2013 CFR

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2013-04-01

44

21 CFR 178.3930 - Terpene resins.  

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2014-04-01

45

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2011 CFR

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2011-04-01

46

Imide modified epoxy matrix resins  

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

47

Processable High Temperature Laminating Resins.  

National Technical Information Service (NTIS)

P13N Polyimide Resin was modified to provide autoclave moldability for boron monofilament and graphite fiber prepregs and to improve the thermo-oxidative stability of composites. It was shown that a modified P13N resin provided autoclave molded boron and ...

R. W. Vaughan, R. J. Jones

1971-01-01

48

Chromatography resin support  

DOEpatents

An apparatus and method of using an improved chromatography resin support is disclosed. The chromatography support platform is provided by a stainless steel hollow cylinder adapted for being inserted into a chromatography column. An exterior wall of the stainless steel cylinder defines a groove for carrying therein an "O"-ring. The upper surface of the stainless steel column is covered by a fine stainless steel mesh welded to the edges of the stainless steel cylinder. When placed upon a receiving ledge defined within a chromatography column, the "O"-ring provides a fluid tight seal with the inner edge wall of the chromatography cylinder. The stainless steel mesh supports the chromatography matrix and provides a back flushable support which is economical and simple to construct.

Dobos, James G. (North Augusta, SC)

2002-01-01

49

Resin reinforced expansion anchor system  

SciTech Connect

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.

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

1988-08-16

50

Grafted methylenediphosphonate ion exchange resins  

DOEpatents

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 phosphorous. The pendent groups have the formula ##STR1## 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.

Trochimcznk, Andrzej W. (Knoxville, TN); Gatrone, Ralph C. (Plymouth, PA); Alexandratos, Spiro (Knoxville, TN); Horwitz, E. Philip (Naperville, IL)

1998-01-27

51

Grafted methylenediphosphonate ion exchange resins  

DOEpatents

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 phosphorous. The pendent groups have the formula ##STR1## 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.

Trochimcznk, Andrzej W. (Knoxbille, TN); Gatrone, Ralph C. (Plymouth, PA); Alexandratos, Spiro (Knoxville, TN); Horwitz, E. Philip (Naperville, IL)

1997-01-01

52

Resin/graphite fiber composites  

NASA Technical Reports Server (NTRS)

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.

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

1972-01-01

53

Petroleum resins and their production  

Microsoft Academic Search

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°C. to about 120°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

Luvinh

1989-01-01

54

Microtensile bond strength of composite resin to glass-infiltrated alumina composite conditioned with Er,Cr:YSGG laser.  

PubMed

Tribochemical silica-coating is the recommended conditioning method for improving glass-infiltrated alumina composite adhesion to resin cement. High-intensity lasers have been considered as an alternative for this purpose. This study evaluated the morphological effects of Er,Cr:YSGG laser irradiation on aluminous ceramic, and verified the microtensile bond strength of composite resin to ceramic following silica coating or laser irradiation. In-Ceram Alumina ceramic blocks were polished, submitted to airborne particle abrasion (110 ?m Al(2)O(3)), and conditioned with: (CG) tribochemical silica coating (110 ?m SiO(2)) + silanization (control group); (L1-L10) Er,Cr:YSGG laser (2.78 ?m, 20 Hz, 0.5 to 5.0 W) + silanization. Composite resin blocks were cemented to the ceramic blocks with resin cement. These sets were stored in 37°C distilled water (24 h), embedded in acrylic resin, and sectioned to produce bar specimens that were submitted to microtensile testing. Bond strength values (MPa) were statistically analyzed (? ?0.05), and failure modes were determined. Additional ceramic blocks were conditioned for qualitative analysis of the topography under SEM. There were no significant differences among silicatization and laser treatments (p > 0.05). Microtensile bond strength ranged from 19.2 to 27.9 MPa, and coefficients of variation ranged from 30 to 55%. Mixed failure of adhesive interface was predominant in all groups (75-96%). No chromatic alteration, cracks or melting were observed after laser irradiation with all parameters tested. Surface conditioning of glass-infiltrated alumina composite with Er,Cr:YSGG laser should be considered an innovative alternative for promoting adhesion of ceramics to resin cement, since it resulted in similar bond strength values compared to the tribochemical treatment. PMID:20737182

Eduardo, Carlos de Paula; Bello-Silva, Marina Stella; Moretto, Simone Gonçalves; Cesar, Paulo Francisco; de Freitas, Patricia Moreira

2012-01-01

55

Maleimide Functionalized Siloxane Resins  

SciTech Connect

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).

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

1999-04-01

56

Functional polycyclopentadiene resins via hydroboration process  

SciTech Connect

This patent describes a process for preparing a functionalized petroleum resin. It comprises dissolving a petroleum resin in a solvent to form a solution, the resin being formed by polymerizing feeds containing cyclopentadiene, dicyclopentadiene and alkyl derivatives thereof, the resin having a norbornene moiety with a double bond; adding to the solution a borane, reacting the petroleum resin with the borane compound at about room temperature for a sufficient period of time to form a derivative of the petroleum resin containing a borane group; and reacting the derivative of the petroleum resin with a chemical agent capable of replacing the borane group of the petroleum resin derivative with a functional group, thereby converting the derivative into the functionalized petroleum resin.

Chung, T.C.; Berluche, E.; Bock, J.; Kastrup, R.V.

1992-03-03

57

Disposal of bead ion exchange resin wastes  

SciTech Connect

Bead ion exchange resin wastes are disposed of by a process which involves spray-drying a bead ion exchange resin waste in order to remove substantially all of the water present in such waste, including the water on the surface of the ion exchange resin beads and the water inside the ion exchange resin beads. The resulting dried ion exchange resin beads can then be solidified in a suitable solid matrix-forming material, such as a polymer, which solidifies to contain the dried ion exchange resin beads in a solid monolith suitable for disposal by burial or other conventional means.

Gay, R.L.; Granthan, L.F.

1985-12-17

58

Phosphonic acid based ion exchange resins  

DOEpatents

An ion exchange resin is described for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene. 10 figs.

Horwitz, E.P.; Alexandratos, S.D.; Gatrone, R.C.; Chiarizia, R.

1996-07-23

59

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2011 CFR

...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...

2011-04-01

60

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2010 CFR

...isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified in paragraph...conditions. (a) The resins are produced by the condensation of xylene-formaldehyde resin and 4,4?-isopropylidenediphenol-epichlorohydrin...di-, or trimethylol phenol and capryl alcohol...

2010-04-01

61

Improved Fire-Resistant Resins for Laminates  

NASA Technical Reports Server (NTRS)

Fire-resistant resins for fabricating laminates with inorganic fibers, especially graphite fibers, are formed from bisimides containing main-chain phosphorus and olefinic end groups. Bisimides are thermally polymerized to form resins and laminates virtually imcombustible in pure oxygen at 300 degrees C. New resins are suitable for many applications requiring good adhesion and excellent resistance to heat, fire, solvents and chemicals.

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

1982-01-01

62

Glycoprotein Enrichment Resin User Manual  

E-print Network

buffer containing either Tris or sorbitol. Specific Enrichment of Glycoproteins Glycoprotein Enrichment Enrichment Resin· Other User Manual (PT4050-1)· Visit our Protein Expression and Purification product pages at www.clontech.com for a current list of products available for protein research. #12;Glycoprotein

Lebendiker, Mario

63

Color Improvement of Petroleum Resin \\  

Microsoft Academic Search

A reaction of thermal-cracked higher fractions obtained from petroleum naptha with maleic anhydride gives a raw material affording a lighter color petroleum resin of 6 G than ordinarily produced one of 11 to 12 G, measured by Gardner scale. Then, some color components which were not yet reported, removed by the reaction, have been identified from the reaction products to

Yoshiyuki Iwase

1979-01-01

64

SPECTROSCOPIC STUDIES OF PETROLEUM RESINS  

Microsoft Academic Search

Resin fractions containing heteroatoms obtained from deasphaltened oils of petroleum residues (500C+) of Bombay High 7lpar;BH) and Gujrat Crude Mix (GCM) have been separated into acidic, basic and neutral Lewis base (NLB) types employing chromatographic methods. Ultimate compositions of these fractions have been determined for deducing the average molecular formulae. Infrared spectroscopy has been employed for assigning various heteroatomic functional

S. L. S. Sarowha; I. D. Singh

1988-01-01

65

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

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

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

2014-03-01

66

Petroleum resins and their production  

SciTech Connect

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.

Luvinh, Q.

1989-04-25

67

Pharmaceutical Applications of Ion-Exchange Resins  

NASA Astrophysics Data System (ADS)

The historical uses of ion-exchange resins and a summary of the basic chemical principles involved in the ion-exchange process are discussed. Specific applications of ion-exchange resins are provided. The utility of these agents to stabilize drugs are evaluated. Commonly occurring chemical and physical incompatibilities are reviewed. Ion-exchange resins have found applicability as inactive pharmaceutical constituents, particularly as disintegrants (inactive tablet ingredient whose function is to rapidly disrupt the tablet matrix on contact with gastric fluid). One of the more elegant approaches to improving palatability of ionizable drugs is the use of ion-exchange resins as taste-masking agents. The selection, optimization of drug:resin ratio and particle size, together with a review of scaleup of typical manufacturing processes for taste-masked products are provided. Ion-exchange resins have been extensively utilized in oral sustained-release products. The selection, optimization of drug:resin ratio and particle size, together with a summary of commonly occurring commercial sustained-release products are discussed. Ion-exchange resins have also been used in topical products for local application to the skin, including those where drug flux is controlled by a differential electrical current (ionotophoretic delivery). General applicability of ion-exchange resins, including ophthalmic delivery, nasal delivery, use as drugs in their own right (e.g., colestyramine, formerly referred to as cholestyramine), as well as measuring gastrointestinal transit times, are discussed. Finally, pharmaceutical monographs for ion-exchange resins are reviewed.

Elder, David P.

2005-04-01

68

Synthesis of improved polyester resins  

NASA Technical Reports Server (NTRS)

Eighteen aromatic unsaturated polyester prepolymers prepared by a modified interfacial condensation technique were investigated for their solubility in vinyl monomers and ability to provide high char yield forming unsaturated polyester resins. The best resin system contained a polyester prepolymer of phthalic, fumaric and diphenic acids reacted with 2,7-naphthalene diol and 9,9-bis(4-hydroxyphenyl)fluorene. This prepolymer is very soluble in styrene, divinyl benzene, triallyl cyanurate, diallyl isophthalate and methylvinylpyridine. It provided anaerobic char yields as high as 41 percent at 800 C. The combination of good solubility and char yield represents a significant improvement over state-of-the-art unsaturated polyester resins. The majority of the other prepolymers had only low or no solubility in vinyl monomers. Graphite composites from this prepolymer with styrene were investigated. The cause for the observed low shear strengths of the composites was not determined, however 12-week aging of the composites at 82 C showed that essentially no changes in the composites had occurred.

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

1979-01-01

69

Scintillating 99Tc Selective Ion Exchange Resins  

SciTech Connect

Scintillating technetium (99Tc) selective ion exchange resins have been developed and evaluated for equilibrium capacities and detection efficiencies. These resins can be utilized for the in-situ concentration and detection of low levels of pertechnetate anions (99TcO4-) in natural waters. Three different polystyrene type resin support materials were impregnated with varying amounts of tricaprylmethylammonium chloride (Aliquat 336) extractant, several different scintillating fluors and wavelength shifters. The prepared resins were contacted batch-wise to equilibrium over a wide range of 99TcO4- concentrations in natural water. The measured capacities were used to develop Langmuir adsorption isotherms for each resin. 99Tc detection efficiencies were determined and up to 71.4 ± 2.6% was achieved with some resins. The results demonstrate that a low level detection limit for 99TcO4- in natural waters can be realized.

Mitchell Greenhalgh; Richard D. Tillotson

2012-07-01

70

Development of tough, moisture resistant laminating resins  

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

71

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

SciTech Connect

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.

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

1990-06-01

72

Separation of nitrogen isotopes by displacement band chromatography  

SciTech Connect

A study of the separation of /sup 14/N and /sup 15/N isotopes via displacement band chromatography was conducted using sulfonated styrene-divinylbenzene resins. Starting with a feed solution of 0.5 N NH/sub 4/OH (containing 51% /sup 15/N), a band was developed that generated a concentration profile ranging from 11 to 85% /sup 15/N. The separative power and HETP (height equivalent to a theoretical plate) were found to be dependent on the resin characteristics (size, crosslinkage) and operating parameters (superficial velocity, concentration). The use of a 7/10-micrometer-size, high performance resin increased the separative power by a factor of 17 and decreased the HETP by a factor of 10, when compared to a 100/200 mesh Dowex 50W-X12 resin under similar process conditions. The HETP could further be reduced by lowering the superficial velocity and/or eluant concentration.

Park, W.K.; Michaels, E.D.

1988-10-01

73

Porous Ceramic Spheres from Ion Exchange Resin  

NASA Technical Reports Server (NTRS)

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.

Dynys, Fred

2005-01-01

74

Interferometric study of epoxy resin gelation  

SciTech Connect

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.

Hirschbuehler, K.R.

1981-01-01

75

Characterization of PMR polyimide resin and prepreg  

NASA Technical Reports Server (NTRS)

Procedures for the chemical characterization of PMR-15 resin solutions and graphite-reinforced prepregs were developed, and a chemical data base was established. In addition, a basic understanding of PMR-15 resin chemistry was gained; this was translated into effective processing procedures for the production of high quality graphite composites. During the program the PMR monomers and selected model compounds representative of postulated PMR-15 solution chemistry were acquired and characterized. Based on these data, a baseline PMR-15 resin was formulated and evaluated for processing characteristics and composite properties. Commercially available PMR-15 resins were then obtained and chemically characterized. Composite panels were fabricated and evaluated.

Lindenmeyer, P. H.; Sheppard, C. H.

1984-01-01

76

Graphite composites with advanced resin matrices  

NASA Technical Reports Server (NTRS)

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.

Kourtides, D. A.

1980-01-01

77

Novolak resin analogs for resist applications  

NASA Astrophysics Data System (ADS)

Novolak resins, used to make typical g or i-line resists, are commonly made by condensing phenolic monomers with aldehydes. In the strictest definition of novolaks the aldehyde of choice is always formaldehyde. Under the acid catalyzed conditions generally used to make novolak the resins the carbocations formed by the protonation of the aldehydic carbonyl react with the phenolic reactant(s) to form the resins with elimination of water. Other aldehydes or low molecular weight ketones have been used on occasion to make useful analog for resist applications. Competing aldol condensations may interfere with isolation of pure polymeric resins especially in the case of ketones. Unique novolak resin analogs have been made by condensing `masked' bifunctional electrophiles with phenolic reactants under acidic conditions similar to standard novolak resin techniques. These resins were used as replacements for novolak resins and showed increased image contrast and thermal resistance. They were also used as photoactive compound backbones. Low molecular weight resins made with polyhydroxy aromatic phenolic monomers were especially useful as speed enhancing additives in thick film applications.

Wanat, Stan F.; Jensen, Kathryn H.; Lu, Ping-Hung; McKenzie, Douglas S.

1998-06-01

78

Sand control with resin and explosive  

SciTech Connect

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 resin solution remaining in the wellbore after step (c) through the perforations with a displacing fluid; and injecting a chemical solution through the perforations to cause the resin to polymerize to form a consolidated permeable matrix.

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

1992-09-08

79

Resin flow analysis with fiber preform deformation in through thickness direction during Compression Resin Transfer Molding  

Microsoft Academic Search

Resin flow during Compression Resin Transfer Molding (CRTM) can be best described and analyzed in three phases. In the first phase, a gap is created by holding the upper mold platen parallel to the preform surface at a fixed distance from it. The desired amount of resin injected into the gap quickly flows primarily over the preform. The second phase

Justin Merotte; Pavel Simacek; Suresh G. Advani

2010-01-01

80

Failure load of acrylic resin denture teeth bonded to high impact acrylic resins  

Microsoft Academic Search

Statement of problem. Techniques for bonding denture teeth to an acrylic resin denture base remain empirical, with little consensus from the literature, among clinicians, or among dental laboratories. Purpose. This study evaluated the failure load of acrylic resin teeth bonded to 2 high impact acrylic resins. Methods and material. The ridge lap portion on 120 identical denture teeth were modified

Donna Barpal; Donald A. Curtis; Frederick Finzen; Jovin Perry; Stuart A. Gansky

1998-01-01

81

75 FR 67105 - Granular Polytetrafluoroethylene Resin From Italy and Japan  

Federal Register 2010, 2011, 2012, 2013

...Polytetrafluoroethylene Resin From Italy and Japan AGENCY: United States International Trade...polytetrafluoroethylene resin from Italy and Japan...polytetrafluoroethylene resin from Italy and Japan would be likely to lead to...

2010-11-01

82

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2012-07-01

83

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2011-07-01

84

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2013-07-01

85

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2010-07-01

86

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2012 CFR

...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...

2012-04-01

87

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2013 CFR

...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...

2013-04-01

88

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2011 CFR

...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...

2011-04-01

89

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

...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...

2014-04-01

90

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2013-04-01

91

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2010-04-01

92

21 CFR 872.3770 - Temporary crown and bridge resin.  

...2014-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2014-04-01

93

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2012-04-01

94

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2011-04-01

95

Sulfonated Petroleum Polymeric Resins as Plasticizers for Cement Mortars  

Microsoft Academic Search

Sulfonation of petroleum polymeric resins based on the C9 fraction with various suilfonatic agents was studied, and procedure was developed for preparing sulfonated resins. The possibility of using sulfo resins as effective plasticizers for concrete was examined.

V. P. Lesnyak; L. V. Gaponik; V. P. Mardykin; F. N. Kaputskii

2003-01-01

96

Imide modified epoxy matrix resins  

NASA Technical Reports Server (NTRS)

Results of a program designed to develop tough imide modified epoxy (IME) resins cured by bisimide amine (BIA) hardeners are presented. State of the art epoxy resin, MY720, was used. Three aromatic bisimide amines and one aromatic aliphatic BIA were evaluated. BIA's derived from 6F anhydride (3,3 prime 4,4 prime-(hexafluoro isopropyl idene) bis (phthalic anhydride) and diamines, 3,3 prime-diam nodiphenyl sulfone (3,3 prime-DDS), 4,4 prime-diamino diphenyl sulfone (4,4 prime-DDS), 1.12-dodecane diamine (1,12-DDA) were used. BIA's were abbreviated 6F-3,3 prime-DDS, 6F-4,4 prime-DDS, 6F-3,3 prime-DDS-4,4 prime DDS, and 6F-3,3 prime-DDS-1,12-DDA corresponding to 6F anhydride and diamines mentioned. Epoxy resin and BIA's (MY720/6F-3,3 prime-DDS, MY720/6F-3,3 prime-DDS-4,4 prime-DDS, MY720/6F-3,3 prime-DDS-1,12-DDA and a 50:50 mixture of a BIA and parent diamine, MY720/6F-3,3 prime-DDS/3,3 prime-DDS, MY720/6F-3,3 prime-DDS-4,4 prime-DDS/3,3 prime-DDS, MY720/6F-3,3 prime-DDS-1,12-DDA/3,3 prime-DDS were studied to determine effect of structure and composition. Effect of the addition of two commercial epoxies, glyamine 200 and glyamine 100 on the properties of several formulations was evaluated. Bisimide amine cured epoxies were designated IME's (imide modified epoxy). Physical, thermal and mechanical properties of these resins were determined. Moisture absorption in boiling water exhibited by several of the IME's was considerably lower than the state of the art epoxies (from 3.2% for the control and state of the art to 2.0 wt% moisture absorption). Char yields are increased from 20% for control and state of the art epoxies to 40% for IME resins. Relative toughness characteristics of IME resins were measured by 10 deg off axis tensile tests of Celion 6000/IME composites. Results show that IME's containing 6F-3,3 prime-DDS or 6F-3,3 prime-DDS-1,12-DDA improved the "toughness" characteristics of composites by about 35% (tensile strength), about 35% (intralaminar shear strength), and about 78% (shear strain to failure) relative to the control composite.

Scola, D. A.

1982-01-01

97

Polyimide Resins Resist Extreme Temperatures  

NASA Technical Reports Server (NTRS)

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.

2009-01-01

98

21 CFR 177.1500 - Nylon resins.  

...ibr_locations.html. (ii) The viscosity number (VN) for Nylon 6/69 and Nylon PA-6-3-T resins in a 99 percent cresol solution (5 milligrams resin per milliliter) shall be determined at 25 °C (77 °F) by method ISO...

2014-04-01

99

Ethynyl-Containing Aromatic Polyamide Resins.  

National Technical Information Service (NTIS)

In accordance with the present invention there is provided a novel aromatic polyamide resin having repeating units, each containing at least one o-ethynyl amido subunits. The resins of this invention which contain the above subunit can be thermally treate...

R. C. Evers

1985-01-01

100

Fluorinated diamond bonded in fluorocarbon resin  

SciTech Connect

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.

Taylor, Gene W. (Los Alamos, NM)

1982-01-01

101

Fluorinated diamond bonded in fluorocarbon resin  

SciTech Connect

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.

Taylor, G.W.

1982-08-10

102

Gold recovery with ion exchange used resins  

Microsoft Academic Search

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

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

2001-01-01

103

Novel process of isolating novolac resin fractions  

NASA Astrophysics Data System (ADS)

Typical phenol/formaldehyde resin syntheses generate a broad distribution of molecular weight fragments with a wide polydispersity. A process was developed to isolate novolak resin fractions of narrow polydispersity from phenol- formaldehyde condensation products in ethyl lactate without any high temperature distillation. The characterization and the performance of these fractions in i-line photoresist composition are discussed.

Rahman, M. D.; Lu, Ping-Hung; Cook, Michelle M.

1997-07-01

104

Resin/graphite fiber composites  

NASA Technical Reports Server (NTRS)

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.

Cavano, P. J.

1974-01-01

105

Release and toxicity of dental resin composite  

PubMed Central

Dental resin composite that are tooth-colored materials have been considered as possible substitutes to mercury-containing silver amalgam filling. Despite the fact that dental resin composites have improved their physico-chemical properties, the concern for its intrinsic toxicity remains high. Some components of restorative composite resins are released in the oral environment initially during polymerization reaction and later due to degradation of the material. In vitro and in vivo studies have clearly identified that these components of restorative composite resins are toxic. But there is a large gap between the results published by research laboratories and clinical reports. The objective of this manuscript was to review the literature on release phenomenon as well as in vitro and in vivo toxicity of dental resin composite. Interpretation made from the recent data was also outlined. PMID:23293458

Gupta, Saurabh K.; Saxena, Payal; Pant, Vandana A.; Pant, Aditya B.

2012-01-01

106

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

NASA Astrophysics Data System (ADS)

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.

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

2002-12-01

107

Solidification of ion exchange resin wastes  

SciTech Connect

Solidification media investigated included portland type I, portland type III and high alumina cements, a proprietary gypsum-based polymer modified cement, and a vinyl ester-styrene thermosetting plastic. Samples formulated with hydraulic cement were analyzed to investigate the effects of resin type, resin loading, waste-to-cement ratio, and water-to-cement ratio. The solidification of cation resin wastes with portland cement was characterized by excessive swelling and cracking of waste forms, both after curing and during immersion testing. Mixed bed resin waste formulations were limited by their cation component. Additives to improve the mechanical properties of portland cement-ion exchange resin waste forms were evaluated. High alumina cement formulations dislayed a resistance to deterioration of mechanical integrity during immersion testing, thus providing a significant advantage over portland cements for the solidification of resin wastes. Properties of cement-ion exchange resin waste forms were examined. An experiment was conducted to study the leachability of /sup 137/Cs, /sup 85/Sr, and /sup 60/Co from resins modified in portland type III and high alumina cements. The cumulative /sup 137/Cs fraction release was at least an order of magnitude greater than that of either /sup 85/Sr or /sup 60/Co. Release rates of /sup 137/Cs in high alumina cement were greater than those in portland III cement by a factor of two.Compressive strength and leach testing were conducted for resin wastes solidified with polymer-modified gypsum based cement. /sup 137/Cs, /sup 85/Sr, and /sup 60/Co fraction releases were about one, two and three orders of magnitude higher, respectively, than in equivalent portland type III cement formulations. As much as 28.6 wt % dry ion exchange resin was successfully solidified using vinyl ester-styrene compared with a maximum of 25 wt % in both portland and gypsum-based cement.

Not Available

1982-08-01

108

Magnetic ion-exchange resin treatment: impact of water type and resin use.  

PubMed

Three raw waters of fundamentally different natural organic matter (NOM) character were treated by magnetic resin using a bench-scale method designed to mimic how the resin is used in continuous operation. Increasing water hydrophobicity resulted in reduced dissolved organic carbon (DOC) removal with removal of 56%, 33% and 25% for waters containing 21%, 50% and 75% hydrophobic NOM, respectively. Study of consecutive resin uses showed that the NOM in the hydrophobic water had high affinity for the resin shown by DOC removal of 65% after the first use of the resin. This dropped to 25% DOC removal after 15 consecutive resin uses. For the more hydrophilic waters, NOM removal remained consistent after each resin use. The hydrophobic sample contained higher MW NOM that was capable of blocking resin sites that prevented continual adsorption of organics on to the resin. The hydrophilic NOM containing a large proportion of hydrophilic acids was consistently removed to around 60%. The water containing algogenic-derived NOM was poorly removed by magnetic resin. Subsequent coagulation showed higher removal with increasing hydrophobicity. PMID:18155745

Mergen, Max R D; Jefferson, Bruce; Parsons, Simon A; Jarvis, Peter

2008-04-01

109

Resin/graphite fiber composites  

NASA Technical Reports Server (NTRS)

Processing techniques were developed for the fabrication of both polyphenylquinoxaline and polyimide composites by the in situ polymerization of monomeric reactants directly on the graphite reinforcing fibers, rather than using previously prepared prepolymer varnishes. Void-free polyphenylquinoxaline composites were fabricated and evaluated for room and elevated flexure and shear properties. The technology of the polyimide system was advanced to the point where the material is ready for commercial exploitation. A reproducible processing cycle free of operator judgment factors was developed for fabrication of void-free composites exhibiting excellent mechanical properties and a long time isothermal life in the range of 288 C to 316 C. The effects of monomer reactant stoichiometry and process modification on resin flow were investigated. Demonstration of the utility and quality of this polyimide system was provided through the successful fabrication and evaluation of four complex high tip speed fan blades.

Cavano, P. J.

1974-01-01

110

Tc-99 Ion Exchange Resin Testing  

SciTech Connect

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.

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

2010-08-01

111

Removing Aquatic Organic Substances by Anion Exchange Resins  

Microsoft Academic Search

The focus of this study was verification of the mechanisms of removal of aquatic organic substances by anion exchange resins, influence of resin properties and clarification processes on removal, and Chromatographie behavior of organic substances in anion exchange columns. Depending on the type of resin and the nature of the organic matter, anion exchange resins removed up to 80 percent

Paul L. K. Fu; James M. Symons

1990-01-01

112

Microleakage at the resin-alloy interface of chemically retained composite resins for cast restorations.  

PubMed

New retentive mechanisms between veneering resins and casting alloys are claimed to have a chemical bond that results in a high bond strength combined with low microleakage between the veneering resin and cast restoration. This study compared the microleakage of four chemical bonding mechanisms when three veneering resins were bonded to two dental casting alloys. Resin-veneered alloy disks were immersed in red India ink and kept at 37 degrees C for 72 hours. The disks were then bench dried for 24 hours. The resin veneer was sectioned into eight sectors in an engineering milling machine and these resin sectors were removed to display the microleakage pattern. It was concluded that (1) no microleakage was found in two combinations, and (2) the highest microleakage was with Sr-Isosit-N/Panavia EX/Firmilay combinations. PMID:1712849

Strygler, H; Nicholls, J I; Townsend, J D

1991-06-01

113

EP-toxicity test of saturated GT-73 resin and resin in grout  

SciTech Connect

The results of EP-toxicity tests on mercury saturated Duolite{reg sign} GT-73 cation exchange resin clarify options for the ultimate disposal of spent resin. Samples of GT-73 saturated with mercury passed the EP-toxicity test, indicating that fully spent resin may be classifed as solid''-not hazardous''-waste and stored or disposed-of as such. Samples of GT-73 resin saturated with mercury and then incorporated into Portland Type 1 cement did not pass the EP-toxicity test and fall into the hazardous waste'' category. Samples of GT-73 resin less-than-saturated with mercury which were in corporated in Portland Type 1 cement passed the EP-toxicity test and may be classified as solid waste.'' Other commercially available materials are being investigated for incorporating fully spent GT-73 resin in a solid waste form.

Bibler, J.P.

1985-04-24

114

4META Opaque Resin — A New Resin Strongly Adhesive to Nickel-Chromium Alloy  

Microsoft Academic Search

Opaque resins lacking adhesion and mechanical retention devices are required in positioning crowns; the average bond strength in such cases is 60-70 kg\\/cm2. An adhesive opaque resin containing 4-methacryloxyethyl trimellitate anhydride was prepared for use with acrylic veneer crowns, and its bond strength and durability of adhesion with an alloy were studied. Its bonding strength between cured resin and dental

T. Tanaka; K. Nagata; M. Takeyama; M. Atsuta; N. Nakabayashi; E. Masuhara

1981-01-01

115

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

Microsoft Academic Search

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

Carper

1990-01-01

116

Hydraulic Permeability of Resorcinol-Formaldehyde Resin  

SciTech Connect

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

Taylor, Paul Allen [ORNL

2010-01-01

117

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

Microsoft Academic Search

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

Guangbo He; Bernard Riedl

2004-01-01

118

Evaluation of ultrafiltration membranes in the purification of guayule resin  

E-print Network

. Extensive research on the utilization of guayule resin is being conducted (5) resulting in a need to fractionate certain constituents of the resin to suit specific purposes. Research on the composition of the resin is still going on and about, 44 wtFs of...' the resin remains uncharacterized. The characterized portion consists of glycolipids, phosphatidic acids, flavonoids (6), flavonoid glyco- sides, solubilized lignins and polyacetylenes (7). Analyses have also indicated tliat the resin composition changes...

Jeyaseelan, Ranjit S.

2012-06-07

119

Method for regenerating magnetic polyamine-epichlorohydrin resin  

DOEpatents

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

Kochen, R.L.; Navratil, J.D.

1997-07-29

120

Method for regenerating magnetic polyamine-epichlorohydrin resin  

DOEpatents

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

Kochen, Robert L. (Boulder, CO); Navratil, James D. (Simi Valley, CA)

1997-07-29

121

Removal of Trace Contaminants from Water Using New Chelating Resins  

Microsoft Academic Search

The modification of cross?linked polyacrylamide (CPAAm) and incorporation of methyl thiourea (MeTU) or phenyl thiourea (PhTU) group were utilized in the preparation of two new chelating resins CPAAm?EDA?MeTU (resin I) and CPAAM?EDA?PhTU (resin II), [EDA=ethylenediamine]. The prepared resins were characterized by elemental analysis and IR spectroscopy. The sorption behaviors of Cd(II), Pb(II), and Zn(II) ions on the prepared resins were

Mohammed A. Sharaf; Said A. Sayed; Ahmed A. Younis; A. B. Farag; Hassan A. Arida

2007-01-01

122

Nano/microstructured ion exchange resins and their applications.  

PubMed

Ion exchange resins, due to their specific nano/microstructures and applications, have attracted great attention in the past decades. This paper reviews the recent advances and applications of nano/microstructured ion exchange resins, with an introduction to the preparation and property of different ion exchange resins. The applications of different ion exchange resins in catalysts, medicine, metallurgical regeneration, metals, and chemicals removal are summarized and discussed. The perspectives for the future developments of ion exchange resins are also proposed. PMID:24749456

Yu, Bing; Cong, Hailin; Yuan, Hua; Liu, Xuesong; Jiao, Mingming; Wang, Dong

2014-02-01

123

21 CFR 177.1580 - Polycarbonate resins.  

Code of Federal Regulations, 2011 CFR

...transporting, or holding food, in accordance with the following prescribed conditions: (a) Polycarbonate resins are polyesters produced by: (1) The condensation of 4,4?-iso-propylidenediphenol and carbonyl chloride to which may have...

2011-04-01

124

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2013 CFR

...regulations/ibr_locations.html. (ii) A minimum weight-average molecular weight of 27,000, as determined by gel permeation chromatography using polystyrene standards. (2) Extractives limitations. The polyestercarbonate resins to be...

2013-04-01

125

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 CFR

...regulations/ibr_locations.html. (ii) A minimum weight-average molecular weight of 27,000, as determined by gel permeation chromatography using polystyrene standards. (2) Extractives limitations. The polyestercarbonate resins to be...

2010-04-01

126

21 CFR 177.1585 - Polyestercarbonate resins.  

...regulations/ibr_locations.html. (ii) A minimum weight-average molecular weight of 27,000, as determined by gel permeation chromatography using polystyrene standards. (2) Extractives limitations. The polyestercarbonate resins to be...

2014-04-01

127

Silicone modified resins for graphite fiber laminates  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

128

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2010 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2010-04-01

129

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2012 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2012-04-01

130

21 CFR 177.1556 - Polyaryletherketone resins.  

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2014-04-01

131

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2013 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2013-04-01

132

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2011 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2011-04-01

133

21 CFR 177.1680 - Polyurethane resins.  

...3-Tetramethylbutyl) - phenyl]-omega- hydroxypoly(oxyethylene) (5 moles), average molecular weight 425. Trimethylol propane. (b) Optional adjuvant substances employed in the production of the polyurethane resins or added thereto to impart...

2014-04-01

134

Radiation testing of organic ion exchange resins  

SciTech Connect

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}.

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

1995-09-01

135

Cesium-specific phenolic ion exchange resin  

DOEpatents

A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio. 2 figs.

Bibler, J.P.; Wallace, R.M.

1995-08-15

136

Cesium-specific phenolic ion exchange resin  

DOEpatents

A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio.

Bibler, Jane P. (Aiken, SC); Wallace, Richard M. (Aiken, SC)

1995-01-01

137

Ion Exchange Temperature Testing with SRF Resin  

SciTech Connect

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.

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

2012-03-01

138

[Resin-bonded fixed partial dentures].  

PubMed

A resin-bonded fixed partial denture is a prosthetic construction which can replace I or several teeth in an occlusal system and which comprises a pontic element which is adhesively attached to 1 or more abutment teeth. To compensate for the limited shear strength of the adhesive layer, the Jixed partial denture is occlusally supported by the abutment(s). A direct resin-bonded fixed partial denture is made of composite, reinforced or not by a frame of flexible metal or fiber material. For an indirect resin-bonded fixed partial denture, a metal, fibre-reinforced composite or ceramic substructure is fabricated in a dental laboratory. The basic principle of a resin-bonded fixed partial denture is minimal invasiveness. However, a restoration in an abutment tooth requires a certain occlusal space which is realized by tooth preparation. Resistance preparations may be performed to improve the longevity of resin-bonded fixed partial dentures. Both financially and biologically, a resin-bonded bridge is a cost-effective prosthetic construction. The longevity is limited, but when the construction fails the negative consequences for the abutments are generally limited, which leaves open several types of other treatments. PMID:23495569

Kreulen, C M; Creugers, N H J

2013-02-01

139

Epoxy resin system for in situ rehabilitation of pipes  

SciTech Connect

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.

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

1992-04-14

140

Switch to an advanced ion exchange resin cuts boiler costs  

SciTech Connect

This article discusses how a field study demonstrated how that one refinery could save $384,000/yr by changing boiler feedwater ion exchange resin. Constant deterioration of ion exchange resin, used to demineralize boiler feedwater, prompted Star Enterprise to conduct a side-by-side evaluation of two resins. The study compared the macroporous weak base anion (WBA) resin that the refinery had used for years with a new WBA resin that features a uniform particle size. The results of this field trial, which was conducted over an 18-month period, showed that the uniform particle size resin had a higher resistance to organic fouling and produced an average of 28 percent more treated water per cycle than the old resin. Replacement and regeneration costs with the new resin resulted in a $48,000 annual savings per bed of resin.

Kratzer, W.R.; Coker, S.D.

1994-10-01

141

Magnetic ion-exchange resin treatment: Impact of water type and resin use  

Microsoft Academic Search

Three raw waters of fundamentally different natural organic matter (NOM) character were treated by magnetic resin using a bench-scale method designed to mimic how the resin is used in continuous operation. Increasing water hydrophobicity resulted in reduced dissolved organic carbon (DOC) removal with removal of 56%, 33% and 25% for waters containing 21%, 50% and 75% hydrophobic NOM, respectively. Study

Max R. D. Mergen; Bruce Jefferson; Simon A. Parsons; Peter Jarvis

2008-01-01

142

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

Microsoft Academic Search

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

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

2007-01-01

143

Effect of resin hydrophilicity and temperature on water sorption of dental adhesive resins  

Microsoft Academic Search

This study examined the effects of copolymer hydrophilicity and temperature on water sorption and solubility characteristics of five copolymer blends of increasing degree of hydrophilicity using gravimetric measurements. Six resin disks (15mm in diameter×1mm in thickness) were prepared from each copolymer blend and were stored in deionised water at 23, 37 and 55°C. Water sorption and solubility of the resin

Cynthia K. Y. Yiu; Nigel M. King; Marcela R. O. Carrilho; Salvatore Sauro; Frederick A. Rueggeberg; Carlo Prati; Ricardo M. Carvalho; David H. Pashley; Franklin R. Tay

2006-01-01

144

Emulsion Paint of Aromatic Petroleum Resin. I. Emulsification of Aromatic Petroleum Resin Solution in Water  

Microsoft Academic Search

Industrial emulsification of an aromatic petroleum resin solu tion in bodied linseed oil was investigated using an emulsion inversion process. It was found that the preferred surfactant had the best match in solubility parameter between olefinic group and resin solution A slight variation was found in optimum H LB for emulsification, depending on the chemical family of surfactants chosen, but

Yoshiyuki Iwase

1980-01-01

145

Thermal cycling effects on adhesion of resin-bovine enamel junction among different composite resins.  

PubMed

Thermal cycling is used to mimic the changes in oral cavity temperature experienced by composite resins when used clinically. The purpose of this study is to assess the thermal cycling effects of in-house produced composite resin on bonding strength. The dicalcium phosphate anhydrous filler surfaces are modified using nanocrystals and silanization (w/NP/Si). The resin is compared with commercially available composite resins Filtek Z250, Z350, and glass ionomer restorative material GIC Fuji-II LC (control). Different composite resins were filled into the dental enamel of bovine teeth. The bond force and resin-enamel junction graphical structures of the samples were determined after thermal cycling between 5 and 55°C in deionized water for 600 cycles. After thermal cycling, the w/NP/Si 30wt%, 50wt% and Filtek Z250, Z350 groups showed higher shear forces than glass ionomer GIC, and w/NP/Si 50wt% had the highest shear force. Through SEM observations, more of the fillings with w/NP/Si 30wt% and w/NP/Si 50wt% groups flowed into the enamel tubule, forming closed tubules with the composite resins. The push-out force is proportional to the resin flow depth and uniformity. The push-out tubule pore and resin shear pattern is the most uniform and consistent in the w/NP/Si 50wt% group. Accordingly, this developed composite resin maintains great mechanical properties after thermal cycling. Thus, it has the potential to be used in a clinical setting when restoring non-carious cervical lesions. PMID:25047352

Chen, Wen-Cheng; Ko, Chia-Ling; Wu, Hui-Yu; Lai, Pei-Ling; Shih, Chi-Jen

2014-10-01

146

New bismaleimide matrix resins for graphite fiber composites  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

147

Thermal rearrangement of novolak resins used in microlithography  

NASA Astrophysics Data System (ADS)

Changes in phenolic-formaldehyde resin properties are described in terms of thermal exposure. At high temperature, resin molecular weight, dissolution properties and chemical composition change depending on the presence or absence of monomers. Without monomer in the resin melt at 220 degree(s)C, resin molecular weight increases with a corresponding decrease in dissolution rate. In the presence of monomer, molecular weight generally decreases. Dissolution rate may fluctuate depending on the monomer mixture. Three,five- Xylenol and 2,3,5-trimethylphenol co-monomers induced the most extreme changes in resin properties with thermal treatment. Resin degradation-recombination processes suggest a classical Friedel-Craft rearrangement mechanism.

Hardy, Ricky; Zampini, Anthony; Monaghan, Michael J.; O'Leary, Michael J.; Cardin, William J.; Eugster, Timothy J.

1995-06-01

148

Diffusion of residual monomer in polymer resins.  

PubMed Central

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

Piver, W T

1976-01-01

149

Development of a heterogeneous laminating resin system  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

150

Improved high temperature resistant matrix resins  

NASA Technical Reports Server (NTRS)

The objective was to develop organic matrix resins suitable for service at temperatures up to 644 K (700 F) and at air pressures up to 0.4 MPa (60 psia) for time durations of a minimum of 100 hours. Matrix resins capable of withstanding these extreme oxidative environmental conditions would lead to increased use of polymer matrix composites in aircraft engines and provide significant weight and cost savings. Six linear condensation, aromatic/heterocyclic polymers containing fluorinated and/or diphenyl linkages were synthesized. The thermo-oxidative stability of the resins was determined at 644 K and compressed air pressures up to 0.4 MPa. Two formulations, both containing perfluoroisopropylidene linkages in the polymer backbone structure, exhibited potential for 644 K service to meet the program objectives. Two other formulations could not be fabricated into compression molded zero defect specimens.

Chang, G. E.; Powell, S. H.; Jones, R. J.

1983-01-01

151

[Allergic contact eczema from epoxy resin].  

PubMed

Epoxy resins are plastics that are widely used as electrical insulation, in coatings, and as adhesives and paints. They have strong sensitizing power and are one of the main causes of allergic contact eczema, both in the workplace and elsewhere. We present the case of a worker at a plastics/chemical plant, who handled aeronautical components in the process of manufacturing fuselage parts. He consulted his physician because of eczematous lesions on his fingers, hands and forearms which had developed over a two-year period and were clearly related to his work. The standard battery of skin tests was performed, along with the plastics and adhesives series and tests using the products from his workplace. Positivity was shown to epoxy resins (standard battery) and to the products from his workplace, which included different fiberglass and carbon fiber sheets impregnated with epoxy resins and epoxy adhesives. PMID:16476309

Calzado, Leticia; Ortiz-de Frutos, Francisco J; del Prado Sánchez-Caminero, María; Galera, Carmen María; Valverde, Ricardo; Vanaclocha, Francisco

2005-11-01

152

Jetted mixtures of particle suspensions and resins  

NASA Astrophysics Data System (ADS)

Drop-on-demand (DoD) ink-jetting of hard particle suspensions with volume fraction ? ˜ 0.25 has been surveyed using 1000 ultra-high speed videos as a function of particle size (d90 = 0.8—3.6 ?m), with added 2 wt. % acrylic (250 kDa) or 0.5 wt. % cellulose (370 kDa) resin, and also compared with Newtonian analogues. Jet break-off times from 80 ?m diameter nozzles were insensitive (120 ± 10 ?s) to particle size, and resin jet break-off times were not significantly altered by >30 wt. % added particles. Different particle size grades can be jetted equally well in practice, while resin content effectively controls DoD break-off times.

Hoath, S. D.; Hsiao, W.-K.; Hutchings, I. M.; Tuladhar, T. R.

2014-10-01

153

Reduction of non-enzymatic browning of orange juice and semi-concentrates by removal of reaction substrate.  

PubMed

A study was conducted to standardize the technology for the removal of amino acids (one of the browning reaction substrates) from sweet orange cv. Malta Common juice to reduce colour and quality deterioration in single strength juice and during subsequent concentration. Juice of sweet orange (Citrus sinensis) cv. Malta Common fruits was extracted by screw type juice extractor, preserved in 500 ppm SO2 and clarified by using "Pectinase CCM" enzyme (0.2% for 2 h at 50?±?2 °C). For removal of amino acids juice was passed under gravity through a glass column packed with an acidic cation exchange resin (CER), Dowex-50 W and quantity to be treated in one lot was standardized. The CER treated and untreated juices were concentrated to 15 and 30°Brix in a rotary vacuum evaporator. Results indicate that 121 ml of orange juice when passed through a glass column (5 cm internal diameter) packed with cation exchange resin (Dowex-50 W) upto a height of 8 cm, could remove about 98.4% of the amino acids with minimum losses in other juice constituents. With cation exchange resin treatment, the non-enzymatic browning and colour deterioration of orange juice semi-concentrates was reduced to about 3 folds in comparison to untreated counterparts. The retention of vitamin C and sugars was also better in semi-concentrates prepared from cation exchange resin treated juice. Thus, cation exchange resin treatment of orange juice prior to concentration and storage is highly beneficial in reduction of non-enzymatic browning, colour deterioration and retention of nutritional, sensory quality of product during preparation and storage. PMID:24966423

Sharma, Satish K; Juyal, Shashibala; Rao, V K; Yadav, V K; Dixit, A K

2014-07-01

154

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

PubMed

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

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

2012-11-01

155

Standard tests for toughened resin composites, revised edition  

NASA Technical Reports Server (NTRS)

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.

1983-01-01

156

Resin additive improves performance of high-temperature hydrocarbon lubricants  

NASA Technical Reports Server (NTRS)

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.

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

1971-01-01

157

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Polysulfide polymer-polyepoxy resins. 177.1650 Section...CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components...Surfaces § 177.1650 Polysulfide polymer-polyepoxy resins....

2011-04-01

158

Influence of resin coating materials on Porphyromonas gingivalis attachment.  

PubMed

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

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

2012-02-01

159

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2013 CFR

21 Food and Drugs 6 2013-04-01... Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... Acrylamide-acrylic acid resin....

2013-04-01

160

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2012 CFR

21 Food and Drugs 6 2012-04-01... Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... Acrylamide-acrylic acid resin....

2012-04-01

161

Benzonorbornadiene end caps for PMR resins  

NASA Technical Reports Server (NTRS)

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.

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

1992-01-01

162

Occupational dermatitis to epoxydic and phenolic resins.  

PubMed

Contact dermatitis to epoxydic and phenolic resins are the most frequent contact dermatoses due to plastics, in particular in the form of airborne dermatitis. The chemical formulas of the various components of these resins and their additives are complex and the patch tests available in the trade are insufficient and often arrive at a late stage in the progress of industry, in particular in advanced technologies like aeronautical engineering, shipbuilding or the new floor and wall coverings in buildings. This article is a review of the actions to be taken with these allergies, as well as with regards to their diagnosis, prevention and medico-legal compensation. PMID:19349256

Geraut, Christian; Tripodi, Dominique; Brunet-Courtois, Béatrice; Leray, Fabrice; Geraut, Laurent

2009-01-01

163

Use of crystalline, crosslinked synthetic resins as a storage material in latent heat stores  

SciTech Connect

The invention relates to the use of crystalline resins as storage material in latent heat accumulators. Crystalline synthetic resins replace the crystalline inorganic salt of the known latent heat reservoirs. Preferably epoxide resins, polyurethane resins and polyester resins, which contain very specific long-chain polyester molecule moieties, are used. The crystalline synthetic resins have one or more, preferably two, crystallite melt temperatures.

Kreibich, U.; Schmid, R.

1981-03-31

164

50 W thin-disk laser with variable pulse duration  

NASA Astrophysics Data System (ADS)

The laser system is based on an Yb:YAG thin-disk regenerative amplifier, which is operated in different operation modes in order to address broad spectrum of pulse durations. It is especially interesting for application development tasks, when different pulse durations can be tested to find the application optimum. For sub-picosecond pulse duration the dispersion of the regenerative amplifier output is compensated with a pair of diffraction gratings. Pulses with a full width at half maximum of 334 fs at an output power level of 30 W can be produced using a nonlinear spectrum broadening during amplification. Tuning of the distance between gratings or abandoning of the compressor allows for output pulse durations of several picoseconds with an output power of 60 W. A second seed source allows for pulse durations up to several nanoseconds. Further, the amplifier was operated in cavity-dumped or in Q-switched mode just by changing of the electrical control of the Pockels cell in the amplifier. The pulse durations range is extended, correspondingly, to 100 ns and even to microseconds.

Larionov, Mikhail; Dausinger, Friedrich

2011-02-01

165

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Polyester resin kits. 173.165 Section...Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Except for transportation by aircraft, polyester resin kits consisting of a base...

2011-10-01

166

Tensile Properties of Resin-infiltrated Demineralized Human Dentin  

Microsoft Academic Search

The ability of adhesive resins to restore the physical properties of demineralized dentin has not been well-documented. The unfilled resins that are used for adhesion have relatively low moduli of elasticity and limited ability to increase dentin stiffness, although they may increase the ultimate tensile strength of dentin. This study tested the hypothesis that resin infiltration of demineralized dentin can

H. Sano; T. Takatsu; B. Ciucchi; C. M. Russell; D. H. Pashley

1995-01-01

167

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2010-07-01

168

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2011-07-01

169

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2013-07-01

170

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2012-07-01

171

Creep behavior of epoxy resin during irradiation at cryogenic temperature  

Microsoft Academic Search

Creep tests of an epoxy resin during bending and irradiation have been carried out to investigate the synergistic effects of radiation and stress on mechanical properties of the resin. Simultaneous application of stress and irradiation on the epoxy resin enhanced creep rates in comparison with the application of stress on an irradiated sample. In order to clarify the mechanism of

Tetsuya Nishiura; Shigehiro Nishijima; Toichi Okada

1999-01-01

172

Bismaleimide resins for flame resistant honeycomb sandwich panels  

NASA Technical Reports Server (NTRS)

A 60 kg batch of Resin M751 was produced in pilot plant scale. The resin was delivered to the prepreg company as an NMP solution. 100 kg of glass-fabric prepregs were fabricated. Prepreg characteristics and curing cycles for laminate fabrication were provided. A new batch of Resin M756 (Code M756 - 2) was synthesized.

1978-01-01

173

Composites from Natural Fibers and Soy Oil Resins  

Microsoft Academic Search

The goal of this project is to develop new composites using fibers and resins from renewable resources. The ACRES (Affordable Composites from Renewable Sources) group at the University of Delaware has developed new chemistries to synthesize rigid polymers from plant oils. The resins produced contain at least 50% plant triglycerides and have mechanical properties comparable to commercially available synthetic resins

George I. Williams; Richard P. Wool

2000-01-01

174

Reusable chelating resins concentrate metal ions from highly dilute solutions  

NASA Technical Reports Server (NTRS)

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.

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

1966-01-01

175

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2013-04-01

176

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

...2014-04-01 2014-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2014-04-01

177

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2011-04-01

178

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2012-04-01

179

Occupational asthma due to unheated polyvinylchloride resin dust.  

PubMed

Polyvinylchloride (PVC) resins are widely used in industry. Asthma due to the thermal degradation products of PVC are well documented. In this first case of occupational asthma due to unheated PVC resin dust the patient was exposed to PVC resin dust during the mixing of chemicals used for making plastic seals for bottle caps. PMID:2590649

Lee, H S; Yap, J; Wang, Y T; Lee, C S; Tan, K T; Poh, S C

1989-11-01

180

Simulation of the C5 Aliphatic Petroleum Resins Production Process  

Microsoft Academic Search

Petroleum resins are used widely in many industries. They are solvable in most of aromatic and aliphatic solvents. There are different grades of petroleum resins from dark and viscose liquids to bright and hard ones. They are used mostly in the adherent industry as binder. In this article the production process of aliphatic petroleum resin is simulated based on the

B. Berahman; B. Dabir; S. Sadeghpour

2010-01-01

181

PETROLEUM RESINS: SEPARATION, CHARACTER, AND ROLE IN PETROLEUM  

Microsoft Academic Search

In petroleum science, the term resin generally implies material that has been eluted from various solid adsorbents, whereas the term maltenes (or petrolenes) indicates a mixture of the resins and oils obtained as filtrates from the asphaltene precipitation. Thus, after the asphaltenes are precipitated, adsorbents are added to the n-pentane solutions of the resins and oils, by which process the

Simon I. Andersen; James G. Speight

2001-01-01

182

Resin Powder Slurry Process for Composite Fabrication  

NASA Technical Reports Server (NTRS)

Potentially useful process for fabrication of fiber-reinforced resinmatrix composites is powder slurry technique. Applicability of technique demonstrated using powdered resin made from thermoplastic polyimide LaRC/ TPI (thermoplastic polyimide). Use of process circumvents need for such high-cost organic solvents as N-methylpyrrolidinone and diglyme (diglycol methyl ether). Two basic slurries for LaRC/TPI powder investigated.

Mike, R. A.

1986-01-01

183

Resin Vacuum Casting System for LED Screen  

Microsoft Academic Search

This paper mainly describes the resin vacuum casting system for LED screen which uses thin film degassing technology and meter mix technology. Thin film degassing technology is currently the most effective method. In this paper, we describe in detail its working model. And meter mix dispensing technology integrates metering pump and mixing pump. It mixes materials according to the demand.

Hong Robin; Wang Hongmei; Hu Ming

2010-01-01

184

Ternary Resin-Bound Dynamic Combinatorial Chemistry  

PubMed Central

The ability to carry out simultaneous orthogonal exchange chemistries has opened new opportunities for increasing the numerical and structural diversity accessible to Dynamic Combinatorial Chemistry. We present proof-of-concept experiments demonstrating this concept is transferrable to resin-bound DCC, facilitating the generation and analysis of libraries with greater structural diversity. PMID:22240966

Gromova, Anna V.; Ciszewski, Joseph M.; Miller, Benjamin L.

2013-01-01

185

Pharmaceutical Applications of Ion-Exchange Resins  

ERIC Educational Resources Information Center

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…

Elder, David

2005-01-01

186

Process for manufacturing a petroleum resin  

Microsoft Academic Search

The present invention relates to a process for manufacturing a petroleum resin wherein a fraction (Component a) containing an aromatic hydrocarbon obtained by cracking of petroleum and a thermally polymerized oil (Component b) obtained by previously thermal-polymerizing the component a are mixed and then the mixture of the components a and B is subjected to polymerization by employing a Friedel-Crafts

T. Iwashita; M. Nagano; K. Tanaka

1981-01-01

187

Resin transfer molding speeds composite making  

NASA Astrophysics Data System (ADS)

Fabrication resin transfer molding (RTM) composite parts for different industrial applications is discussed. These applications include composite aerospace parts, sports car components, and high performance sporting equipment. It is pointed out that RTM parts are lighter than metals and can be formulated to have superior durability. But like all composite parts, they are expensive and are made in limited runs.

Valenti, Michael

1992-11-01

188

Effect of posterior resin composite placement technique on the resin-dentin interface formed in vivo  

Microsoft Academic Search

Objective: The aim of this study was to evaluate the morphology of the resin-dentin interface formed in vivo with two posterior resin composite placement techniques (incremental and bulk). Method and materi- als: After approval from the patients, 12 Class II cavities with margins in enamel (2.5 2.5 4.5 mm) were prepared in caries-free premolars scheduled to be extracted for orthodontic

Guilherme Carpena Lopes; Luiz Narciso Baratieri; Sylvio Monteiro; Luiz Clóvis Cardoso Vieira

189

Resin film infusion mold tooling and molding method  

NASA Technical Reports Server (NTRS)

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.

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

1999-01-01

190

NITRATE CONVERSION OF HB-LINE REILLEXTM HPQ RESIN  

SciTech Connect

Reillex{trademark} HPQ ion exchange resin is used by HB Line to remove plutonium from aqueous streams. Reillex{trademark} HPQ resin currently available from Vertellus Specialties LLC is a chloride ionic form, which can cause stress corrosion cracking in stainless steels. Therefore, HB Line Engineering requested that Savannah River National Laboratory (SRNL) convert resin from chloride form to nitrate form in the Engineering Development Laboratory (EDL). To perform this task, SRNL treated two batches of resin in 2012. The first batch of resin from Reilly Industries Batch 80302MA was initially treated at SRNL in 2001 to remove chloride. This batch of resin, nominally 30 liters, has been stored wet in carboys since that time until being retreated in 2012. The second batch of resin from Batch 23408 consisted of 50 kg of new resin purchased from Vertellus Specialties in 2012. Both batches were treated in a column designed to convert resin using downflow of 1.0 M sodium nitrate solution through the resin bed followed by rinsing with deionized water. Both batches were analyzed for chloride concentration, before and after treatment, using Neutron Activation Analysis (NAA). The resin specification [Werling, 2003] states the total chlorine and chloride concentration shall be less than 250 ppm. The resin condition for measuring this concentration is not specified; however, in service the resin would always be fully wet. Measurements in SRNL showed that changing from oven dry resin to fully wet resin, with liquid in the particle interstices but no supernatant, increases the total weight by a factor of at least three. Therefore, concentration of chlorine or chloride expressed as parts per million (ppm) decreases by a factor of three. Therefore, SRNL recommends measuring chlorine concentration on an oven dry basis, then dividing by three to estimate chloride concentration in the fully wet condition. Chloride concentration in the first batch (No.80302MA) was nearly the same before the current treatment (759 ppm dry) and after treatment (745 ppm dry or {approx}248 ppm wet). Treatment of the second batch of resin (No.23408) was very successful. Chloride concentration decreased from 120,000 ppm dry to an average of 44 ppm dry or {approx}15ppm wet, which easily passes the 250 ppm wet criterion. Per guidance from HB Line Engineering, SRNL blended Batch 80302 resin with Batch P9059 resin which had been treated previously by ResinTech to remove chloride. The chloride concentrations for the two drums of Batch P9059 were 248 ppm dry ({approx}83 ppm wet) {+-}22.8% and 583 ppm dry ({approx}194 ppm wet) {+-} 11.8%. The blended resin was packaged in five gallon buckets.

Steimke, J.; Williams, M.; Steeper, T.; Leishear, R.

2012-05-29

191

Removal of phenol from saline water by polyamine chelating resin.  

PubMed

Removal of phenol from saline water was carried out with chelating resin. A polyamine chelating resin, Diaion CR-20, removed phenol compounds selectively from industrial wastewater containing 2% salt. From saline water containing 20 mg/L phenol, 70% of the phenol was removed. After treatment, phenol was eluted from the resin by aqueous NaOH, and the resin could also be regenerated by heating in air. Diaion CR-20 adsorbed phenol even in the presence of FeCl3, indicating that treatment with this resin of wastewater containing metal can remove phenol and metal cations in a single step. PMID:24185065

Yamada, Arisa; Matsui, Akihiro; Tsuji, Hideyuki

2013-01-01

192

Method for detecting resin leakage in LWR coolant  

SciTech Connect

Resin leakage from condensate polishing units can result in steam generator corrosion. This report describes the development of a resin leakage detection method based in analyzing the organic breakdown products released from resin on heating. The breakdown products are analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. Some of the organic products formed have been identified. A design for a resin monitoring unit, suitable for incorporation into the IONTRAC system, is presented. Theoretically, detection of ppB levels of resin by processing about one liter of water, is possible.

Girard, J.E.

1988-05-01

193

Programmed gelation of polymers using melamine resins  

SciTech Connect

This patent describes a process for enhancing the amount of oil recovered from a subterranean oil-bearing formation having relatively high permeability zones and relatively low permeability zones penetrated by at least one injection well and at least one production well by selectively plugging at least a portion of the relatively high permeability zones with a profile control gel. It comprises: determining a quantity of a gel-forming mixture required for the selective plugging of at least a portion of the relatively high permeability zones within the formation and the period of time within which full gelation of the mixture is to be completed; preparing a gel-forming mixture comprising a polymer which is crosslinkable by reaction with an amino resin, a rapid amino resin crosslinking agent and a delayed amino resin crosslinking agent, the gel-forming mixture capable of complete gelation within the period of time determined; partially gelling the mixture to impart selectivity to the mixture by reacting the polymer with the rapid amino resin crosslinking agent which is effective to complete the partial gelation by crosslinking the polymer to form a viscous liquid; injecting the viscous liquid into the relatively high permeability zones within the formation; fully gelling the viscous liquid by reacting the polymer with the delayed amino resin crosslinking agent which is effective to complete the full gelation by crosslinking the polymer within the period of time determined; injecting a flooding fluid into the relatively low permeability zones of the formation via the injection well; and recovering fluids including oil from the formation via the production well.

Shu, P.

1990-10-23

194

Electrically conductive resinous bond and method of manufacture  

DOEpatents

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.

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

195

Technique for removing resin from a molded object  

NASA Technical Reports Server (NTRS)

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.

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

1983-01-01

196

Electrically conductive resinous bond and method of manufacture  

DOEpatents

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.

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

1985-01-01

197

Study on the resin temperature developments during UV imprinting process.  

PubMed

During the imprinting process, the temperature of the UV resin increases as the phase of the resin changes from fluid into solid. During UV curing, some amount of heat is released from inside the resin and transferred into contacting materials. The heat flow is measured with photo-DSC, and other related thermal and mechanical properties of the resin. With the measured material properties, the temperature developments both inside of the resin layer and along the interfaces of the contacting materials are computed. During the UV exposure period, the thermal deformation of the mold, which directly influences the pattern distortion are investigated. Under this condition, the developments of strain and temperature inside the mold structure including the UV resin of 3-D shape are computed with the transient time scale during UV curing according to the thickness of resin layer. These computational results are expected to provide useful information for better designs of the imprinting mold and the process condition. PMID:22629908

Jeon, Jongduk; Jang, Siyoul

2012-02-01

198

Plasma treatment increased shear bond strength between heat cured acrylic resin and self-curing acrylic resin.  

PubMed

Self-curing acrylic resin is generally used for the repair of a fractured denture base. However, re-fracture of the repaired denture base resin often occurs because of poor bonding strength between the base resin and self-curing repair resin. The effect of plasma treatment on the shear bond strength between heat cured acrylic resin and the self-cured acrylic was examined. It was revealed that plasma irradiation is effective in increasing the shear bond strength. Plasma irradiation does not cause environmental pollution, as it does not require chemicals. It is a useful method to increase adhesive strength between heat cured acrylic resin and self-curing acrylic resin. PMID:14641672

Nishigawa, G; Maruo, Y; Oka, M; Oki, K; Minagi, S; Okamoto, M

2003-11-01

199

Ethynylated aromatics as high temperature matrix resins  

NASA Technical Reports Server (NTRS)

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.

Hurwitz, Frances I.

1986-01-01

200

Process for manufacturing a petroleum resin  

SciTech Connect

The present invention relates to a process for manufacturing a petroleum resin wherein a fraction (Component a) containing an aromatic hydrocarbon obtained by cracking of petroleum and a thermally polymerized oil (Component b) obtained by previously thermal-polymerizing the component a are mixed and then the mixture of the components a and B is subjected to polymerization by employing a Friedel-Crafts catalyst. It is also directed to propose a petroleum resin of a superior quality having a softening point optionally in a range of 30-120/sup 0/C and various bromine value in such a manner that a mixing ratio of the components a and B is properly adjusted.

Iwashita, T.; Nagano, M.; Tanaka, K.

1981-08-11

201

Flammability of Epoxy Resins Containing Phosphorus  

NASA Technical Reports Server (NTRS)

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.

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

2005-01-01

202

Anion-exchange resin-based desulfurization process. Final report  

SciTech Connect

The following investigations were performed: (1) batch mode screening of eleven(11) commercially available resins and selection of three candidate resins for further evaluation in a fixed-bed setup. (2) Process variables study using three candidate resins in the fixed-bed setup and selection of the ``best`` resin for process economics development. (3) Exhaustion efficiency and solution concentration were found to be inversely related necessitating a trade-off between the resin cost versus the cost of evaporation/concentration of ensuing effluents. (4) Higher concentration of the HCO{sub 3}{sup {minus}} form of active sites over less active CO{sub 3}{sup 2{minus}} form of sites in the resin was believed to be the main reason for the observed increase in the equilibrium capacity of the resin at an elevated static CO{sub 2}-pressure. This Increase in capacity was found to level off around 80--120 psig range. The increase in CO{sub 2}-pressure, however, did not appear to affect the overall ion-exchange kinetics. (5) In the fixed-bed mode, the solution concentration was found to affect the equilibrium capacity of candidate resins. Their relationship was well satisfied by the Langmuir type non-linear equilibrium isotherm. Alternatively, the effect of solution concentration on overall ion-exchange kinetics varied from resin to resin. (6) Product inhibition effect on the resin was observed as an initial increase followed by a significant decrease in the resin`s equilibrium capacity for SO{sub 4}{sup 2{minus}} as the HCO{sub 3}{sup {minus}}/SO{sub 4}{sup 2{minus}} molar ratio in the solution was increased from 0 to 1.0. This ratio, however, did not affect the overall ion-exchange kinetics.

Sheth, A C; Dharmapurikar, R; Strevel, S D

1994-01-01

203

Potential contribution of exposed resin to ecosystem emissions of monoterpenes  

NASA Astrophysics Data System (ADS)

Conifers, especially pines, produce and store under pressure monoterpene-laden resin in canals located throughout the plant. When the plants are damaged and resin canals punctured, the resin is exuded and the monoterpenes are released into the atmosphere, a process that has been shown to influence ecosystem-level monoterpene emissions. Less attention has been paid to the small amounts of resin that are exuded from branches, expanding needles, developing pollen cones, and terminal buds in the absence of any damage. The goal of this study was to provide the first estimate of the potential of this naturally-exposed resin to influence emissions of monoterpenes from ponderosa pine (Pinus ponderosa) ecosystems. When resin is first exuded as small spherical beads from undamaged tissues it emits monoterpenes to the atmosphere at a rate that is four orders of magnitude greater than needle tissue with an equivalent exposed surface area and the emissions from exuded beads decline exponentially as the resin dries. We made measurements of resin beads on the branches of ponderosa pine trees in the middle of the growing season and found, on average, 0.15 cm2 of exposed resin bead surface area and 1250 cm2 of total needle surface area per branch tip. If the resin emerged over the course of 10 days, resin emissions would make up 10% of the ecosystem emissions each day. Since we only accounted for exposed resin at a single point in time, this is probably an underestimate of how much total resin is exuded from undamaged pine tissues over the course of a growing season. Our observations, however, reveal the importance of this previously unrecognized source of monoterpenes emitted from pine forests and its potential to influence regional atmospheric chemistry dynamics.

Eller, Allyson S. D.; Harley, Peter; Monson, Russell K.

2013-10-01

204

Candida albicans adhesion to composite resin materials  

Microsoft Academic Search

The adhesion of Candida albicans to dental restorative materials in the human oral cavity may promote the occurrence of oral candidosis. This study aimed\\u000a to compare the susceptibility of 14 commonly used composite resin materials (two compomers, one ormocer, one novel silorane,\\u000a and ten conventional hybrid composites) to adhere Candida albicans. Differences in the amount of adhering fungi should be

Ralf Bürgers; Wulf Schneider-Brachert; Martin Rosentritt; Gerhard Handel; Sebastian Hahnel

2009-01-01

205

Ion Exchange Resins Transforming Drug Delivery Systems.  

PubMed

Ion-exchange resins are light, porous, three-dimensional high molecular weight cross -linked matrix of hydrocarbon chains carrying positively or negatively charged sites that can attract an ion of opposite charge from the surrounding medium. There is stoichiometric exchange of mobile ions between the solid and the solution called as Ion-exchange which does not lead to any radical change in the properties and structure of the solid. Depending upon the type of Ionexchanged it can be either Cation-exchange or Anion-exchange. They are prepared in the form of granules, beads or sheets. As drug delivery systems they have received considerable attention after the 1950s due to their inertness, freedom from side effects, high drug loading capacity, ease of sterilization and the fact that their structure can be easily altered to achieve the desired drug release characteristics. Their use is revolutionizing all traditional delivery systems namely- oral, nasal, ophthalmic and parenteral. Ion- exchange resins have been used for the development of novel drug delivery systems (NDDSs), to modify the characteristics of the dosage form and various other biomedical applications. The present article deals with the varied applications of ion-exchange resins for taste making, as resinates (simple and microencapsulated or coated), Pennkinetic systems, in selective recovery of pharmaceuticals, in pH and ionic strength responsive systems, in gastro-retentive systems, in hollow fiber systems, as sigmoidal release systems, as site specific delivery systems and as inotophoretically assisted transdermal drug delivery systems. They also have an immense importance when used as disintegrants/ superdisintegrants in formulation of orodispersible tablets, powder processing aids and in the dissolution and stabilization of drugs. PMID:20497105

Gupta, Shweta; Benien, Parul; Sahoo, P K

2010-05-24

206

Ion Exchange Resins Transforming Drug Delivery Systems.  

PubMed

Ion-exchange resins are light, porous, three-dimensional high molecular weight cross -linked matrix of hydrocarbon chains carrying positively or negatively charged sites that can attract an ion of opposite charge from the surrounding medium. There is stoichiometric exchange of mobile ions between the solid and the solution called as Ion-exchange which does not lead to any radical change in the properties and structure of the solid. Depending upon the type of Ion-exchanged it can be either Cation-exchange or Anion-exchange. They are prepared in the form of granules, beads or sheets. As drug delivery systems they have received considerable attention after the 1950s due to their inertness, freedom from side effects, high drug loading capacity, ease of sterilization and the fact that their structure can be easily altered to achieve the desired drug release characteristics. Their use is revolutionizing all traditional delivery systems namely- oral, nasal, ophthalmic and parenteral. Ion- exchange resins have been used for the development of novel drug delivery systems (NDDSs), to modify the characteristics of the dosage form and various other biomedical applications. The present article deals with the varied applications of ion-exchange resins for taste making, as resinates (simple and microencapsulated or coated), Pennkinetic systems, in selective recovery of pharmaceuticals, in pH and ionic strength responsive systems, in gastro-retentive systems, in hollow fiber systems, as sigmoidal release systems, as site specific delivery systems and as inotophoretically assisted transdermal drug delivery systems. They also have an immense importance when used as disintegrants / superdisintegrants in formulation of orodispersible tablets, powder processing aids and in the dissolution and stabilization of drugs. PMID:20158479

Gupta, Shweta; Parul; Sahoo, P K

2010-02-17

207

Fire- and Heat-Resistant Laminating Resins  

NASA Technical Reports Server (NTRS)

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.

Kourtides, Demetrius A.; Mikroyannidis, John A.

1987-01-01

208

Light color, low softening point hydrocarbon resins  

Microsoft Academic Search

This patent describes a hydrocarbon resin having a softening point of from 0° C to about 40° C, a Gardner color of about 7 or less, a number average molecular weight (Mn) of from about 100 to about 600, and a M{sub {ital w}}\\/M{sub {ital n}} ratio of from about 1.1 to about 2.7, prepared by Friedel Crafts polymerization of

M. L. Evans; S. G. Hentges

1990-01-01

209

Glutathione Resins I. List of Components  

E-print Network

-1) Purchase of the GST Purification Kit provides sufficient reagents for performing five batch/gravity flow Clontech · www.clontech.com · 800-662-2566 #12;GlutathioneResinProtocol · Polypropylene tubes · Centrifuge (pre-chilled to 4ºC) · TALONTM 2-ml Disposable Gravity Columns (#8903-1) · Deionized H2O · Ice · Column

Lebendiker, Mario

210

Ceramic whisker reinforcement of dental resin composites.  

PubMed

Resin composites currently available are not suitable for use as large stress-bearing posterior restorations involving cusps due to their tendencies toward excessive fracture and wear. The glass fillers in composites provide only limited reinforcement because of the brittleness and low strength of glass. The aim of the present study was to reinforce dental resins with ceramic single-crystalline whiskers of elongated shapes that possess extremely high strength. A novel method was developed that consisted of fusing silicate glass particles onto the surfaces of individual whiskers for a two-fold benefit: (1) to facilitate silanization regardless of whisker composition; and (2) to enhance whisker retention in the matrix by providing rougher whisker surfaces. Silicon nitride whiskers, with an average diameter of 0.4 microm and length of 5 microm, were coated by the fusion of silica particles 0.04 microm in size to the whisker surface at temperatures ranging from 650 degrees C to 1000 degrees C. The coated whiskers were silanized and manually blended with resins by spatulation. Flexural, fracture toughness, and indentation tests were carried out for evaluation of the properties of the whisker-reinforced composites in comparison with conventional composites. A two-fold increase in strength and toughness was achieved in the whisker-reinforced composite, together with a substantially enhanced resistance to contact damage and microcracking. The highest flexural strength (195+/-8 MPa) and fracture toughness (2.1+/-0.3 MPa x m(1/2)) occurred in a composite reinforced with a whisker-silica mixture at whisker:silica mass ratio of 2:1 fused at 800 degrees C. To conclude, the strength, toughness, and contact damage resistance of dental resin composites can be substantially improved by reinforcement with fillers of ceramic whiskers fused with silica glass particles. PMID:10029470

Xu, H H; Martin, T A; Antonucci, J M; Eichmiller, F C

1999-02-01

211

Metallic-resin compounds fuel processing process  

Microsoft Academic Search

In a demonstration plant for the recycling of post-use electric home appliances, the authors developed a metal-resin compounds fuel processing system for generated plastics and shredder dusts from this recycling plant. In this system, waste plastics and other shredder dust is thermally cracked in an oxygen-free rotary carbonization reactor with a maximum rate of 250 kg\\/h. Most of the plastic

H. Hoshina; T. Hayanose

1999-01-01

212

Thermochemical study of behavior of petroleum resins  

Microsoft Academic Search

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

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

1988-01-01

213

Morphological characterization of furfuraldehyde resins adsorbents  

SciTech Connect

Sugar cane is one of the most traditional plantation cultivated crops in large areas in Brazil. The State University of the North of Rio de Janeiro, UENF, is currently engaged in a program aimed to exploit the potentialities of sugar cane industry as a self sustained non-polluting enterprise. One of the projects being carried out at the UENF is the transformation of sugar cane bagasse in precursor materials for the industry of furan derivatives such as the furfuraldehyde resins obtained by acid catalysis. The possibility of employing acid catalyzed furfuraldehyde resins as selective adsorbents has arisen during a comprehensive study of physical-chemical adsorption properties of these materials. The morphology of these resins depend on the synthesis method. Scanning Electron Microscopic studies of these materials which were synthesized, in bulk (FH-M) and solution (FH-D), showed differences in surface density and particle size. Using mercury porosimeter techniques and BET adsorption methods, it was found different pore size distributions and a decrement in surface area when solvent was employed in the synthesis process. By thermogravimetric analysis it was found similar weight losses (6%) of water adsorption and a small differences in thermal stabilities.

Sanchez, R.; Monteiro, S.N. [State Univ. of the North of Rio de Janeiro (Brazil); D`Almeida, J.R. [Rio de Janeiro-Catholic Univ. (Brazil)

1996-12-31

214

Surface integrity of provisional resin materials  

NASA Astrophysics Data System (ADS)

Provisional resin materials are widely used in prosthetic dentistry and play an important role in the success of restorative treatment. Therefore, these materials must meet the requirements of preserving surface integrity during the treatment process. This study was done to evaluate surface roughness and microhardness of two provisional resin materials after 37 °C water storage. Two rectangular samples 21 mm × 11 mm × 3 mm, one bis-acrylic (bis-acrylic-Protemp II) and one polyethyl methacrylate (Trim®-PEMA) were fabricated as examples of provisional materials (n = 5 per material). The specimens were stored in 37 °C deionized distilled water for 24 h, 1, 2 and 3 weeks. The control specimens were not stored in water. The surface roughness of the tested materials (n = 10) was measured using a profilometer. Microhardness tests were conducted using a Vickers microscope mounted indenter system (n = 10). At 24 h, the surface roughness was recorded with bis-acrylic-Protemp II as higher than methacrylate materials. No significant differences of microhardness between Trim®-PEMA and bis-acrylic-Protemp II were recognized at 1, 2 and 3 weeks. The microhardness values increased with the increase of surface roughness and vice versa in both Trim®-PEMA and bis-acrylic-Protemp II. Both surface roughness and microhardness are affected by water storage. Bis-acrylic-Protemp II revealed better results in hardness than methacrylate resins, whereas Trim®-PEMA has a better surface roughness.

Abouelatta, O. B.; El-Bediwi, A.; Sakrana, A.; Jiang, X. Q.; Blunt, L.

2006-03-01

215

Transparent resins for 157-nm lithography  

NASA Astrophysics Data System (ADS)

The development of sufficiently transparent resin systems is one of the key elements required for a successful and timely introduction for 157 nm lithography. This paper reports on the Simple Transmission Understanding and Prediction by Incremental Dilution (STUPID) model, a quick back-of-the-envelope increment scheme to estimate the absorption of polymers at 157 nm. A number of promising candidate resins based on norbornenes are discussed, and results with a first 157 nm resin system developed at the University of Austin are presented. The new system is based on copolymers of norbornene-5-methylenehexafluoroisopropanol (NMHFA) and t-butyl norbornene carboxylate (BNC), formulated with an acetal additive obtained by copolymerization of t-butyl norbornene-5-trifluoromethyl-5-carboxylate (BNTC) with carbon monoxide. Lithographic performance of this system extends to 110 nm dense features using standard illumination and a binary mask, or 80 nm semi-dense and 60 nm isolated features with a strong phase shift mask. The dry etch resistance of this resist is found to be slightly lower than APEX-E DUV resist for polysilicon but superior to it for oxide etches.

Dammel, Ralph R.; Sakamuri, Raj; Romano, Andrew R.; Vicari, Richard; Hacker, Cheryl; Conley, Will; Miller, Daniel A.

2001-08-01

216

Chemoviscosity modeling for thermosetting resins - I  

NASA Technical Reports Server (NTRS)

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.

Hou, T. H.

1984-01-01

217

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)

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.

Alston, William B.

1988-01-01

218

CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN  

SciTech Connect

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.

Nash, C.; Duignan, M.

2010-02-23

219

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

PubMed

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

Chang, Hoon-Sang; Hong, Sung-Ok

2014-01-01

220

Machine for applying a two component resin to a roadway surface  

DOEpatents

A portable machine for spraying two component resins onto a roadway, the machine having a pneumatic control system, including apparatus 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.

Huszagh, Donald W. (Bayport, NY)

1985-01-01

221

Machine for applying a two component resin to a roadway surface  

DOEpatents

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.

Huszagh, D.W.

1984-01-01

222

Machine for applying a two component resin to a roadway surface  

SciTech Connect

A portable machine for spraying two component resins onto a roadway, the machine having a pneumatic control system, including apparatus 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.

Huszagh, D. W.

1985-07-16

223

Bismaleimide resins for flame resistant honeycomb sandwich panels  

NASA Technical Reports Server (NTRS)

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.

Stenzenberger, H. D.

1978-01-01

224

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

DOEpatents

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.

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

2011-03-29

225

Resin impregnation during the manufacturing of composite materials  

SciTech Connect

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.

Coulter, J.P.

1988-01-01

226

Improved well stimulation with resin-coated proppants  

SciTech Connect

Resin-coated proppants improve well stimulation results by preventing flowback, or fracture evacuation, near the wellbore, a phenomenon that effectively ''decouples'' the wellbore and the productive formation. In addition, the deformable coating protects the resin-coated proppants from crushing and helps resist embedment in softer formations. The tough coating is chemically inert in crude oils, brines, and most acids. The resin-coated materials work best under actual downhole conditions since the closure stress and temperature help lock the materials in the fracture for the life of the well. This paper reviews case histories from four wells in which resin-coated proppants were used. In addition, simple lab tests of the resin-coated proppants in an API crush cell confirm their excellent properties and potential. Together, these results show the need for resin-coated proppants in many types of wells. In many ways they act as ''ideal'' proppants that can be economically justified over uncoated proppants.

Sinclair, A.R.; Graham, J.W.; Sinclair, C.P.

1983-02-01

227

Versatile composite resins simplifying the practice of restorative dentistry.  

PubMed

After decades of technical development and refinement, composite resins continue to simplify the practice of restorative dentistry, offering clinicians versatility, predictability, and enhanced physical properties. With a wide range of products available today, composite resins are a reliable, conservative, multi-functional restorative material option. As manufacturers strive to improve such properties as compression strength, flexural strength, elastic modulus, coefficient of thermal expansion, water sorption, and wear resistance, several classification systems of composite resins have been developed. PMID:24571527

Margeas, Robert

2014-01-01

228

High performance mixed bisimide resins and composites based thereon  

NASA Technical Reports Server (NTRS)

Mixtures of bismaleimide/biscitraconirnide resins produces materials which have better handling, processing or mechanical and thermal properties, particularly in graphite composites, than materials made with the individual resins. The mechanical strength of cured graphite composites prepared from a 1:1 copolymer of such bisimide resins is excellent at both ambient and elevated temperatures. The copolymer mixture provides improved composites which are lighter than metals and replace metals in many aerospace applications.

Parker, J. A.; ations.

1986-01-01

229

Thermal behaviour of hydroxymethyl compounds as models for adhesive resins  

Microsoft Academic Search

Urea–formaldehyde (UF) and phenol–formaldehyde (PF) resins are the most widely used wood adhesives. The first stage in resin\\u000a manufacturing is the formation of methylol derivatives which polycondensation leads to building the tridimensional network.\\u000a Understanding the behaviour of methylol compounds in curing provides useful information for developing appropriate resin structures.\\u000a Thermal behaviour of N,N?-dihydroxymethylurea, 2- and 4-hydroxymethylphenols, urea and phenol as

K. Siimer; P. Christjanson; T. Kaljuvee; T. Pehk; I. Saks

2009-01-01

230

Characterization of petroleum resins by nuclear magnetic resonance spectrometry  

SciTech Connect

In this paper an approach to resin structure determination using /sup 1/H and /sup 13/C NMR spectrometries is presented and briefly discussed. The analyzed resin samples are prepared by catalytic and thermic polymerization of the liquid byproducts, obtained by pyrolysis of primary gasoline. The result point out the differences in resin structures depending on crude oil types as well as on the applied polymerization conditions in connection with their physical properties.

Muhl, J.; Srica, V.; Jarm, V.; Kovac-Filipovic, M.

1987-07-01

231

The Sorption Capacity of Boron on Anionic-Exchange Resin  

Microsoft Academic Search

Boron sorption capacities on anionic-exchange resins vary with temperature, concentration, and resin crosslinkage. A semiempirical correlation, developed from boron solution chemistry, is presented to account for these variations. The relationship, based on boron chemistry and changes in Gibb's energy, can be stated approximately as Q = a1CBz exp[-(a4T + a5T + a6z )]. Correlation parameters, which vary with resin type,

JIDONG LOU; GARY L. FOUTCH; JUNG WON NA

1999-01-01

232

Natural fiber composites with plant oil-based resin  

Microsoft Academic Search

Vacuum-assisted resin transfer molding or resin vacuum infusion process was used to make composite panels out of plant oil-based resin [acrylated epoxidized soybean oil (AESO)] and natural fiber mats made of flax, cellulose, pulp and hemp. The composites formed by room temperature cure with natural fiber reinforcement of about 10–50 wt% increased the flexural modulus to a range between 1.5

A O'Donnell; M. A Dweib; R. P Wool

2004-01-01

233

Chromium Ions Improve Moisure Resistance of Epoxy Resins  

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

234

Quantifying the Strength of a Resin-coated Dental Ceramic  

Microsoft Academic Search

Resin luting all-ceramic restorations increases clinical performance; however, the strengthening mechanisms are not fully understood. The authors have previously proposed the existence of a resin-ceramic hybrid layer, and the hypothesis tested was that ceramic strength enhancement was conferred by the characteristics of the resin-ceramic hybrid layer. Dentin porcelain discs were polished with a P4000-grade abrasive paper, and half were centrally

O. Addison; P. M. Marquis; G. J. P. Fleming

2008-01-01

235

Hydrolyzable polyester resins, varnishes and coating compositions containing the same  

DOEpatents

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.

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

1984-01-01

236

Synthesis and Characterization of Dicyclopentadiene – cresol Epoxy Resin  

Microsoft Academic Search

Summary  Starting from cresol, the synthesis of dicyclopentadiene (DCPD) – cresol epoxy resin was conducted. DCPD-containing phenol\\u000a resin (DPR) was prepared via Friedel–Crafts alkylation, whereas DCPD-containing epoxy resin (DER) was prepared via epoxidation\\u000a of DPR with epichlorohydrin. The chemical structure was characterized with FTIR and 1HNMR. Cure behaviors and glass transition temperature (Tg) of the resulting polymers were studied by differential

Tao Wang; Ping Y. Wan; Qin P. Yu; Meng Yu

2008-01-01

237

Method of treating wells using resin-coated particles  

SciTech Connect

The treatment of subterranean, hydrocarbon-bearing formations is discussed. A well treatment method is described which employs resin-coated particulate material. Particles coated with a fusible thermosetting resin are placed in the vicinity of a well bore and in conjunction with a subterranean formation surrounding the well bore. They are cured in the presence of a treating solution containing a softening agent capable of reducing the fusion temperature of the resin. 12 claims.

Graham, J.W.; Sinclair, A.R.; Brandt, J.L.

1982-06-29

238

Characterization of petroleum resins by nuclear magnetic resonance spectrometry  

Microsoft Academic Search

In this paper an approach to resin structure determination using ¹H and ¹³C NMR spectrometries is presented and briefly discussed. The analyzed resin samples are prepared by catalytic and thermic polymerization of the liquid byproducts, obtained by pyrolysis of primary gasoline. The result point out the differences in resin structures depending on crude oil types as well as on the

J. Muhl; Vlasta Srica; Vida Jarm; Margita Kovac-Filipovic

1987-01-01

239

Trace metal preconcentration using a thioglycolate chelating resin  

SciTech Connect

A styrene-divinyl benzene copolymer resin (Amberlite XAD-4), modified with thioglycolate complexing groups, has been employed for the preconcentration of cadmium, zinc, lead and nickel from natural waters. The resin exhibits its strongest affinity for cadmium and lead but can be used to quantitatively remove all four metals from non-saline waters. With seawater samples, the resin is best only employed for the enrichment of cadmium and lead as the recovery of nickel and zinc from this medium is poor.

Howard, A.G.; Danilona-Mirzaians, R.

1989-01-01

240

Novel Acrylic Resin For Injection Molded Precision Lenses  

NASA Astrophysics Data System (ADS)

A novel acrylic resin has been developed for injection molded precision lenses. This resin is a copolymer of tricyclodecyl methacrylate (TCDMA) with other acrylic monomers. The novel resin, TCDMA-Acrylic copolymer has rigid, bulky cyclic hydrocarbons in the side chain so that it possesses characteristics superior to conventional acrylic resin (PMMA) in terms of low moisture absorption properties and high temperature resistance. However, like PMMA, it also provides high transparency, low birefringence, and low dispersion of refraction. Because of these characteristics, TCDMA-Acrylic copolymer is being used for precision aspheric lenses that cannot be realized by conventional optical plastics.

Kawai, Hiromasa; Kanega, Fumiaki; Kohkame, Hisashi

1988-07-01

241

Synthesis and Thermal Degradation Studies of Melamine Formaldehyde Resins  

PubMed Central

Melamine formaldehyde (MF) resins have been synthesized at different reaction temperature and pH values. Different molar ratios of melamine and formaldehyde were used to synthesize the corresponding resins. The prepared resin samples were characterized by using molecular weight determination viscometry and thermogravimetric analysis (TGA). The maximum percentage of solid content (69.7%) was obtained at pH 8.5 and 75°C temperature. The molecular weight of MF resin was increased with an increase of melamine monomer concentration. The highest residual weight 14.125?wt.% was obtained with sample 10.

Ullah, Sami; Bustam, M. A.; Nadeem, M.; Tan, W. L.; Shariff, A. M.

2014-01-01

242

Diversity matters: how bees benefit from different resin sources.  

PubMed

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

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

2014-12-01

243

Preparation of site-selective ion-exchange resins  

SciTech Connect

Ion-exchange resins were prepared by copolymerization of styrenic monomers with metal ion complex compounds bearing polymerizable ligands. Removal of the metal ions by acid washing produced sites in the resins which contained ligands configured to match the bonding characteristics of the ions used in their construction. This template procedure was performed with Ni{sup 2+} and Cu{sup 2+} ions, and comparisons were made of exchange capacities and equilibrium constants for templated and untemplated resins. Templated resins showed order of magnitude capacity preferences for the ion used in their preparation. Equilibrium constants were found to be inversely related to capacities.

Harkins, D.A.; Schweitzer, G.K. (Univ. of Tennessee, Knoxville (USA))

1991-01-01

244

High fracture toughness and high modules silicone resins  

E-print Network

Rigid silicone resins, generally referred to as polyalkylsilsesquioxanes, are an important class of hybrid thermosetting polymers with both inorganic and organic characteristics. They have superior thermal stability, heat ...

Li, Zhongtao, 1971-

2000-01-01

245

Branched polymeric media: boron-chelating resins from hyperbranched polyethylenimine.  

PubMed

Extraction of boron from aqueous solutions using selective resins is important in a variety of applications including desalination, ultrapure water production, and nuclear power generation. Today's commercial boron-selective resins are exclusively prepared by functionalization of styrene-divinylbenzene (STY-DVB) beads with N-methylglucamine to produce resins with boron-chelating groups. However, such boron-selective resins have a limited binding capacity with a maximum free base content of 0.7 eq/L, which corresponds to a sorption capacity of 1.16 ± 0.03 mMol/g in aqueous solutions with equilibrium boron concentration of ?70 mM. In this article, we describe the synthesis and characterization of a new resin that can selectively extract boron from aqueous solutions. We show that branched polyethylenimine (PEI) beads obtained from an inverse suspension process can be reacted with glucono-1,5-D-lactone to afford a resin consisting of spherical beads with high density of boron-chelating groups. This resin has a sorption capacity of 1.93 ± 0.04 mMol/g in aqueous solution with equilibrium boron concentration of ?70 mM, which is 66% percent larger than that of standard commercial STY-DVB resins. Our new boron-selective resin also shows excellent regeneration efficiency using a standard acid wash with a 1.0 M HCl solution followed by neutralization with a 0.1 M NaOH solution. PMID:22827255

Mishra, Himanshu; Yu, Changjun; Chen, Dennis P; Goddard, William A; Dalleska, Nathan F; Hoffmann, Michael R; Diallo, Mamadou S

2012-08-21

246

Oil recovery method utilizing highly oxyalklated phenolic resins  

SciTech Connect

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.

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

1989-03-21

247

40 CFR 721.10545 - Aminotriazine modified cresol novolec resin (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Aminotriazine modified cresol novolec resin (generic). 721.10545...721.10545 Aminotriazine modified cresol novolec resin (generic). (a...identified generically as aminotriazine modified cresol novolec resin (PMN P-04-313)...

2013-07-01

248

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2010 CFR

...true Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2010-04-01

249

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2011 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2011-04-01

250

21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 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...

2011-04-01

251

21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 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...

2010-04-01

252

21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.  

... 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...

2014-04-01

253

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

Code of Federal Regulations, 2012 CFR

... 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...

2012-10-01

254

21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.  

Code of Federal Regulations, 2012 CFR

... 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...

2012-04-01

255

21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.  

Code of Federal Regulations, 2013 CFR

... 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...

2013-04-01

256

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

Code of Federal Regulations, 2013 CFR

... 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...

2013-10-01

257

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

Code of Federal Regulations, 2010 CFR

... 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...

2010-10-01

258

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

Code of Federal Regulations, 2011 CFR

... 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...

2011-10-01

259

77 FR 16508 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...  

Federal Register 2010, 2011, 2012, 2013

...Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; Pesticide Active Ingredient...Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; National Emission Standards...Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; Pesticide Active...

2012-03-21

260

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

... 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...

2014-10-01

261

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

...2014-04-01 false Partial phosphoric acid esters of polyester resins. 175.260...Coatings § 175.260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified...

2014-04-01

262

21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2009-04-01 true Ethylene-methyl acrylate copolymer resins. 177...Use Food Contact Surfaces § 177.1340 Ethylene-methyl acrylate copolymer resins. Ethylene-methyl acrylate copolymer resins...

2010-04-01

263

[Polymerization of visible-light cured veneering resins. 3. Influence of conversion on the bond strength of opaque resins].  

PubMed

New light-curable adhesive opaque resins were prepared using 4-methacryloxyethyl trimellitate anhydride (4-META), triethylene glycol dimethacrylate (TEGDMA), di (methacryloxyethyl) trimethylhexamethylene diurethane (UDMA) and titanium dioxide. The purpose of this study was to investigate the relation between the conversion of opaque resins and the bond strengths. Amounts of residual monomers in the bulk-photo-polymerized resins with various compositions were determined by high-performance liquid chromatography. Shear bond strengths of light-cured opaque resins joined to surface-treated Au-Ag-Pd alloy were measured with various primers, components and curing conditions. Photo-polymerized resins which contained mehyl methacrylate (MMA) showed lower conversion compared with bifunctional methacrylate resins. Favorable shear bond strengths were obtained from TEGDMA/UDMA based opaque resins. The opaque resins without MMA bonded strongly to heated and 4-META primed Au-Ag-Pd alloy and 22-23 M Pa strengths were maintained after 20,000 thermocycles. The results revealed that the conversion of MMA with photo-initiater system was lower than that of bifunctional methacrylate, which affected bond strength of opaque resins. PMID:2489704

Yoshida, K

1989-02-01

264

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

NASA Astrophysics Data System (ADS)

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.

Nakayama, Morio

265

Characterization of Composite Fan Case Resins  

NASA Technical Reports Server (NTRS)

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.

Dvoracek, Charlene M.

2004-01-01

266

Reactive Additives for Phenylethynyl-Containing Resins  

NASA Technical Reports Server (NTRS)

Phenylethynyl-containing reactive additive (PERA) compounds and mixtures have been found to be useful for improving the processability of oligomers, polymers, co-oligomers, and copolymers that contain phenylethynyl groups. The additives can be incorporated in different forms: A solution of an amide acid or an imide of a PERA can be added to a solution of phenylethynyl-containing oligomer, polymer, co-oligomer, or copolymer; or An imide powder of a PERA can be mixed with a dry powder of a phenylethynyl-containing oligomer, polymer, co-oligomer, or copolymer. The effect of a given PERA on the processability and other properties of the resin system depends on whether the PERA is used in the amide acid or an imide form. With proper formulation, the PERA reduces the melt viscosity of the resin and thereby reduces the processing pressures needed to form the adhesive bonds, consolidate filled or unfilled moldings, or fabricate fiber-reinforced composite laminates. During thermal cure, a PERA reacts with itself as well as with the phenylethynyl-containing host resin and thereby becomes chemically incorporated into the resin system. The effects of the PERA on mechanical properties, relative to those of the host resin, depend on the amount of PERA used. Typically, the incorporation of the PERA results in (1) increases in the glass-transition temperature (Tg), modulus of elasticity, and parameters that characterize behavior under compression, and (2) greater retention of the aforementioned mechanical properties at elevated temperatures without (3) significant reduction of toughness or damage tolerance. Of the formulations tested thus far, the ones found to yield the best overall results were those for which the host resin was the amide acid form of a phenylethynyl-terminated imide (PETI) co-oligomer having a molecular weight of 5,000 g/mole [hence, designated PETI-5] and a PERA denoted as PERA-1. PETI-5 was made from 3,3',4'4'-biphenyltetracarboxylic dianhydride, 3,4'-oxydianiline (3,4'-ODA), 1,3-bis(3-aminophenoxy) benzene (1,3-APB), and 4-phenylethynylphthalic anhydride (PEPA). PERA-1 was made from 3,5-diamino- 4.-phenylethynylbenzophenon and equimolar amounts of phthalic anhydride and PEPA. To make PERA-1 in the imide form, the aforementioned ingredients were processed by refluxing in glacial acetic acid. To make the amide form of PERA-1, the ingredients were reacted in N-methyl-2-pyrrolidinone (NMP) under nitrogen at a temperature of 23 C (see figure). On the basis of the processability and other properties, a blend comprising 20 weight percent of PERA-1 and 80 weight percent PETI-5 was selected for further evaluation. Relative to neat PETI-5, the blend exhibited an increase in Tg; improved processability; and comparable values of shear strength in adhesion to titanium panels, open-hole compressive properties, compression properties after impact, and resistance to microcracking.

Connell, John W.; Smith, Joseph G., Jr.; Hergenrother, Paul M.; Rommel, Monica L.

2005-01-01

267

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

SciTech Connect

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.

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

2007-09-27

268

Process for preparing light colored petroleum resins and resins produced thereby  

Microsoft Academic Search

Petroleum resins of lightened color while retaining satisfactory melting point and compatibility are provided by a process which comprises heat soaking a petroleum cracking or reforming fraction containing cationically polymerizable hydrocarbons and from 2 to more than 0.5 weight percent of cyclodienes until the cyclodiene content is no more than 0.5 weight percent distilling said heat soaked petroleum fraction and

A. B. Small; F. M. Benitez; V. L. Hughes

1985-01-01

269

In vitro comparison of the cytotoxicity of acetal resin, heat-polymerized resin, and auto-polymerized resin as denture base materials.  

PubMed

This in vitro study aims to evaluate three different base materials (acetal, heat-polymerized, and auto-polymerized resins) on L-929 mouse fibroblast cells over 1 h-, 1-, 3-, 5-, 7-day periods. The hypothesis was that acetal resin would show higher cytotoxic effect than heat-polymerized and auto-polymerized acrylic resins, as it seems possible that residual formaldehyde might be leaching from the material into the cell culture medium. The samples were produced according to the manufacturer's protocol. Then they were placed in Dulbecco's Modified Eagle Medium/Ham's F12 (DMEM/F12) for 1 h, 1, 3, 5, 7 days. After the incubation periods, cytotoxicity of the extracts to cultured fibroblasts (L-929) was measured by MTT assay. The degree of cytotoxicity of each sample was determined according to the reference value represented by the cells with a control. Statistical significance was determined by one-way ANOVA. Tukey and Tamhane tests were used as a post-hoc method to determine differences among the groups. Statistically significant difference was found among test groups at all time incubation periods (p = 0.000). The auto-polymerized resin performed higher cytotoxic effect than heat-polymerized resin and it was statistically significant at 1-day period (p < 0.05). The highest cytotoxic effect of acetal resin was observed at 5-day incubation period. In conclusion, the hypothesis was verified, since acetal resin showed more cytotoxic effect on the 3rd, 5th, and 7th days than heat- and auto-polymerized resins. Cell survival rates (% of control) of acetal resin were 58, 54, and 60%, respectively. PMID:19637373

Ata, Secil Ozkan; Yavuzyilmaz, Hüsnü

2009-11-01

270

Studies on metal complexes of SMH resin  

Microsoft Academic Search

The nature of bonding in poly(styrene-co-maleic hydroxamic acid) resin complexes of Fe(III), Cu(II), Ni(II), and Co(II) was investigated using FT-i.r., electronic and EPR spectra. Ligand to metal bonding is through the hydroxamic acid-nitrogen. Fe(III), Co(II), and Ni(II) show octahedral geometry and Cu(II) shows a square planar geometry. Thermal decomposition studies by TG and DTA indicate catalysis of decomposition by the

Rita Mendez; K. Usha; K. K. Mohammed Yussuf; V. N. Sivasankara Pillai

1996-01-01

271

Resin catalysts and method of preparation  

DOEpatents

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.

Smith, L.A. Jr.

1986-12-16

272

Resin catalysts and method of preparation  

DOEpatents

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.

Smith, Jr., Lawrence A. (P.O. Box 34687, Houston, TX 77243)

1986-01-01

273

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

PubMed Central

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.

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

2014-01-01

274

40 CFR 414.40 - Applicability; description of the thermoplastic resins subcategory.  

...Resins Polyvinyl Acetate *Polyvinyl Acetate—PVC Copolymers *Polyvinyl Acetate Copolymers ...*Polyvinylidene-Vinyl Chloride Resins *PVC Copolymers, Acrylates (Latex) *PVC Copolymers, Ethylene-Vinyl Chloride...

2014-07-01

275

Curing kinetics of a furan resin and its nanocomposites  

Microsoft Academic Search

A furan resin was synthesized from furfural and phenol and it was expected to have similar properties to the commonly used phenolic resins because the former was obtained by the replacement of formaldehyde by furfural, reducing the dangerous formaldehyde emissions. In the present work, nanocomposites were obtained by the in situ addition of 2% of different types of clays to

Guadalupe Rivero; Valeria Pettarin; Analía Vázquez; Liliana B. Manfredi

2011-01-01

276

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 ...

277

Measuring Asphaltenes and Resins, and Dipole Moment in Petroleum Fluids  

E-print Network

Measuring Asphaltenes and Resins, and Dipole Moment in Petroleum Fluids Lamia Goual Earth Science, Palo Alto, CA 94306 A petroleum fluid can be di®ided into three types of species: asphaltenes, resins or mildly polar. The interaction among these species strongly affect asphaltene precipitation from petroleum

Firoozabadi, Abbas

278

Ant repellent resins of honeybees and stingless bees  

Microsoft Academic Search

We measured the repellent effects of plant resins against the weaver ants, Oecophylla smaragdina. The resins were the sticky bands of the dwarf honeybees, Apis florea and A. andreniformis, propolis of the Western honeybee, A. mellifera and the nest entrance tubes of the stingless bees, Tetrigona apicalis, Lepidotrigona terminata, and Tetragonula collina. A bioassay was developed for testing the effects

O. Duangphakdee; N. Koeniger; S. Deowanish; H. R. Hepburn; S. Wongsiri

2009-01-01

279

Tackification of Textile Fiber Preforms in Resin Transfer Molding  

Microsoft Academic Search

Tackified textile fiber preforms are used widely in resin transfer molding (RTM) to produce aerospace-grade composite parts. To optimize the preforming process, a thorough understanding of many important material and process issues, such as fabric formability, preform dimension control, preform permeability, fiber wetting, and tackifier compatibility with the matrix resin, is essential. These issues are investigated based on a commercial

Chih-Hsin Shih; L. James Lee

2001-01-01

280

Dienophile compounds as inhibitors of resin formation in fuels  

Microsoft Academic Search

Products from thermal processing in oil refining contain a large number of unstable compounds which are readily oxidized. These materials show low induction periods to the start of noticeable oxygen absorption and form large proportions of oxidation products - resins and solid residues. Antioxidation additives, e.g. ionol inhibit oxygen absorption, but have little influence over residue and resin-formation. At the

A. M. Danilov; Ye. L. Talisman; Ye. V. Alekseyeva

1985-01-01

281

Research Article Kinetic Study of Epoxy Resin Decomposition  

E-print Network

ether type epoxy resin from bisphenol A, E-51, was cured by methyl- hexahydrophthalic anhydride (MeResearch Article Kinetic Study of Epoxy Resin Decomposition in Near-Critical Water A diglycidyl to the saturated water vapor pressure. The kinetics study of the epoxy decomposition was also carried out

Guo, John Zhanhu

282

Sand control in wells with gas generator and resin  

SciTech Connect

This patent describes a method of treating a wellbore having formation perforations for controlling sand and other fine materials. It comprises positioning a quantity of fluid resin material in alignment with the formation perforations of the wellbore; positioning a gas generator in proximity with the fluid resin material; actuating the gas generator to increase wellbore pressure in a substantially instantaneous manner to a pressure substantially in excess of well pressure to force the fluid resin material from the wellbore into the formation perforations; and subsequently polymerizing the resin material to form a consolidated, porous, permeable matrix which retains the sand and other fine materials while permitting the flow of production fluid into the wellbore. This paper also describes a method of treating a wellbore having formation perforations for controlling sand and other fine materials. It comprises positioning a coiled tubing, having a valve and gas generator attached thereto, so that the valve is positioned in a predetermined location relative to the bottom formation perforation; injecting a predetermined amount of fluid resin material through the coiled tubing and valve into the wellbore; raising the gas generator to a position across the formation perforations and in proximity with the fluid resin material; actuating the gas generator to force the fluid resin material into the formation perforations; and thereafter polymerizing the previously fluid resin material to form a consolidated, porous, permeable matrix which retains the sand and other fine materials while permitting the flow of production fluid into the wellbore.

Dees, J.M.

1992-04-07

283

Determination of Some Color Components Present in Petroleum Resin  

Microsoft Academic Search

In a previous report, it was found that some of the color components in the starting material of petroleum resin were cyclopentadiene, methylcyclopentadiene, and their dimers. In the present study, other color components than those mentioned above and the cause of coloring petroleum resin by cyclopentadiene and methyl derivative were investigated. Norbornadiene and ethylidene norbornene were found also to be

Akira Hatano; Yoshiyukiiwase; Kenji Ashida

1978-01-01

284

Selective flotation of fossil resin from western coal  

SciTech Connect

Flotation of coal continued. Technical activities for the third quarter involved efforts by both the University of Utah and Advanced Processing Technologies, Inc. Laboratory research at the University of Utah was concerned with surface chemistry/resin characterization and the development of analytical techniques. APT's activities included proof-of-concept plant testing of the fossil resin flotation circuit. 4 figs.

Jensen, G.F.; Miller, J.D.

1991-06-04

285

Project Summary Title: EFRI-RESIN Proposal, 21st  

E-print Network

Project Summary Title: EFRI-RESIN Proposal, 21st Century National Energy and Transportation/vehicular transportation systems. The project is uniquely suitable to EFRI-RESIN as it targets two critical national, carbon, and transportation; and between prices of petroleum, natural gas, and electricity, will join

Vaswani, Namrata

286

Selective flotation of fossil resin from Western coal  

SciTech Connect

Technical activities for the fourth quarter involved efforts by both the University of Utah and Advanced Processing Technologies, Inc. Laboratory research at the University of Utah was primarily concerned with surface chemistry/resin characterization, which has emphasized Fourier transform infrared analysis in the past quarter. APT's major activities included proof-of-concept plant testing of the fossil resin flotation circuit. (VC)

Jensen, G.F.; Miller, J.D.

1991-10-15

287

Selective flotation of fossil resin from western coal  

SciTech Connect

Research continued flotation of resin from coal. This quarter laboratory research at the University of Utah was concerned with surface chemistry/resin characterization and the development of analytical techniques. APT's activities included plant construction, shake-down testing and flotation testing. Data from {sup 13}C NMR analysis is presented. 2 figs., 2 tabs.

Not Available

1991-03-15

288

Method of treating wells using resin-coated particles  

SciTech Connect

Particles coated with a fusible thermosetting resin are placed in the vicinity of a wellbore and in conjunction with a subterranean formation surrounding the wellbore and are cured in the presence of a treating solution containing a softening agent capable of reducing the fusion temperature of the resin.

Brandt, J.L.; Graham, J.W.; Sinclair, A.R.

1982-06-29

289

Radionuclide Leaching from Organic Ion Exchange Resin  

SciTech Connect

Laboratory tests were performed to examine the efficacy of leach treatments for decontaminating organic ion exchange resins (OIER), which have been found in a number of samples retrieved from K East Basin sludge. Based on process records, the OIER found in the K Basins is a mixed-bet strong acid/strong base material marketed as Purolite{trademark} NRW-037. Radionuclides sorbed or associated with the OIER can restrict its disposal to the Environmental Restoration Disposal Facility (ERDF). The need for testing to support development of a treatment process for K Basin sludge has been described in Section 4.2 of ''Testing Strategy to Support the Development of K Basins Sludge Treatment Process'' (Flament 1998). To help understand the effects of anticipated OIER elutriation and washing, tests were performed with well-rinsed OIER material from K East Basin floor sludge (sample H-08 BEAD G) and with well-rinsed OIER having approximately 5% added K East canister composite sludge (sample KECOMP). The rinsed resin-bearing material also contained the inorganic ion exchanger Zeolon-900{trademark}, a zeolite primarily composed of the mineral mordenite. The zeolite was estimated to comprise 27 weight percent of the dry H-08 BEAD G material.

Delegard, C.H.; Rinehart, D.E.

1999-04-02

290

Alternative coinitiators applicable to photocurable resin composites.  

PubMed

This review aimed to examine the evolution of the composite resins`s photoinitiator system, with emphasis on those developed in recent years. This review covered literature from 1990 to 2013 and only papers with the key words of interest were included: "coinitiators", "amines", "composite resins", "photopolymerization". The search used full-text papers from PubMed and Science Direct databasis. It was included only English papers, and meeting abstracts and short communications were excluded. Hand search of the references completed the review. A total of 29 articles were studied. Many coinitiators are being researched as an alternative to traditional tertiary amines, particularly in order to improve the physical and mechanical properties of the final polymer and its biocompatibility with oral tissues. Polymerizable amines, natural compounds, and coinitiators with low toxicity and antiseptic properties were studied, and the results found they would be promising substitutes. These materials must present appropriate concentration and reactivity to obtain adequate physical and mechanical properties and high biocompatibility. However, further in vivo studies are required to verify the performance of these alternative coinitiators in the composite materials, mainly when in contact with oral tissues and the stomatognathic system. PMID:25284513

Bittencourt, Bruna Fortes; Dominguez, John Alexis; Farago, Paulo Vitor; Pinheiro, Luis Antonio; Gomes, Osnara Maria Mongruel

2014-09-01

291

Exhausting and regenerating resin for uranium removal  

SciTech Connect

Uranium removal with chloride-form anion exchange resin was studied near Houston, Texas, where an abandoned water supply well contained 120 [mu]g/L uranium and 25 pCi/L radium. With this neutral-pH, sulfate-free water, the resin exhibited enormous capacity for the uranyl tricarbonate complex, still removing 95 percent uranium after nearly 16 months without regeneration and after 302,000 bed volumes of throughput. Computer predictions indicate, however, that the presence of sulfate in feedwater would significantly shorten the run length. The efficiency of uranium removal did not deteriorate at a feed pH as low as 5.6, but when the pH was lowered to 4.3. uranium removal decreased to 50 percent and the run length was shortened to 5,000 bed volumes. Results indicate that sodium chloride (NaCl) was an adequate regenerant and, within the range of 0.5 to 4.0 N, the more concentrated the NaCl, the more efficient it was.

Zhihe Zhang; Clifford, D.A. (Univ. of Houston, TX (United States). Dept. of Environmental Engineering)

1994-04-01

292

Properties of Some Toughened, Radiation Stable Epoxy Resins  

NASA Astrophysics Data System (ADS)

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.

Zhang, H.; Huang, R. J.; Li, L. F.; Evans, D.

2008-03-01

293

[Purification process of proanthrocyanidin from rapeseed with macroporous resins].  

PubMed

The characteristics of absoption and desorption of four classes (five kinds) of macroporous resins in the solution of rapeseed proanthrocyanidin were compared. The results indicated that the weak polar macroporous resins AB-8 and HPD450 were better than the other three macroporous resins in some characteristics of absorption and desorption. In this experiment, the purity of rapeseed proanthrocyanidin prepared only by AB-8 macroporous resin column was higher than only by HPD450 column. However,the yield was lower. Using two steps of purification (first HPD450 column and second AB-8 column) obtained better results. The yield and purity were 62. 5% and 84% ,respectively. After using mixed resin column (50% HPD450 and 50% AB-8), the yield and purity were 75.2% and 80.3%, respectively. The last results might be used in industry. PMID:21213547

Wu, Jian-ming; Xia, Chun-tang; Zhang, Xiao-jun; Ding, Feng

2010-08-01

294

Anion-exchange resin-based desulfurization process  

SciTech Connect

The University of Tennessee Space Institute (UTSI) has been directed to further develop an anion-exchange, resin-based desulfurization concept. It is necessary that the soluble sulfates of alkali metal sorbents be desulfurized (regenerated) and recycled to make regenerative flue gas desulfurization options more attractive. In order to achieve this, a low-temperature, low-cost desulfurization process to reactivate spent alkali metal sorbents is necessary. UTSI's anion-exchange, resin-based concept is believed to satisfy this requirement. Investigators will perform the following investigations: screening of commercially available resins; process variables study and improving resin performance; optimization of resin-regeneration; evaluation of performance enhancers; development of Best-Process Schematic and related economics; and planing for proof-of-concept (POC) scale testing. 2 refs., 3 figs., 3 tabs.

Sheth, A.C.; Strevel, S.D.

1991-01-01

295

Recovery of resins and hydrocarbons by in situ combustion of resinous coals. Part VII: in situ gasification  

Microsoft Academic Search

A liquid resin and a hydrocarbon gas may be recovered from impermeable resinous coals by contact of the coal with steam at 550 to 800°F and 200 to 14,000 lb\\/sq in gage. A porous carbonaceous residue is left, suitable for combustion in situ.

E. M. Craighead; H. Purre

1959-01-01

296

Process for preparing light colored petroleum resins and resins produced thereby  

SciTech Connect

Petroleum resins of lightened color while retaining satisfactory melting point and compatibility are provided by a process which comprises heat soaking a petroleum cracking or reforming fraction containing cationically polymerizable hydrocarbons and from 2 to more than 0.5 weight percent of cyclodienes until the cyclodiene content is no more than 0.5 weight percent distilling said heat soaked petroleum fraction and polymerizing said distilled petroleum fraction in the presence of a polymerization catalyst.

Small, A. B.; Benitez, F. M.; Hughes, V. L.

1985-12-31

297

Leaching of concrete admixtures containing thiocyanate and resin acids.  

PubMed

There is an increasing concern about the emission of pollutants during the construction and lifetime of buildings. The leaching of concrete admixtures containing thiocyanate and resin acids was studied using standard leaching tests and chemical analysis. Ecotoxicological risk was assessed for each admixture. Thiocyanate leaching from concrete, with a chlorine-free accelerating admixture, was determined by ion chromatography. Of the total amount of thiocyanate added, 6-8% was emitted within 30 d. The thiocyanate diffusion curve indicates a fast dissolution process from the surface layer, followed by a slower continuous diffusion process. Thiocyanate exhibits both acute and chronic toxicity, which makes it of immediate environmental concern. Resin acid leaching from concrete test specimens containing an admixture of air-entraining agents with tall oil was determined by solid-phase extraction, methylation, and GC/MS. Of added resin acids, 10% was emitted over 143 d. The leaching curves for the resin acids indicate a continuous diffusion that is proportional to the square root of time and follows Fick's first law of diffusion. The chemical composition of the resin acids in the leachate demonstrates degradation and rearrangement of the resin acids during diffusion. Resin acids emitted from concrete are of environmental concern because they are persistent and have the ability to bioaccumulate in aquatic organisms. PMID:11349293

Andersson, A C; Stromvall, A M

2001-02-15

298

Phosphorus-containing imide resins - Modification by elastomers  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

299

Hand/face/neck localized pattern: sticky problems--resins.  

PubMed

Plastic resin systems have an increasingly diverse array of applications but also induce health hazards, the most common of which are allergic and irritant contact dermatitis. Contact urticaria, pigmentary changes, and photoallergic contact dermatitis may occasionally occur. Other health effects, especially respiratory and neurologic signs and symptoms, have also been reported. These resin systems include epoxies, the most frequent synthetic resin systems to cause contact dermatitis, (meth)acrylics, polyurethanes, phenol-formaldehydes, polyesters, amino resins (melamine-formaldehydes, urea-formaldehydes), polyvinyls, polystyrenes, polyolefins, polyamides and polycarbonates. Contact dermatitis usually occurs as a result of exposure to the monomers and additives in the occupational setting, although reports from consumers, using the raw materials or end products periodically surface. Resin- and additive-induced direct contact dermatitis usually presents on the hands, fingers, and forearms, while facial, eyelid, and neck involvement may occur through indirect contact, eg, via the hands, or from airborne exposure. Patch testing with commercially available materials, and in some cases the patient's own resins, is important for diagnosis. Industrial hygiene prevention techniques are essential to reduce contact dermatitis when handling these resin systems. PMID:19580919

Cao, Lauren Y; Sood, Apra; Taylor, James S

2009-07-01

300

Influence of bulk-resin properties on composite properties  

SciTech Connect

Transverse cracking is a major type of damage often observed in fiber-reinforced composites. This type of cracking occurs in the plies along the fiber direction due to the load acting perpendicular to the fibers. The objective of this research was to correlate composite properties with bulk resin properties. The purpose was to determine the influence of material variables such as molecular weight of the resin, degree of cure, and resin concentration in the composite on the fracture properties. As the resin concentration increases, the composite fracture energies of all the resins employed increased. It is found that as the molecular weight of the resin increases both the bulk and the composite fracture energies increase, the rate of increase being greater in the bulk resin. This type of behavior can be attributed to a number of different mechanisms: (1) different degrees of cure, (2) residual stresses in the samples, (3) mixed adhesive and cohesive failure of the matrix, and (4) mechanical constraint of the crack tip plastic zone. This work demonstrates the factors controlling the fracture process and attributes the results to constraints on the crack-tip plastic zone by the fibers.

Sundaram, R.

1991-01-01

301

Processing of continuous fiber composites using thermoplastic polyimide matrix resins  

SciTech Connect

Composites have been produced which contain a solvent resistant polyimide matrix with favorable physical properties. The polyimide matrix resin has been designated as P12. The prepegs used to produce the composite contain a low molecular weight resin which is the polyamic acid precursor to P12. Polymerization and imidization of the precursor resin occurs in-situ during processing. Similar commercial systems are often processed in an autoclave and pressure is used at high temperatures to obtain consolidation between prepreg laminates. Pressure is generally applied after polymerization and imidization are complete and at temperatures above the melting point of the polymer. In this research a significant decrease in composite void content was obtained by applying pressure earlier in the cure. Obtaining composites with low void content with these types of systems can be difficult. This is due in part to the generation of low molecular weight reaction by products, water and methanol. High void content results in a decrease in the physical properties of the composite structure. This is especially true for fracture properties. An empirical equation was used to describe the rate of resin removal from the composite to the bleeder cloth during processing. This equation is based on Springer-Loos resin flow model. The conditions in which this model does not apply were also determined. Determining resin removal rates is helpful in producing composites with consistent fiber/resin ratios. In addition, conditions which favor void growth can be prevented.

Kranjc, M.D.

1993-01-01

302

Intermediate velocity bullet impact response of laminated glass fiber reinforced hybrid (HEP) resin carbon nano composite  

Microsoft Academic Search

In this study, five different types of six layered GFRP laminates were prepared from three types of resin systems and compared for their intermediate velocity bullet impact response. The first panel was made of epoxy resin, second one is of hybrid resin (a blend of 60% epoxy and 40% polyester) and the remaining three panels were made of hybrid resin

P. S. Venkatanarayanan; A. Joseph Stanley

303

Fast and easy GC\\/MS identification of myrrh resins  

Microsoft Academic Search

Extracts prepared from Commiphora molmol resins were analyzed by GC-MS. Twenty-two terpenoid compounds were identified in the hexane extract of the resin. Among them,\\u000a 2-acetoxyfuranodiene (9.80%), furanoeudesma-1,3-diene (8.97%), isofuranogermacrene (6.71%), epicurzerenone (3.64%), 2-methoxyfuranodiene\\u000a (2.97%), and lindestrene (2.74%) were the main compounds from the first myrrh resin (Tamar Ltd.), and furanoeudesma-1,3-diene\\u000a (20.59%), isofuranogermacrene (17.94%), 2-acetoxyfuranodiene (8.80%), 2-methoxyfuranodiene (7.33%), and lindestrene (6.24%)

L. O. Hanuš; D. Rosenthal; T. ?ezanka; V. M. Dembitsky; A. Moussaief

2008-01-01

304

Composite veneered acrylic resin provisional restorations for complete veneer crowns.  

PubMed

Restorations that are remade to improve esthetics, teeth with pronounced gingival-to-incisal color contrast, or high-value translucent teeth can limit the capability of shaded acrylic resin provisional restorations to satisfy the esthetic demands of certain patients. This article describes a procedure to incorporate a composite veneer in an acrylic resin provisional restoration. Improved optical properties of microfilled composite are combined with the excellent marginal seal and contour of acrylic resin. Precise control of color, translucency, and surface texture provide excellent interim esthetics and a better guide for the definitive prosthesis. PMID:10559721

Solow, R A

1999-11-01

305

Chromatographic zinc isotope separation by phenol formaldehyde benzo crown resin.  

PubMed

New types of phenol formaldehyde resin having benzo crown as a functional group were synthesized and applied to zinc isotope chromatographic operation. Zinc adsorption and isotope separation capacities were dramatically improved by using phenol formaldehyde benzo-15-crown-5 resin. Zinc batch adsorption tests were performed by various dehydrated organic solvents. Separation coefficient, epsilon 8.1 x 10(-4) and height equivalent to a theoretical plate (HETP) 0.105 cm for the isotopic pair of 68Zn/64Zn in phenol formaldehyde benzo-15-crown-5 resin were obtained in the case of acetone as the solvent at 298+/-1K. PMID:16499915

Ding, Xingcheng; Nomura, Masao; Suzuki, Tatsuya; Sugiyama, Yuichi; Kaneshiki, Toshitaka; Fujii, Yasuhiko

2006-04-28

306

Cryogenic compressive properties of basic epoxy resin systems  

SciTech Connect

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.

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

1985-09-01

307

Separation of 234Th from 90Y  

NASA Astrophysics Data System (ADS)

A relatively simple procedure has been developed for the determination of 90Sr in natural aqueous samples. The method consists mainly of a Fe(III)-hydroxide co-precipitation step, followed by the separation of 90Y with the mixture of yttrium-oxalate and yttrium-ammonium-oxalate salts. This method was tested using a large number of natural water samples and 234Th contamination was observed in the prepared yttrium samples. The analysis has therefore been extended to include the separation of thorium from yttrium, which is made by DOWEX-50W-X8 cation exchange resin and citric acid as chelating agent. The experience and results of this new method are discussed.

Chobola, R.; Erdös, E.; Mell, P.; Solymosi, S.; Vincze, Á.; Török, L.; Ranga, T.; Volent, G.

1999-01-01

308

Development of an optical formaldehyde sensor based on the use of immobilized pararosaniline.  

PubMed

The colorimetric indicator pararosaniline has been immobilized onto the cation-exchange resins Amberlite IRC-50, Dowex 50W-X8 and cellulose phosphate by electrostatic bonding. The reflectance of each reagent phase was measured using a bifurcated fibre-optic system and a flow cell. Pararosaniline immobilized on cellulose phosphate was found to respond to formaldehyde without requiring the addition of sulfite to develop the purple chromogen. This immobilized system demonstrated a linear response to 50-2500 micrograms of formaldehyde and had a correlation coefficient of 0.9979. Acetaldehyde and butyraldehyde did not produce any interference. However, exposure to the unsaturated aldehydes, acrolein and crotonaldehyde, gave rise to responses that were much greater than that observed with formaldehyde. PMID:8067539

Baker, M E; Narayanaswamy, R

1994-05-01

309

Oxidative degradation of 2,6-dibromophenol using anion-exchange resin supported supramolecular catalysts of iron(III)-5,10,15,20-tetrakis (p-hydroxyphenyl)porphyrin bound to humic acid prepared via formaldehyde and urea-formaldehyde polycondensation.  

PubMed

An iron(III)-porphyrin catalyst, iron(III)-tetrakis(p-hydroxyphenyl)porphyrin (FeTHP), was introduced into a humic acid via a formaldehyde or urea-formaldehyde polycondensation reaction to stabilize the catalyst. The prepared supramolecular catalysts were then attached to Dowex-22, an anion-exchange resin. The oxidation of 2,6-dibromophenol (2,6-DBP) was then used, to evaluate the catalytic activities of the supported catalysts. The supported catalyst prepared via the urea-formaldehyde polycondensation reaction showed the highest catalytic activity of all catalysts tested. However, no debromination was observed under any conditions. To examine the reusability of the supported catalysts, they were evaluated on the basis of the decrease in the percent degradation of 2,6-DBP for the number times that they could be used. To determine why the catalytic activities decreased with increasing use, the surface of the supported catalysts were observed by scanning electron microscopy and energy dispersive X-ray spectrometry (SME-EDS) after each use. The poor reusability of the supported catalysts can be attributed to the fact that 2,6-DBP and/or brominated byproducts are tightly absorbed to the catalyst in the vicinity of the active site, which leads to inactivation of the supported catalysts. PMID:20721797

Shigetatsu, Satoko; Fukushima, Masami; Nagao, Seiya

2010-10-01

310

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

PubMed Central

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

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

2014-01-01

311

Removal of radioactive materials and heavy metals from water using magnetic resin  

DOEpatents

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

Kochen, Robert L. (Boulder, CO); Navratil, James D. (Simi Valley, CA)

1997-01-21

312

Removal of radioactive materials and heavy metals from water using magnetic resin  

DOEpatents

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

Kochen, R.L.; Navratil, J.D.

1997-01-21

313

Metabolomics Reveals the Origins of Antimicrobial Plant Resins Collected by Honey Bees  

PubMed Central

The deposition of antimicrobial plant resins in honey bee, Apis mellifera, nests has important physiological benefits. Resin foraging is difficult to approach experimentally because resin composition is highly variable among and between plant families, the environmental and plant-genotypic effects on resins are unknown, and resin foragers are relatively rare and often forage in unobservable tree canopies. Subsequently, little is known about the botanical origins of resins in many regions or the benefits of specific resins to bees. We used metabolomic methods as a type of environmental forensics to track individual resin forager behavior through comparisons of global resin metabolite patterns. The resin from the corbiculae of a single bee was sufficient to identify that resin's botanical source without prior knowledge of resin composition. Bees from our apiary discriminately foraged for resin from eastern cottonwood (Populus deltoides), and balsam poplar (P. balsamifera) among many available, even closely related, resinous plants. Cottonwood and balsam poplar resin composition did not show significant seasonal or regional changes in composition. Metabolomic analysis of resin from 6 North American Populus spp. and 5 hybrids revealed peaks characteristic to taxonomic nodes within Populus, while antimicrobial analysis revealed that resin from different species varied in inhibition of the bee bacterial pathogen, Paenibacillus larvae. We conclude that honey bees make discrete choices among many resinous plant species, even among closely related species. Bees also maintained fidelity to a single source during a foraging trip. Furthermore, the differential inhibition of P. larvae by Populus spp., thought to be preferential for resin collection in temperate regions, suggests that resins from closely related plant species many have different benefits to bees. PMID:24204850

Wilson, Michael B.; Spivak, Marla; Hegeman, Adrian D.; Rendahl, Aaron; Cohen, Jerry D.

2013-01-01

314

DIPHONIX-CS : A NOVEL COMBINED CESIUM AND STRONTIUM SELECTIVE ION EXCHANGE RESIN  

Microsoft Academic Search

The recently developed Diphonix® resin contains the geminally substituted diphosphonic acid ligand chemically bonded to a styrene-divinylbenzene copolymer. The resin exhibits an extraordinarily strong affinity for actinides, especially in the terra- and hexavalent oxidation states. Therefore the resin has potential for application in TRU removal from nuclear wastes. The Diphonix-CS resin is a Diphonix-type resin that contains also phenolic groups

R. Chiarizia; E. P. Horwitz; R. A. Beauvais; S. D. Alexandratos

1998-01-01

315

21 CFR 872.3670 - Resin impression tray material.  

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670...resin impression tray material is applied to this preliminary study model to form a custom tray. This tray is then filled...

2014-04-01

316

21 CFR 177.2415 - Poly(aryletherketone) resins.  

Code of Federal Regulations, 2013 CFR

...polystyrene standards, and a minimum mid-point glass transition temperature of 142 °C, as determined by differential scanning calorimetry. (b) Optional adjuvant substances. The basic resins identified in paragraph (a) may contain optional...

2013-04-01

317

21 CFR 177.2415 - Poly(aryletherketone) resins.  

...polystyrene standards, and a minimum mid-point glass transition temperature of 142 °C, as determined by differential scanning calorimetry. (b) Optional adjuvant substances. The basic resins identified in paragraph (a) may contain optional...

2014-04-01

318

21 CFR 177.2415 - Poly(aryletherketone) resins.  

Code of Federal Regulations, 2011 CFR

...polystyrene standards, and a minimum mid-point glass transition temperature of 142 °C, as determined by differential scanning calorimetry. (b) Optional adjuvant substances. The basic resins identified in paragraph (a) may contain optional...

2011-04-01

319

21 CFR 177.2415 - Poly(aryletherketone) resins.  

Code of Federal Regulations, 2012 CFR

...polystyrene standards, and a minimum mid-point glass transition temperature of 142 °C, as determined by differential scanning calorimetry. (b) Optional adjuvant substances. The basic resins identified in paragraph (a) may contain optional...

2012-04-01

320

21 CFR 177.2450 - Polyamide-imide resins.  

...coating and heat curing at 600 °F for 15 minutes on stainless steel plates, each having such resin-coated surface...this chapter, using a plurality of spaced, coated stainless steel plates, exposed to the respective food...

2014-04-01

321

Creep behavior of epoxy resin during irradiation at cryogenic temperature  

NASA Astrophysics Data System (ADS)

Creep tests of an epoxy resin during bending and irradiation have been carried out to investigate the synergistic effects of radiation and stress on mechanical properties of the resin. Simultaneous application of stress and irradiation on the epoxy resin enhanced creep rates in comparison with the application of stress on an irradiated sample. In order to clarify the mechanism of the radiation-induced creep, measurements of solvent swelling of specimens have been performed. The swelling increased with the dose and the increase of the swelling corresponds to the increase of the chain scission. The mechanism of increased deformation of the resin during irradiation is proposed to be caused by increased chain scission following the release of the local strain energy.

Nishiura, Tetsuya; Nishijima, Shigehiro; Okada, Toichi

1999-11-01

322

21 CFR 177.2490 - Polyphenylene sulfide resins.  

Code of Federal Regulations, 2011 CFR

...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...

2011-04-01

323

Quantification and Purification of Mulberry Anthocyanins With Macroporous Resins  

PubMed Central

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

Liu, Xueming

2004-01-01

324

Modified Paving Bitumens Based on Tar and Petroleum Polymeric Resins  

Microsoft Academic Search

Modification of tar with petroleum polymeric resins yields paving-grade bitumens with enhanced cohesion. With respect to the heat resistance and other parameters, these bitumens meet the requirements of GOST (State Standard) for BND 90\\/130 paving bitumens.

V. V. Fedorov; A. M. Syroezhko; O. Yu. Begak; V. A. Proskuryakov; G. I. Borovikov

2002-01-01

325

An Engineering Evaluation of Spherical Resorcinol Formaldehyde Resin  

SciTech Connect

A small column ion exchange (SCIX) system has been proposed for removal of cesium from caustic, supernatant, and dissolved salt solutions stored or generated from high-level tank wastes at the US Department of Energy (DOE) Hanford Site and Savannah River Sites. In both instances, deployment of SCIX systems, either in-tank or near-tank, is a means of expediting waste pretreatment and dispositioning with minimal or no new infrastructure requirements. Conceptually, the treatment approach can utilize a range of ion exchange media. Previously, both crystalline silicotitanate (CST), an inorganic, nonelutable sorbent, and resorcinol-formaldehyde (RF), an organic, elutable resin, have been considered for cesium removal from tank waste. More recently, Pacific Northwest National Laboratory (PNNL) evaluated use of SuperLig{reg_sign} 644, an elutable ion exchange medium, for the subject application. Results of testing indicate hydraulic limitations of the SuperLig{reg_sign} resin, specifically a high pressure drop through packed ion exchange columns. This limitation is likely the result of swelling and shrinkage of the irregularly shaped (granular) resin during repeated conversions between sodium and hydrogen forms as the resin is first loaded then eluted. It is anticipated that a similar flow limitation would exist in columns packed with conventional, granular RF resin. However, use of spherical RF resin is a likely means of mitigating processing limitations due to excessive pressure drop. Although size changes occur as the spherical resin is cycled through loading and elution operations, the geometry of the resin is expected to effectively mitigate the close packing that leads to high pressure drops across ion exchange columns. Multiple evaluations have been performed to determine the feasibility of using spherical RF resin and to obtain data necessary for design of an SCIX process. The work performed consisted of examination of radiation effects on resin performance, quantification of cesium adsorption performance as a function of operating temperature and pH, and evaluation of sodium uptake (titration) as function of pH and counteranion concentration. The results of these efforts are presented in this report. Hydraulic performance of the resin and the use of eluant alternatives to nitric acid have also been evaluated and have been reported elsewhere (Taylor 2009, Taylor and Johnson 2009).

Birdwell Jr, Joseph F [ORNL; Lee, Denise L [ORNL; Taylor, Paul Allen [ORNL; Collins, Robert T [ORNL; Hunt, Rodney Dale [ORNL

2010-09-01

326

Evaluation of Resin Dissolution Using an Advanced Oxidation Process - 13241  

SciTech Connect

The ion-exchange resin is widely used in nuclear reactors, in cooling water purification and removing radioactive elements. Because of the long periods of time inside the reactor system, the resin becomes radioactive. When the useful life of them is over, its re-utilization becomes inappropriate, and for this reason, the resin is considered radioactive waste. The most common method of treatment is the immobilization of spent ion exchange resin in cement in order to form a solid monolithic matrix, which reduces the radionuclides release into the environment. However, the characteristic of contraction and expansion of the resin limits its incorporation in 10%, resulting in high cost in its direct immobilization. Therefore, it is recommended the utilization of a pre-treatment, capable of reducing the volume and degrading the resin, which would increase the load capacity in the immobilization. This work aims to develop a method of degradation of ion spent resins from the nuclear research reactor of Nuclear and Energy Research Institute (IPEN/CNEN-SP), Brazil, using the Advanced Oxidative Process (AOP) with Fenton's reagent (hydrogen peroxide and ferrous sulphate as catalyst). The resin evaluated was a mixture of cationic (IR 120P) and anionic (IRA 410) resins. The reactions were conducted by varying the concentration of the catalyst (25, 50, 100 e 150 mM) and the volume of the hydrogen peroxide, at three different temperatures, 50, 60 and 70 deg. C. The time of reaction was three hours. Total organic carbon content was determined periodically in order to evaluate the degradation as a function of time. The concentration of 50 mM of catalyst was the most effective in degrading approximately 99%, using up to 330 mL of hydrogen peroxide. The most effective temperature was about 60 deg. C, because of the decomposition of hydrogen peroxide in higher temperatures. TOC content was influenced by the concentration of the catalyst, interfering in the beginning of the degradation process. It was possible to correlate it with the final amount of non-degraded resins. These results show that these conditions were favorable to destroy the resins, indicating to be the AOP an effective technique to reduce the volume of the waste. (authors)

Goulart de Araujo, Leandro; Vicente de Padua Ferreira, Rafael; Takehiro Marumo, Julio [Nuclear and Energy Research Institute, Av. Lineu Prestes, 2242., Sao Paulo, SP. (Brazil)] [Nuclear and Energy Research Institute, Av. Lineu Prestes, 2242., Sao Paulo, SP. (Brazil); Passos Piveli, Roque; Campos, Fabio [The Polytechnic School of the University of Sao Paulo, Av. Prof. Almeida Prado, 83, trav.2. Sao Paulo, SP (Brazil)] [The Polytechnic School of the University of Sao Paulo, Av. Prof. Almeida Prado, 83, trav.2. Sao Paulo, SP (Brazil)

2013-07-01

327

Fluorinated diamond particles bonded in a filled fluorocarbon resin matrix  

DOEpatents

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.

Taylor, Gene W. (Los Alamos, NM); Roybal, Herman E. (Santa Fe, NM)

1985-01-01

328

Radiation degradation in EPICOR-2 ion exchange resins  

Microsoft Academic Search

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

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

1990-01-01

329

PEG-related polymer resins as synthetic supports  

Microsoft Academic Search

Combinatorial chemistry has become a significant part of the discovery and optimization process for novel drugs, affinity\\u000a ligands, and catalysts. The polymeric supports play a key role in combinatory chemistry. Therefore, various kinds of functional\\u000a polymer resins have been exploited as supports, reagents, and catalysts in organic synthesis. In comparison to the conventional\\u000a Merrifield resins, the poly(ethylene glycol) (PEG)-related polymer

Zheng Wang; RuLei Yang; JunDong Zhu; XiaoXia Zhu

2010-01-01

330

Affordable Resins and Adhesives From Optimized Soybean Varieties (ARA Program)  

SciTech Connect

The Mission of the ARA Program was to develop the Corporate Infrastructure to mass-produce new bio-based materials from Soybeans. The resins were integrated with the bio-fuels program. (1) to research, develop, and commercialize low cost adhesives and resins from soy oil and protein, the co-products of the soy bio-diesel process. (2) to study structure-functionality of soy oil and proteins at molecular and genomic levels

Dr. Richard WOol; Dr. X. Susan Sun; Rich Chapas

2004-04-21

331

Energy dependent polymerization of resin-based composite  

Microsoft Academic Search

Objective: This study explores the relationship between the extent of polymerization and the radiant energy (dose) applied during the photopolymerization of resin-based composites.Method: FTIR was used to measure the 5-min and 24-h conversion of four resin-based composites prepared in a thin film and polymerized under conditions of decreasing intensity and a constant exposure time (30s) using a tungsten halogen curing

Rolf H. Halvorson; Robert L. Erickson; Carel L. Davidson

2002-01-01

332

Assessing the aquatic hazard of commercial hydrocarbon resins  

Microsoft Academic Search

Hydrocarbon resins are used to modify polymer products to achieve desired functional properties for a diverse range of products. These complex hydrocarbon-based mixtures are typically poorly soluble in water. However, resins may leach lower-molecular-weight monomers or impurities upon contact with water, thus posing a potential hazard to the aquatic environment. The bioavailability and toxicity of leachable constituents of four solid

R. W. Woods; D. J. Letinski; E. J. Febbo; C. L. Dzamba; M. J. Connelly; T. F. Parkerton

2007-01-01

333

Characterization and fractionation by ultrafiltration of guayule resin  

E-print Network

Committee: Dr. Aydin Akgerman Dr. John Wagner Utililization of the resinous co-product from guayule rubber production would improve the overall economics of the process. The resin was characterized by gel permeation chromatography (GPC) and by infrared... BACKGROUND THEORY GEL PERMEATION CHROMATOGRAPHY ANALYSIS INFRARED SPECTROSCOPY TYPES OF MEMBRANE SEPARATION PROCESSES DIAFILTRATIO N POLYMER VS. CERAMIC MEMBRANES MICROPOROUS VS. ASYMMETRIC MEMBRANES MANUFACTURE OF TUBULAR ASYMMETRIC CERAMIC UF...

Daly, Monica Ann

2012-06-07

334

Fluorinated diamond particles bonded in a filled fluorocarbon resin matrix  

DOEpatents

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.

Taylor, G.W.; Roybal, H.E.

1983-11-14

335

Chemical modification of matrix Resin networks with engineering thermoplastics  

Microsoft Academic Search

Functionally terminated bisphenol-A polysulfone oligomers were used in the modification of Epon Resin 828\\/4,4'-diamino-diphenylsulfone (DDS) network system. Phenolic hydroxyl terminated PSF oligomers were first capped with a large excess of bisphenol-A diglycidyl ether or Epon Resin 828 at both ends and then the resulting system was cured with DDS, in a two-step process. During these studies molecular weight and the

James L. Hedrick; I. Yilgör; Garth L. Wilkes; James E. McGrath

1985-01-01

336

Effect of Bleaching on Roughness of Dental Composite Resins  

Microsoft Academic Search

This study investigated the effect of three bleaching agents (Whiteness Perfect, Whiteness Super, Whiteness HP) on roughness of three dental resin composites (Admira, Durafill VS, Gradia Direct). Twenty disk-shaped standard specimens (10 × 2 mm) of each composite material were prepared and divided into four subgroups (n = 5). In each resin composite group, the unbleached specimens served as control; the other specimens were bleached

Arife Dogan; Suleyman Ozcelik; Orhan Murat Dogan; Ihsan Hubbezoglu; Mehmet Cakmak; Giray Bolayir

2008-01-01

337

Production of polymer resins from products of secondary origin  

Microsoft Academic Search

1.A study has been made of the possibility of the polymerization of different petroleum raw material of secondary origin, including liquid products from a synthetic-rubber plant, products of deep thermal cracking and catalytic cracking, with the aim of producing synthetic resins.2.It has been shown that petroleum polymer resins can be obtained from the liquid products of a syntheticrubber plant (from

V. S. Aliev; N. B. Al'tman; L. V. Malina; G. E. Nesterenko; G. A. Iofin

1968-01-01

338

Tetrapod-like Zinc Oxide Whisker Enhancement of Resin Composite  

Microsoft Academic Search

There is an increasing demand for composite resins with both strong antibacterial activity and satisfactory mechanical properties. This study tested the hypothesis that the new antibacterial agent tetrapod-like zinc oxide whisker (T-ZnOw) could simultaneously enhance the antibacterial activity and mechanical properties of a two-component composite resin. The antibacterial activities of the materials were assessed by the broth dilution test and

L. N. Niu; M. Fang; K. Jiao; L. H. Tang; Y. H. Xiao; L. J. Shen; J. H. Chen

2010-01-01

339

Synthesis and characterization of petroleum resins with epoxy groups  

Microsoft Academic Search

.   \\u000a Pyrolysis of petroleum hydrocarbons (including diesel pyrolysis) aimed at obtaining polyethylene also creates certain liquid\\u000a products which can be used for making so-called petroleum resins (PRs). The C9 fraction from pyrolysis contains among others, styrene and its derivatives, indene and pentanodiene. Petroleum resins with\\u000a epoxy groups (PREs) have been synthesized by oligomerization of unsaturated components of the C9

Michael Bratychak; Witold Brostow; Oleg Grynyshyn; Olena Shyshchak

2003-01-01

340

Usage of Fiber-Reinforced Resin Instruments in Interproximal Surfaces  

PubMed Central

Objectives The aim of this study was to investigate the effects of fiber-reinforced resin burs on the surface roughness of a nanofilled composite. Methods Average surface roughness values (Ra, ?m) were measured using a surface profilometer and surface textures after finishing procedures were evaluated using a scanning electron microscope (SEM). Thirty cylindrical specimens were prepared using sectional teflon molds. A nanofilled composite was chosen. After the preparation specimens were divided into three subgroups randomly. After profilometric measurements, representative samples of the mentioned finishing procedures were selected and SEM analyses were carried out. Results Mylar strip group was statistically different from the other two groups (P<.05). The smoothest surfaces occurred when composite resin samples were light cured against the strips. On the other hand there was no statistical difference between fiber-reinforced resin burs and Sof-Lex discs (P>.05). For fiber-reinforced resin burs scratches and pitting which may be due to plucking of the filler particles during finishing were observed on the surface topography of the composite resin material. On the other hand, for the Sof-Lex discs although scratches were noticed on the surface topography, no pitting was observed. Conclusions Fiber-reinforced resin burs can be preferred for the grinding of composite surplus in interproximal surfaces, where the use of Sof-Lex discs can be harmful to soft tissues. PMID:19212518

Can-Karabulut, Deniz C.; Ozyurt, Perihan; Gurbuz, Ayhan; Gullu, Abdulkadir

2008-01-01

341

Long-term deterioration of composite resin and amalgam restorations.  

PubMed

Previous long-term longitudinal studies of two different methods of placing an auto-cured conventional anterior composite resin, and of a low- and a high-copper amalgam alloy, had shown similar restoration survivals despite the different resin treatment methods used or the types of amalgam alloy placed. Therefore, the aim of the present study was to assess several clinical factors or characteristics of these restorations that were believed to affect the survival of the restorative materials. The 950 composite resin and the 1042 amalgam restorations examined were placed by many operators in numerous patients attending a dental hospital. The composite resin restorations were placed using unetched- and etched-enamel-bonding treatment methods, and the amalgam restorations were polished after insertion. Clinical ratings supplemented by color transparencies were used for the assessment of four factors for the resin, and four factors for the amalgam restoration. Significant deterioration differences were found for several of the clinical factors assessed for both the two different composite resin treatment methods, and for the two different amalgam alloys, which were not directly related to the restoration survivals. PMID:1840079

Smales, R J

1991-01-01

342

Evaluation of commercial resins for fructo-oligosaccharide separation.  

PubMed

Fructo-oligosaccharides (FOS) produced by fermentative processes are obtained in mixtures containing significant amounts of salts and other non-prebiotic sugars. A demineralisation process using a mixture of a cationic and an anionic resin was proposed. The separation of FOS from a mixture of fructose, glucose and sucrose was evaluated. Experiments were conducted with several commercial cationic exchange resins in calcium, sodium and potassium forms packed in preparative columns (7cm×2.2cm length×diameter). Resins in potassium form obtained the higher retention factor values for sugars when compared to the other ionic forms. However, when compared to calcium and sodium ones, resins in potassium cationic forms were shown to be the less efficient separating sugar mixtures. The resin with best separation performance was the Diaion UBK535Ca. A recovery yield of 92% (w/w) of FOS with 90% (w/w) of purity was obtained from batch experiments conducted in a single column loaded with the Diaion UBK535Ca resin at 25°C. The temperature shown did not influence the separation performance significantly. By increasing the column length, the purity of FOS increased to 92% (w/w), however the recovery yield decreased to 88% (w/w). PMID:23806732

Nobre, C; Suvarov, P; De Weireld, G

2014-01-25

343

Biomimetic Remineralization of Resin-bonded Acid-etched Dentin  

PubMed Central

Degradation of denuded collagen within adhesive resin-infiltrated dentin is a pertinent problem in dentin bonding. A biomimetic remineralization scheme that incorporates non-classic crystallization pathways of fluidic amorphous nanoprecursors and mesoscopic transformation has been successful in remineralizing resin-free, acid-etched dentin, with evidence of intrafibrillar and interfibrillar remineralization. This study tested the hypothesis that biomimetic remineralization provides a means for remineralizing incompletely infiltrated resin-dentin interfaces created by etch-and-rinse adhesives. The remineralization medium consists of a Portland cement/simulated body fluid that includes polyacrylic acid and polyvinylphosphonic acid biomimetic analogs for amorphous calcium phosphate dimension regulation and collagen targeting. Both interfibrillar and intrafibrillar apatites became readily discernible within the hybrid layers after 2-4 months. In addition, intra-resin apatite clusters were deposited within the porosities of the adhesive resin matrices. The biomimetic remineralization scheme provides a proof-of-concept for the adoption of nanotechnology as an alternative strategy to extend the longevity of resin-dentin bonds. PMID:19734458

Tay, F.R.; Pashley, D.H.

2009-01-01

344

Resin transfer molding of textile preforms for aircraft structural applications  

NASA Technical Reports Server (NTRS)

The NASA LaRC is conducting and supporting research to develop cost-effective fabrication methods that are applicable to primary composite aircraft structures. One of the most promising fabrication methods that has evolved is resin transfer molding (RTM) of dry textile material forms. RTM has been used for many years for secondary structures, but has received increased emphasis because it is an excellent method for applying resin to damage-tolerant textile preforms at low cost. Textile preforms based on processes such as weaving, braiding, knitting, stitching, and combinations of these have been shown to offer significant improvements in damage tolerance compared to laminated tape composites. The use of low-cost resins combined with textile preforms could provide a major breakthrough in achieving cost-effective composite aircraft structures. RTM uses resin in its lowest cost form, and storage and spoilage costs are minimal. Near net shape textile preforms are expected to be cost-effective because automated machines can be used to produce the preforms, post-cure operations such as machining and fastening are minimized, and material scrap rate may be reduced in comparison with traditional prepreg molding. The purpose of this paper is to discuss experimental and analytical techniques that are under development at NASA Langley to aid the engineer in developing RTM processes for airframe structural elements. Included are experimental techniques to characterize preform and resin behavior and analytical methods that were developed to predict resin flow and cure kinetics.

Hasko, Gregory H.; Dexter, H. Benson; Weideman, Mark H.

1992-01-01

345

Dienophile compounds as inhibitors of resin formation in fuels  

SciTech Connect

Products from thermal processing in oil refining contain a large number of unstable compounds which are readily oxidized. These materials show low induction periods to the start of noticeable oxygen absorption and form large proportions of oxidation products - resins and solid residues. Antioxidation additives, e.g. ionol inhibit oxygen absorption, but have little influence over residue and resin-formation. At the same time these processes take place vigorously during oxidation of products from vigorous oil refining processes thermal cracking, coking, pyrolysis, etc., which hinders their extensive introduction into fuels. Various mechanisms of addition are proposed to control resin- and residue-formation: dispersing, so-called screening and metal passivators. All these have a certain effect, but (except for the last-named) they do not prevent the formation of oxidation products transferring them instead into dissolved, or dispersed states in the fuel. The formation of residues and resins may not be linked with the absorption of noticeable amounts of oxygen therefore, conventional antioxidizing additives are often ineffective. Sequences of oxidative polymerization (polycondensation) are assumed to take place in the presence of traces of oxygen and result in resin-formation. Such processes are initiated by dienes, a small but sufficient proportion of which is present in products from degrative petroleum processing. If this is the case, resin formation may be precluded by introducing into the fuel particular compounds - dienophiles, which can react with dienes, forming adducts inactive toward oxidation. The possibility of using such additives is examined in this paper.

Danilov, A.M.; Talisman, Ye.L.; Alekseyeva, Ye.V.

1985-01-01

346

Flame-retardant Elvacite Acrylic Resin Nanocompoistes Using Melt Blending  

NASA Astrophysics Data System (ADS)

Flame retardant Elvacite acrylic resin/clay nanocomposites were prepared via direct melt intercalation by using a Brabender twin-screw extruder. The TEM results indicate a high degree of exfoliation occurs, 62.5exfoliated, 37.5platelets. This high degree of exfoliation results in a large improvement in thermal stability and UV resistance. The Cone Calorimetry test data show the heat release rate (HRR) and mass loss rate (MLR) of clay/Elvacite acrylic resin nanocompoistes are reduced by a factor of 2.1 and 2.2 compared to pure resins, which are consistent with a dramatic increase in the specific heat of nanocomposites as determined from high precision differential scanning calorimetry (DSC) measurements. And thermal gravimetric analysis (TGA) measurement indicates the thermal stability of nancomposites is enhanced by almost 50 ¡ãC (at 50weight loss) when the samples are thermally degraded under nitrogen. That strongly proves that the introduction of clay can dramatically improve the flame retardance of Elvacite acrylics resins. The Elvacite acrylic resin/clay nanocomposites made by this method don't have a flash point and burn gradually. And the Young's modulus of nanocomposites measured by dynamic mechanical analyzer (DMA) is higher then pure resins, especially in the molten state, which makes this new material much easier to process and mold.

Hefter, Jonathan; Song, Andrew; Si, Mayu; Rafailovich, Miriam; Sokolov, Jonathan; Goldman, Michael; Smith, Michael; Rudomen, Gregory

2003-03-01

347

Direct composite resin layering techniques for creating lifelike CAD/CAM-fabricated composite resin veneers and crowns.  

PubMed

Direct composite resin layering techniques preserve sound tooth structure and improve function and esthetics. However, intraoral placement techniques present challenges involving isolation, contamination, individual patient characteristics, and the predictability of restorative outcomes. Computer-aided design and computer-aided manufacturing (CAD/CAM) restorations enable dentists to better handle these variables and provide durable restorations in an efficient and timely manner; however, milled restorations may appear monochromatic and lack proper esthetic characteristics. For these reasons, an uncomplicated composite resin layering restoration technique can be used to combine the benefits of minimally invasive direct restorations and the ease and precision of indirect CAD/CAM restorations. Because most dentists are familiar with and skilled at composite resin layering, the use of such a technique can provide predictable and highly esthetic results. This article describes the layered composite resin restoration technique. PMID:24680167

LeSage, Brian

2014-07-01

348

[Studies of dental methacrylic resin. (Part. 6) Adhesive strength of self-curing methacrylic resin to polymethylmetacrylates with various cross-linking density. (author's transl)].  

PubMed

The adhesive property of dental acrylic resin to resin teeth and denture base resins is an important property, in the case of preperating, repairing and rebasing denture. Then, as models of denture base resin and resin tooth, heat-curing methacrylic resins which were cross-linked with three kinds of polyethylene glycol dimethacrylate, i.e., EDMA, tri-EDMA, nona-EDMA, were prepared, and the tensile adhesive strengths of self-curing methacrylic resin to them were examined. The results were as follows. 1) The tensile adhesive strength under the dry condition was dependent on cross-linking density of adherent resin, and decreased according to the increase of concentration of cross-linking agent added in adherent resin. 2) The greater the number of chain members of cross-linking agent used to adherent resin was, the higher the adhesive strength was. In particular, the adhesive strength to adherent resin added with nona-EDMA in concentration from 16.7 to 30 mole%, agreed with the tensile strength of adherent resin itself indicating a favourable adhesion. 3) The adhesive strengths under the wet condition, that is, when specimens were immersed in water at 37 degrees C for 21 days, decreased from 30 to 50%, compared with that under the dry condition. PMID:290711

Hirasawa, T; Hirabayashi, S; Harashima, I

1979-04-01

349

Development of Resin Disc Soil Testing in Rice Crop in Relation to Kinetics of Nutrient Adsorption on Resin  

Microsoft Academic Search

The aim of this investigation was to develop a durable, rigid, and reusable resin disc for soil testing with the hypothesis that a uniformly shaped disc of cation\\/anion exchange resin placed in direct contact with the soil will accumulate ions from the soil by processes similar to those for living plant roots in the natural soil–solution–plant continuum. To develop regression

Samar Chandra Datta; Sunil Kumar Singhal; Debashish Mandal

2012-01-01

350

Bonding orthodontic acrylic resin to enamel.  

PubMed

Bonded acrylic orthodontic appliances are a recent alternative to banded methods. However, the physical properties demonstrated by bonding adhesives at the acrylic-enamel interphase have not been well documented. The purpose of this study was to use a laboratory testing model to evaluate the ultimate shear and tensile strengths and fracture sites of five bonding adhesives: unfilled (Bracketbond and Genie); filled (Unite, Excel, and Concise). One hundred bovine mandibular incisors were embedded in dental stone, labial surfaces ground flat for uniform acrylic-enamel adaptation, and stored in modified Fusyama's artificial saliva. Twenty 7-mm diameter acrylic cylinders were bonded in each group. Ten samples from each group were tested for shear strength and ten for tensile strength with an Instron testing machine. Bonding adhesive retained on the cylinder was measured by means of a Bioquant digitizer. Scanning electron microscopy was used to analyze fracture sites. The results showed that the percentage of bonding adhesive that remains on the acrylic surface after fracture is decreased by the addition of inorganic fillers to the adhesive and the use of separate liquid resin sealants, and is increased by the use of plastic bracket primers and bonding adhesives that are chemically similar to methylmethacrylate. Few significant differences in shear and tensile strengths were found among the bonding adhesives. Unfilled bonding adhesives cause less enamel damage and are indicated for clinical bonding of acrylic orthodontic appliances to enamel. PMID:3287897

Eversoll, D K; Moore, R N

1988-06-01

351

Resinous binders for coal and chars  

SciTech Connect

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.

Olson, E.S.; Sharma, R.K.; Young, B.C. [Univ. of North Dakota, Grand Forks, ND (United States)

1995-12-31

352

Light color, low softening point hydrocarbon resins  

SciTech Connect

This patent describes a hydrocarbon resin having a softening point of from 0{degrees} C to about 40{degrees} C, a Gardner color of about 7 or less, a number average molecular weight (Mn) of from about 100 to about 600, and a M{sub {ital w}}/M{sub {ital n}} ratio of from about 1.1 to about 2.7, prepared by Friedel Crafts polymerization of a hydrocarbon feed. It comprises: from about 5% to about 75% by weight of a C{sub 8} to C{sub 10} vinyl aromatic hydrocarbon stream; up to about 35% by weight of a piperylene stream; and from about 25% to about 70% by weight of a stream containing C{sub 4} to C{sub 8} monoolefin chain transfer agent of the formula RR{prime}C {double bond} CR{double prime}R triple{prime} where R and R{prime} are C{sub 1} to C{sub 5} alkyl, R{double prime} and R triple{prime} are independently selected from H and a C{sub 1} to C{sub 4} alkyl group.

Evans, M.L.; Hentges, S.G.

1990-06-12

353

Platinum cluster catalysts supportedon porous chelate resin-metal complexes: Effect of resin porosity on catalytic activity  

SciTech Connect

Porous chelate resin-metal complexes were prepared from a commercial chelate resin having iminodiacetic acid moieties. This was accomplished by complexing with multivalent cations such as Al{sup 3+} and drying after washing with ethanol. The supported platinum cluster catalysts, formed by reducing the platinum ions on the porous chelate resin-metal complexes, had a mean diameter of 26 {Angstrom}, occupying pores approximately 40 {Angstrom} in diameter of the chelate resin-metal complexes. These systems were then used as catalysts during the hydrogenation of olefin or diene. The catalytic activity was found to depend on the type of metal ion used in the chelate resin-metal complexes, and it increased in the order of Na{sup +} < Mg{sup 2+} < Al{sup 3+}. The surface area of the chelate resin-metal complex, measured by a BET method, also increased in the same order, suggesting that the surface area is related to the catalytic activity. 23 refs., 6 figs., 3 tabs.

Toshima, Naoki; Teranishi, Toshiharu; Asanuma, Hiroyuki [Univ. of Tokoyo, Hongo, Bunkyo-ku (Japan)] [and others

1992-04-30

354

Contributions of the network structure to the cure kinetics of epoxy resin systems according to the change of hardeners  

Microsoft Academic Search

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

Whan Gun Kim; Jun Young Lee

2002-01-01

355

Denitration of Rocky Flats Ion-Exchange Resins: Recommendation of Denitration Processes, October 19, 1995  

SciTech Connect

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.

Jacob Espinoza; Mary Barr; Wayne Smith

1998-12-01

356

Evaluation of Cellular Toxicity of Three Denture Base Acrylic Resins  

PubMed Central

Objective This study aimed to evaluate the cellular toxicity of two newly-released acrylic resins (Futura Gen and GC Reline Hard) in comparison with the conventional heat-cure resin (Meliodent). Materials and Methods: Sample discs from each acrylic resin were placed in 24-well culture plates along with L929 mouse fibroblast cell line. A mixture of the RPMI 1640 medium, antibiotics and 10% FBS was added to the plates and the specimens were incubated in a CO2 incubator. The amount of light absorption by each plate was determined after 1 hour, 24 hours and 1 week by the MTT assay and ELISA. The cytotoxic effect of the resins was compared among groups using the two-way ANOVA and further paired comparison was performed using the post-hoc Tukey’s test. Results: After 1 hour, Futura Gen displayed a significantly lower level of light absorption in comparison with Meliodent (P=0.03). After 24 hours, GC Reline Hard rendered a significantly lower level of light absorption compared to Meliodent (P=0.02). After one-week of incubation, the mean absorption rates for GC Reline Hard, Meliodent and Futura Gen were relatively similar (P>0.05). The lowest and highest level of cytotoxicity among all resins were observed after one week and 1 hour of immersion in water, respectively. Conclusion: All the tested resins induced some degree of cytotoxicity. Cytotoxicity of Futura Gen, GC Reline Hard and Meliodent resins failed to show any significant reduction from 24 hours to one week. Thus, it is recommended to immerse the dentures in water for 24 hours prior to delivery to the patient. PMID:23323179

Ebrahimi Saravi, M.; Vojdani, M.; Bahrani, F.

2012-01-01

357

Dynamic and static mechanical analysis of resin luting cements.  

PubMed

Various types of indirect restorations are available for dental treatment and resin cements are commonly used as a luting medium. The aim of this study was to evaluate the mechanical properties of contemporary resin luting agents under different testing conditions and temperatures. The materials tested were Choice 2 (CH), Clearfil Esthetic Cement (EC), Resicem (RC) and RelyX Unicem (RX). Each material was examined after 24 h of storage at 21 °C dry and wet at 21, 37 and 50 °C under dynamic and static testing and parameters such as shear and flexural modulus, loss tangent, dynamic viscosity and Poisson's ratio were calculated. The resin cements were also subjected to creep testing under different constant loads for 3 h and a recovery time of 50 h. The material with the highest modulus was CH, while RX had the lowest. All resin cements were affected by the presence of water with RX being the least affected and by the increase of temperature, with RC being the least susceptible. None of the materials exhibited full recovery after creep testing and permanent deformation ranged from 0.43% to 5.53%. The resin cements tested in this study showed no major transitions under the different testing conditions. Their behavior was satisfactory for restorations that do not require increased mechanical properties. However, in the case of stress-bearing restorations the conditions in the oral cavity may affect the performance of these materials. PMID:22301168

Tolidis, K; Papadogiannis, D; Papadogiannis, Y; Gerasimou, P

2012-02-01

358

Characterization and Process Development of Cyanate Ester Resin Composites  

SciTech Connect

Cyanate ester resins offer advantages as composite matrices because of their high thermal stability, low outgassing, low water absorption, and radiation resistance. This paper describes the results of a processing study to develop a high-strength hoop-wound composite by the wet-filament winding method using Toray TI 000G carbon fiber and YLA RS- 14A cyanate ester resin as the constituent materials. 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 and during cure is also crucial as it affects the glass transition temperature of the resin and composite. Composite cylinders wound and cured with these methods yielded excellent ring tensile strengths both at room and elevated temperature. A summary of the measured mechanical and thermal property data for these composites is presented. Potential applications for these materials include flywheeI energy storage systems for space and satellite structures.

Frame, B.J.

1999-05-23

359

Cariogenic Bacteria Degrade Dental Resin Composites and Adhesives  

PubMed Central

A major reason for dental resin composite restoration replacement is related to secondary caries promoted by acid production from bacteria including Streptococcus mutans (S. mutans). We hypothesized that S. mutans has esterase activities that degrade dental resin composites and adhesives. Standardized specimens of resin composite (Z250), total-etch (Scotchbond Multipurpose, SB), and self-etch (Easybond, EB) adhesives were incubated with S. mutans UA159 or uninoculated culture medium (control) for up to 30 days. Quantification of the BisGMA-derived biodegradation by-product, bishydroxy-propoxy-phenyl-propane (BisHPPP), was performed by high-performance liquid chromatography. Surface analysis of the specimens was performed by scanning electron microscopy (SEM). S. mutans was shown to have esterase activities in levels comparable with those found in human saliva. A trend of increasing BisHPPP release throughout the incubation period was observed for all materials and was more elevated in the presence of bacteria vs. control medium for EB and Z250, but not for SB (p < .05). SEM confirmed the increased degradation of all materials with S. mutans UA159 vs. control. S. mutans has esterase activities at levels that degrade resin composites and adhesives; degree of degradation was dependent on the material’s chemical formulation. This finding suggests that the resin-dentin interface could be compromised by oral bacteria that contribute to the progression of secondary caries. PMID:24026951

Bourbia, M.; Ma, D.; Cvitkovitch, D.G.; Santerre, J.P.; Finer, Y.

2013-01-01

360

Copper and boron fixation in wood by pyrolytic resins.  

PubMed

A phenol-formaldehyde (PF)-resin designed to penetrate wood and immobilize copper and boron in wood cells for protection against decay was investigated. The phenol portion of the PF-resin was partially substituted with pyrolysis oil derived from softwood bark. The objective was to reduce the environmental impact associated with the production of petroleum-borne phenol, as well as to improve the product economics. Leaching tests were conducted with three different formulas of resins containing 50%, 75% or 85% by weight of pyrolytic oil on a total phenol basis. The leachates were analyzed for the presence of copper by atomic absorption spectroscopy while inductively coupled plasma spectroscopy was used for boron detection. Copper leaching was reduced up to 18 times when comparing the treatments with and without the resin. Preservative leaching varied between wood species as well as between the resins containing different concentrations of pyrolytic oil. The organic leachates were measured using gas chromatography and mass spectroscopy. Trace amounts of organics, mostly acetic acid, were found in the leachates. PMID:18835155

Mourant, Daniel; Yang, Dian-Qing; Lu, Xiao; Riedl, Bernard; Roy, Christian

2009-02-01

361

40 CFR 63.5734 - What standards must I meet for resin and gel coat application equipment cleaning operations?  

Code of Federal Regulations, 2010 CFR

...What standards must I meet for resin and gel coat application equipment cleaning operations...Manufacturing Standards for Resin and Gel Coat Application Equipment Cleaning Operations...What standards must I meet for resin and gel coat application equipment cleaning...

2010-07-01

362

40 CFR 63.5737 - How do I demonstrate compliance with the resin and gel coat application equipment cleaning...  

Code of Federal Regulations, 2010 CFR

...demonstrate compliance with the resin and gel coat application equipment cleaning standards...Manufacturing Standards for Resin and Gel Coat Application Equipment Cleaning Operations...demonstrate compliance with the resin and gel coat application equipment cleaning...

2010-07-01

363

Quantitative analysis of PMR-15 polyimide resin by HPLC  

NASA Technical Reports Server (NTRS)

The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

Roberts, Gary D.; Lauver, Richard W.

1987-01-01

364

Epoxy foams using multiple resins and curing agents  

DOEpatents

An epoxy foam comprising a plurality of resins, a plurality of curing agents, at least one blowing agent, at least one surfactant and optionally at least one filler and the process for making. Preferred is an epoxy foam comprising two resins of different reactivities, two curing agents, a blowing agent, a surfactant, and a filler. According to the present invention, an epoxy foam is prepared with tailorable reactivity, exotherm, and pore size by a process of admixing a plurality of resins with a plurality of curing agents, a surfactant and blowing agent, whereby a foamable mixture is formed and heating said foamable mixture at a temperature greater than the boiling temperature of the blowing agent whereby said mixture is foamed and cured.

Russick, Edward M. (Rio Rancho, NM); Rand, Peter B. (Albuquerque, NM)

2000-01-01

365

[Treatment of sulfanilamide production wastewater by resin adsorption technique].  

PubMed

According to the character of sulfanilamide production wastewater, in this paper, the recovery process of sulfanilamide, sodium nitrate in wastewater resulting from manufacturing sulfanilamide was developed by using macro porous resin. The conditions of the resin adsorption and desorption capacity were investigated and the optimal parameters were determined. The results of experiment indicated that this technique was suitable for removal of sulfanilamide from wastewater. About 86% COD removal was obtained under the optimized adsorption conditions, about 86% sulfanilamide and 95% sodium nitrate were recovered from wastewater for possible recycling to the manufacturing process and the recovered sulfanilamide's purity reached 99.8%. The adsorption capacity of resin remained constant during the repetition process of adsorption and desorption. This technique not only eliminates the environmental pollution but also obtain distinct economic benefit. PMID:14768582

Xu, Yueqing; Peng, Yingdeng; Zhao, Renxing

2003-11-01

366

Dental fiber-post resin base material: a review.  

PubMed

Teeth that have short clinical crown, which are not alone enough to support the definitive restoration can be best treated using the post and core system. The advantages of fiber post over conventional metallic post materials have led to its wide acceptance. In addition to that the combination of aesthetic and mechanical benefits of fiber post has provided it with a rise in the field of dentistry. Also the results obtained from some clinical trials have encouraged the clinicians to use the fiber posts confidently. Fiber posts are manufactured from pre-stretched fibers impregnated within a resin matrix. The fibers could that be of carbon, glass/silica, and quartz, whereas Epoxy and bis-GMA are the most widely used resin bases. But recently studies are also found to be going on for polyimide as possible material for the fiber post resin base as a substitute for the conventional materials. PMID:24605208

Lamichhane, Aashwini; Xu, Chun; Zhang, Fu-Qiang

2014-02-01

367

Characterization of non-MDA-containing bismaleimide resins  

SciTech Connect

Recent regulatory action by OSHA for the workplace exposure to 4,4'-methylenedianiline (MDA) is generating considerable interest in developing non-MDA-containing thermoset resins. One such material is a new bismaleimide, 2,2'-bismaleimido(1,2 phenylthioethane), designated APO-BMI. This material has been evaluated and pilot production quantities produced for replacement of a commercially available MDA-containing bismaleimide for syntactic foam applications. A diol extended version of the APO-BMI has also been characterized. Thermal analysis has been used extensively to characterize these three materials. Comparative data for these three resins will be presented and will include cure cycle optimization, glass transition and resin reactivity measurements by DSC, thermal and oxidative stability by TGA and coefficient of linear thermal expansion and Tg by TMA. 2 refs., 7 figs.

Spieker, D.A.; Larsen, F.N.

1988-08-01

368

Raman spectroscopic studies of acid dissociation in sulfonated polystyrene resins  

NASA Astrophysics Data System (ADS)

FT-Raman spectra of sulfonated polystyrene resins with varying levels of sulfonation from 9-97% have been recorded. Molecular markers of -SO 3H and -SO 3- moieties have been proposed and used to determine quantitatively the degree of dissociation of the acids as a function of total sulfonic acid and sulfonate concentrations. Comparison with the ethanesulfonic acid/water system has been made and it is concluded that the low-sulfonation and high-sulfonation resins closely resemble this molecular acid/water system, but that intermediate sulfonation specimens are dissociated some 18% less than the corresponding ethanesulfonic acid/water analogues. This is ascribed to the presence of hydrogen-bonded acid groups with water in the gel region of the resins which had been suggested in previous infrared spectroscopic measurements.

Edwards, H. G. M.; Brown, D. R.; Dale, J. R.; Plant, S.

2001-09-01

369

White-rot fungi demonstrate first biodegradation of phenolic resin.  

PubMed

Phenolic resins, phenol-formaldehyde polymers previously thought to be nonbiodegradable, are produced at an annual rate of 2.2 million metric tons in the United States for many industrial and commercial applications. Three independent lines of evidence established their biodegradability with the white-rot fungus Phanerochaete chrysosporium. Chromatic transformation of growth medium (yellow to pink) indicated initial biodegradation of the resin 3 days after inoculation. A degradation product, 13C-labeled phenol, was detected with gas chromatography-mass spectroscopy. Scanning electron micrographs revealed physical evidence of degradation. This is the first demonstrated biodegradation of these phenol-formaldehyde polymers and stands as a platform for investigation into bioremediation and biorecycling of phenolic resins. PMID:16856735

Gusse, Adam C; Miller, Paul D; Volk, Thomas J

2006-07-01

370

Dental fiber-post resin base material: a review  

PubMed Central

Teeth that have short clinical crown, which are not alone enough to support the definitive restoration can be best treated using the post and core system. The advantages of fiber post over conventional metallic post materials have led to its wide acceptance. In addition to that the combination of aesthetic and mechanical benefits of fiber post has provided it with a rise in the field of dentistry. Also the results obtained from some clinical trials have encouraged the clinicians to use the fiber posts confidently. Fiber posts are manufactured from pre-stretched fibers impregnated within a resin matrix. The fibers could that be of carbon, glass/silica, and quartz, whereas Epoxy and bis-GMA are the most widely used resin bases. But recently studies are also found to be going on for polyimide as possible material for the fiber post resin base as a substitute for the conventional materials. PMID:24605208

Xu, Chun; Zhang, Fu-qiang

2014-01-01

371

Reactivity of Resorcinol Formaldehyde Resin with Nitric Acid  

SciTech Connect

Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. The threshold conditions promoting reaction have been identified. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.

King, William D.; Fondeur, Fernando F.; Wilmarth, William R.; Pettis, Myra E.

2005-10-25

372

REACTIVITY OF RESORCINOL FORMALDEHYDE RESIN WITH NITRIC ACID  

SciTech Connect

Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.

King, W; Fernando Fondeur, F; Bill Wilmarth, B; Myra Pettis, M; Shirley Mccollum, S

2006-06-14

373

Epoxy and acrylate sterolithography resins: in-situ property measurements  

SciTech Connect

Stereolithography is a rapid prototyping method that is becoming an important product realization and concurrent engineering tool, with applications in advanced and agile manufacturing. During the build process, material behavior plays a significant role in the mechanics leading to internal stresses and, potentially, to distortion (curling) of parts. The goal of the ``Stereolithography Manufacturing Process Modeling and Optimization`` LDRD program was to develop engineering tools for improving overall part accuracy during the stereolithography build process. These tools include phenomenological material models of solidifying stereolithography photocurable resins and a 3D finite element architecture that incorporates time varying material behavior, laser path dependence, and structural linkage. This SAND report discusses the in situ measurement of shrinkage and force relaxation behavior of two photocurable resins, and the measurement of curl in simple cantilever beams. These studies directly supported the development of phenomenological material models for solidifying resins and provided experimental curl data to compare to model predictions.

Guess, T.R.; Chambers, R.S.; Hinnerichs, T.D.

1996-01-01

374

The physical properties of a polyacetal denture resin.  

PubMed

A polyacetal injection-moulded resin is being marketed for the construction of retentive and supportive components of removable partial dentures (RPDs). Specimens of poly(oxymethylene) cast by commercial laboratories were tested to examine the following physical characteristics: the modulus of elasticity in compression, extension and flexure, stress relaxation, the force displacement behaviour of clasp forms, impact strength and glass transition temperature. Results showed that the material has a flexural modulus lower than that of poly(methylmethacrylate) and is insufficiently rigid to be used as a supporting element for partial dentures. Resin clasps may be resilient enough to engage undercuts for the retention of RPDs but the low flexural modulus requires that the resin be used in greater cross-sectional area than metal alloys in order to gain useful retention. This greater bulk has implications for plaque accumulation and maintenance of periodontal health. PMID:10150599

Fitton, J S; Davies, E H; Howlett, J A; Pearson, G J

1994-01-01

375

Synthesis, characterization and some adsorption properties of TMMA chelating resin  

NASA Astrophysics Data System (ADS)

In order to separate U(VI) ions and lanthanide ions from acidic media, N, N, N', N'-tetramethylmalonamide, (TMMA), chelating resin was synthesized by chemically bonding the functional group to the main chain of chloromethylstyrene-divinylbenzene copolymer. Characterization of the resin in terms of IR, solid-NMR, porosity and elemental analysis suggested that TMMA was uniformly linked to the polymer particles following the expected synthetic scheme and that the introduction ratio was ca. 75%. The uptake behavior of Ce(III) ions and of U(VI) ions from different acidic media were investigated using the batch technique. The kinetic and equilibrium studies showed that the obtained resin is promising for the proposed separation.

Nogami, M.; Ismail, I. M.; Yamaguchi, M.; Suzuki, K.

2003-02-01

376

Environmentally Friendly Bio-Based Vinyl Ester Resins for Military Composite Structures.  

National Technical Information Service (NTIS)

Liquid resins used for molding composite structures a significant source of volatile organic compounds (VOC) and hazardous air pollutant (HAP) emissions. One method of reducing styrene emissions from vinyl ester (VE) resins is to replace some or all of th...

D. Fudge, I. McAninch, J. J. La Scala, J. M. Sands, S. E. Boyd

2008-01-01

377

Effects of cross-sectional area on resin-enamel tensile bond strength  

Microsoft Academic Search

Objective.It was hypothesized that there is an inverse relationship between resin-enamel bond strength and bonded cross-sectional area, and that there are regional differences in resin-enamel bond strength.

Yasuo Shono; Masamichi Terashital; Edna L. Pashley; Phyllis D. Brewer; David H. Pashley

1997-01-01

378

Effect of Resins and DBSA on Asphaltene Precipitation from Petroleum Fluids  

E-print Network

of various resins and dodecyl benzene sulfonic acid (DBSA) amphiphile on asphaltene precipitation from that of resins. When the DBSA amphiphile is mixed with the petroleum fluid at different concentrations, we

Firoozabadi, Abbas

379

21 CFR 189.300 - Hydrogenated 4,4?-isopropyl-idene-diphenol-phosphite ester resins.  

Code of Federal Regulations, 2010 CFR

...4â²-isopropyl-idene-diphenol-phosphite ester resins. 189.300 Section...4?-isopropyl-idene-diphenol-phosphite ester resins. (a) Hydrogenated...condensation product of 1 mole of triphenyl phosphite and 1.5 moles of...

2010-04-01

380

21 CFR 173.70 - Chloromethylated aminated styrene-divinylbenzene resin.  

...2014-04-01 false Chloromethylated aminated styrene-divinylbenzene resin. 173.70 Section... § 173.70 Chloromethylated aminated styrene-divinylbenzene resin. Chloromethylated aminated styrene-divinylbenzene copolymer (CAS...

2014-04-01

381

21 CFR 181.26 - Drying oils as components of finished resins.  

...2014-04-01 2014-04-01 false Drying oils as components of finished resins. 181...Food Ingredients § 181.26 Drying oils as components of finished resins. Substances classified as drying oils, when migrating from...

2014-04-01

382

Investigating the Use of Ion Exchange Resins for Processing Biodiesel Feedstocks  

E-print Network

Ion exchange resins, commonly used in water treatment, demonstrate promise for the production of biodiesel from biomass feedstocks. The goal of this presented PhD research is to investigate novel uses of ion exchange resins for processing biodiesel...

Jamal, Yousuf 1973-

2012-11-27

383

Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings.  

PubMed

The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling. PMID:23101178

Tsumita, M; Kokubo, Y; Kano, T

2012-09-01

384

INDUSTRIAL PROCESS PROFILES FOR ENVIRONMENTAL USE. CHAPTER 10A. THE PLASTICS AND RESINS PROCESSING INDUSTRY  

EPA Science Inventory

The report contains a detailed analysis of the plastics and resins processing industry, which includes operations that convert polymers and resins into consumer products. Analytical elements include industry definition, raw materials, products, manufacturers, environmental impact...

385

Applications of fossil resin studies to an understanding of depositional and paleoenvironments  

SciTech Connect

Fossil resins are polymerized terpene (isoprenoid) acids. Because of their complexity and resulting variability, isoprenoids have been useful for their information content and geochemical signatures. Fossil resin occurs throughout a 304-ft continuous core and correlated outcrops from the Late Cretaceous Fruitland Formation in the Fossil Forest study area, San Juan basin, New Mexico, in associated with coal, sandstone, shale, and petrified wood. Fourier transformation infrared (FTIR) spectra of resin from throughout the sequence reveal oxidative and chemical variation. FTIR spectra of resin incorporated in petrified wood differ from those of resin exposed to the paleoatmosphere in the same individual tree. This study was initiated to complement previous studies related to analyses of fluid inclusions in fossil resin and to elucidate reactions between the resin matrix and possible atmospheric inclusions. It was done in conjunction with extensive trace-element, palynological, and mineralogical analyses. Understanding the biogeochemistry of fossil resin may elucidate the origin, diagenesis, and depositional environment of smaller concentrations of isoprenoids.

Bellis, D.; Wolberg, D.L. (New Mexico Bureau of Mines and Mineral Resources, Socorro (USA))

1989-09-01

386

40 CFR 63.5728 - What standards must I meet for closed molding resin operations?  

Code of Federal Regulations, 2010 CFR

...with the limit for open molding resin and gel coat operations specified in § 63.5698. Examples of these operations include gel coat or skin coat layers that are applied...closed molding. Standards for Resin and Gel Coat Mixing...

2010-07-01

387

40 CFR 63.5714 - How do I demonstrate compliance if I use filled resins?  

Code of Federal Regulations, 2010 CFR

...CATEGORIES National Emission Standards for Hazardous Air Pollutants for Boat Manufacturing Standards for Open Molding Resin and Gel Coat Operations § 63.5714 How do I demonstrate compliance if I use filled resins? (a) If you are using a...

2010-07-01

388

Hydrocarbon solvent recovery in the presence of resin contaminants  

SciTech Connect

A system was developed to recover acetone from an air stream in which epoxy resin particles were suspended. This recovery problem is encountered in the manufacture of fiber glass reinforced plastic pipe. It is representative of numerous other industrial situations which require the recovery of hydrocarbon solvents from a gaseous stream containing resin particles in order to eliminate atmospheric pollution. The system developed was a three-stage low temperature condensation process preceded by a cascade impactor. A scale model of the system was designed and constructed. It was tested in the laboratory, and on a split stream of an actual plant process.

Turpin, J.L.

1984-01-01

389

Characterization of selected LDEF polymer matrix resin composite materials  

NASA Technical Reports Server (NTRS)

The characterization of selected graphite fiber reinforced epoxy (934 and 5208) and polysulfone (P1700) matrix resin composite materials which received 5 years and 10 months of exposure to the LEO environment on the Long Duration Exposure Facility is reported. Resin loss and a decrease in mechanical performance as well as dramatic visual effects were observed. However, chemical characterization including infrared, thermal, and selected solution property measurements showed that the molecular structure of the polymeric matrix had not changed significantly in response to this exposure. The potential effect of a silicon-containing molecular contamination of these specimens is addressed.

Young, Philip R.; Slemp, Wayne S.; Witte, William G., Jr.; Shen, James Y.

1991-01-01

390

Quality assurance procedures for V378A matrix resin  

NASA Technical Reports Server (NTRS)

A characterization methodology has been developed on which to base quality assurance procedures for U.S. Polymeric V378A bismaleimide matrix resin. Chemical composition is established by partition reverse phase and size exclusion liquid chromatography. Cure rheology behavior is quantitatively characterized by dynamic viscoelastic analysis using the parallel plate technique. The overall cure process is characterized by differential scanning calorimetry. The sensitivity of the procedures is evaluated by studying the effects of ambient out time on the chemical end behaviorial properties of the resin.

Hamermesh, C. L.; Dynes, P. J.

1985-01-01

391

Holographic characterization of epoxy resins at 351.1 nm  

NASA Astrophysics Data System (ADS)

The optical characteristics of two commercially available UV curable epoxy resins are investigated using nondegenerate four-wave mixing. The materials assessed are optimized for use with a UV argon-ion laser. The holographic gratings were written at a wavelength of (lambda) equals 351.1 nm for an irradiance range 0.5 to 3.0 W/cm2 and read at (lambda) equals 632.8 nm to compare the reactivity, curing speed, shrinkage, and resolution of the resins. These experiments were carried out to prove the suitability of the photopolymerization systems for microstereolithography.

Farsari, Maria; Huang, Shiping; Young, Rupert C.; Heywood, Malcolm I.; Morrell, Patrick J.; Chatwin, Christopher R.

1998-10-01

392

Ultraviolet light and ultraviolet light-activated composite resins  

SciTech Connect

In a comparison of the UV light--activated composite resins, Estilux was polymerized to a significantly greater depth than the other composite resins. In general, Lee-fill polymerized the least. When comparing the UV light sources, the Lee light and the Duralux light did not significantly differ from each other, but both polymerized the materials tested to a significantly greater depth than the other light sources. Of the two time exposures, 60-second exposure provided a significantly greater depth of polymerization than 20 seconds for each light with each material.

Murray, G.A.; Yates, J.L.; Newman, S.M.

1981-08-01

393

Genotoxicity of dental resin polymerization initiators in vitro  

Microsoft Academic Search

The polymerization initiators for resins cured using visible light usually consist of a photosensitizer, primarily camphorquinone\\u000a (CQ), and a reducing agent, which is often a tertiary amine (DMPT, DMAEMA), while the initiator used for self-curing resins\\u000a consists of benzoyl peroxide (BPO) and a tertiary amine (DMPT). The genotoxicities of camphorquinone (CQ), benzoyl peroxide\\u000a (BPO), dimethyl-para-toluidine (DMPT), 2-dimethylamino-ethyl-methacrylate (DMAEMA), and 1-allyl-2-thiourea

Y. Nomura; W. Teshima; T. Kawahara; N. Tanaka; H. Ishibashi; M. Okazaki; K. Arizono

2006-01-01

394

Cobalt dicarbollide containing polymer resins for cesium and strontium uptake  

SciTech Connect

Cobalt(III) dicarbollide [(C{sub 2}B{sub 9}H{sub 11}){sub 2}Co]{sup {minus}} (CB{sub 2}) is being investigated for Cs and Sr extraction from nuclear waste. Because organic solvents should be avoided, bonding of CB{sub 2} to resins were investigated. CB{sub 2} was successfully covalently bonded to polystyrene and polybenzimidazole resins. Tetrahydrofuran was the most efficient solvent for grafting. Analysis is being performed, and separation coefficients are also being determined. 3 figs, 8 refs.

Steckle, W.P. Jr.; Duke, J.R. Jr.; Jorgensen, B.S.

1994-04-01

395

Regeneration of anion exchange resins by catalyzed electrochemical reduction  

DOEpatents

Anion exchange resins sorbed with perchlorate may be regenerated by a combination of chemical reduction of perchlorate to chloride using a reducing agent and an electrochemical reduction of the oxidized reducing agent. Transitional metals including Ti, Re, and V are preferred chemical reagents for the reduction of perchlorate to chloride. Complexing agents such as oxalate are used to prevent the precipitation of the oxidized Ti(IV) species, and ethyl alcohol may be added to accelerate the reduction kinetics of perchlorate. The regeneration may be performed by continuously recycling the regenerating solution through the resin bed and an electrochemical cell so that the secondary waste generation is minimized.

Gu, Baohua (Oak Ridge, TN); Brown, Gilbert M. (Knoxville, TN)

2002-01-01

396

A quantum chemistry study on structural properties of petroleum resin  

Microsoft Academic Search

The geometries of resins with single-layer (SG), double-layer (DG) and triple-layer (TG) were calculated with the quantum\\u000a chemistry method. The geometries and net charges of atoms were obtained. The calculated average distances between layers were\\u000a 0.5348 nm and 0.5051 nm and the action energies were ?9.6355 kJ\\/mol and ?32.2803 kJ\\/mol for resins DG and TG, respectively.\\u000a Higher electronegative polar atoms

Wang Daxi; Pan Yueqiu; Zhang Hongye

2007-01-01

397

Fluorinated epoxy resins with high glass transition temperatures  

NASA Technical Reports Server (NTRS)

Easily processed liquid resins of low dielectric constants and high glass transition temperatures are useful for the manufacture of certain composite electronic boards. That combination of properties is difficult to acquire when dielectric constants are below 2.5, glass transition temperatures are above 200 C and processability is of conventional practicality. A recently issued patent (US 4,981,941 of 1 Jan. 1991) teaches practical materials and is the culmination of 23 years of research and effort and 15 patents owned by the Navy in the field of fluorinated resins of several classes. In addition to high fluorine content, practical utility was emphasized.

Griffith, James R.

1991-01-01

398

Studies on structure and properties of CNSL novolac resins prepared with succinic acid catalyst  

Microsoft Academic Search

Cashew nut shell liquid (CNSL) was used to prepare a glass fabric laminate. Two fast curing model resins were prepared using\\u000a cardanol and formaldehyde in the presence of succinic acid catalyst. The resins possess ortho-ortho and ortho-para linkages.\\u000a The curing kinetics of the resins showed that the resin prepared with mole ratio 0·8 possesses good curing characteristics.\\u000a The IR spectra

K Sathiyalekshmi

1993-01-01

399

From vulcanite to vinyl, a history of resins in restorative dentistry  

Microsoft Academic Search

This article provides historical background on the development of resin-based dental restorative materials. With an understanding of the evolution of these materials, clinicians can better appreciate both the complexity of and similarities among the wide variety of resins and polymerization techniques available today. Common problems associated with the use of resin-based materials are explained, and more advanced resin-based systems currently

Frederick A. Rueggeberg

2002-01-01

400

Dehydration of 1-pentanol to di- n-pentyl ether over ion-exchange resin catalysts  

Microsoft Academic Search

The dehydration reaction of 1-pentanol to di-n-pentyl ether (DNPE) and water in the liquid phase was studied at 110–180°C and 1MPa on sulfonic styrene–divinylbenzene (S\\/DVB) copolymers and the perfluoroalkanesulfonic resin NR50. S\\/DVB-based catalysts were macroreticular and gel-type resins both sulfonated conventionally and oversulfonated. Macroreticular resins tested include resins whose working phase in catalysis is gel phase (i.e. Amberlyst-15 and Amberlyst-35)

J. Tejero; F. Cunill; M. Iborra; J. F. Izquierdo; C. Fité

2002-01-01

401

Novel chelating resins containing calix[4]pyrroles: Synthesis and sorptive properties  

Microsoft Academic Search

Chelating resins containing calix[4]pyrroles have been synthesized via: (i) immobilization of calixpyrrole on a polymeric support (VBC\\/DVB copolymer), (ii) condensation of calixpyrrole with formaldehyde, and (iii) radical copolymerization of calixpyrrole-monomer with methyl methacrylate and divinylbenzene. Insoluble, cross-linked material was obtained in all cases, bearing up to 1.03mmol of calixpyrrole units per gram resin in case of resin 2. All resins

Andrzej Ka??dkowski; Andrzej W. Trochimczuk

2006-01-01

402

Carrier materials impregnated with thermosetting resins, process for their manufacture and their use  

SciTech Connect

Described herein is a resin-cured carrier material and a process for preparing a resin-cured carrier material. The carrier material has two oppositely disposed major surfaces and a core therebetween, the core being impregnated with at least one heatcured thermosetting resin and at least one of the two surfaces having a coating of at least one polymerization resin curable by U.V.-radiation, electron radiation or the radiation of radioactive isotopes.

Holzer, H.; Kopp, O.; Schinko, C.B.

1981-01-20

403

New technology for separating resin powder and fiberglass powder from fiberglass-resin powder of waste printed circuit boards.  

PubMed

New recycling technologies have been developed lately to enhance the value of the fiberglass powder-resin powder fraction (FRP) from waste printed circuit boards. The definite aim of the present paper is to present some novel methods that use the image forces for the separation of the resin powder and fiberglass powder generated from FRP during the corona electrostatic separating process. The particle shape charactization and particle trajectory simulation were performed on samples of mixed non-metallic particles. The simulation results pointed out that particles of resin powder and particles of fiberglass powder had different detach trajectories at the conditions of the same size and certain device parameters. An experiment carried out using a corona electrostatic separator validated the possibility of sorting these particles based on the differences in their shape characteristics. The differences in the physical properties of the different types of particles provided the technical basis for the development of electrostatic separation technologies for the recycling industry. PMID:24678800

Li, Jia; Gao, Bei; Xu, Zhenming

2014-05-01

404

Thermoplastic Resin Sales by Major Market (millions of pounds, dry weight basis)  

E-print Network

Thermoplastic Resin Sales by Major Market 2004-2008 (millions of pounds, dry weight basis) Major selected thermoplastic resins: Low-Density Polyethylene Polyvinyl Chloride Linear-Low-Density Polyethylene-Acrylonitrile Polystyrene Other Styrene-based Polymers Styrene Butadiene Latexes (SBL) Engineering Resins Thermoplastic

Laughlin, Robert B.

405

Radiation effects on resins and zeolites at Three Mile Island Unit II  

Microsoft Academic Search

Radiation effects on resin and zeolite used in the waste cleanup at Three Mile Island Unit II have been examined both experimentally and in-situ. Hydrogen and organic gases are generated due to absorbed radiation as a function of resin material, curie loading and residual water content. Significant oxygen scavaging was demonstrated in the organic resin liners. Hydrogen and oxygen gases

J. K. Reilly; P. J. Grant; G. J. Quinn; K. J. Hofstetter

1984-01-01

406

Low-level waste data base development - EPICOR II resin\\/liner investigation - a program review  

Microsoft Academic Search

This paper presents an overview of the titled program and gives the status of the work on resin degradation, resin solidification, and field testing of solidified samples. A brief discussion of some recent results also is included. Resin materials from EPICOR-II prefilters used during cleanup of Three Mile Island Nuclear Power Station are being examined to (a) develop a data

J. W. Jr. McConnell; H. W. Reno; R. C. Schmitt; A. L. Jr. Ayers

1986-01-01

407

Low level waste data base development - EPICOR-II resin\\/liner investigation. Program review  

Microsoft Academic Search

This paper presents an overview of the titled program and gives the status of the work on resin degradation, resin solidification, and field testing of solidified samples. A brief discussion of some recent results is also included. Resin materials from EPICOR-II prefilters used in the cleanup of the Three Mile Island Nuclear Power Station are being examined to (1) develop

J. W. Jr

1985-01-01

408

Resin secretory structures of Boswellia papyrifera and implications for frankincense yield  

PubMed Central

Background and Aims Frankincense, a gum-resin, has been tapped from Boswellia papyrifera trees for centuries. Despite the intensive tapping and economic interest of B. papyrifera, information on the resin secretory structures, which are responsible for synthesis, storage and transport of frankincense, is virtually absent. This study describes the type, architecture and distribution of resin secretory structures of B. papyrifera and its relevance for the ecophysiology and economic use of the tree. Methods The type and architecture of resin secretory structures present in bark and wood was investigated from transversal, tangential and radial sections of bark and wood samples. The diameter and density (number of resin canals mm?2) of axial resin canals were determined from digital images of thin sections across the different zones of inner bark. Key Results Resin canals form a three-dimensional network within the inner bark. Yet, the intact resin-conducting and producing network is on average limited to the inner 6·6 mm of the inner bark. Within the inner bark, the density of non-lignified axial resin canals decreases and the density of lignified resin canals increases from the vascular cambium towards the outer bark. In the wood, only radial resin canals were encountered. Conclusions Frankincense tapping techniques can be improved based on knowledge of bark anatomy and distribution and architecture of resin secretory structures. The suggested new techniques will contribute to a more sustainable frankincense production that enhances the contribution of frankincense to rural livelihoods and the national economy. PMID:23223203

Tolera, Motuma; Menger, David; Sass-Klaassen, Ute; Sterck, Frank J.; Copini, Paul; Bongers, Frans

2013-01-01

409

A Numerical Study of Nonisothermal Resin Flow in RTM with Heated Uniaxial Fibers  

Microsoft Academic Search

A numerical model is developed to study the flow of a thermoset resin parallel to a unidirectional, heated fiber array, where the resin viscosity varies with temperature. Steady, incompressible flow is assumed when solving the momentum equation for the velocity parallel to the fiber tow. Resin temperatures are determined by applying a finite differencing scheme to the convective energy equation.

Scott A. Wymer; Renata S. Engel

1994-01-01

410

The adsorption of gold and copper onto ion-exchange resins from ammoniacal thiosulfate solutions  

Microsoft Academic Search

The recovery of gold and copper from ammonium thiosulfate (ATS) solutions using anion-exchange resins has been investigated using batch studies. Strongly basic resins are preferred to weakly basic resins because of their greater range of operational pH and higher loading. The kinetics and isotherms for the adsorption of gold and copper were measured. Individually, gold and copper could be loaded

Hongguang Zhang; David B Dreisinger

2002-01-01

411

EFFECTS OF RESIN AND WAX ON THE WATER UPTAKE BEHAVIOR OF WOOD STRANDS  

E-print Network

EFFECTS OF RESIN AND WAX ON THE WATER UPTAKE BEHAVIOR OF WOOD STRANDS Yang2hang1 Post February 2005) ABSTRACT Dimensional stability is an important property of wood composites. Both resin and wax are essential additives in the manufactureof composite panels such as OSB. Resin binds wood

Wang, Siqun

412

IONIC DOPING OF LOW-CONDUCTIVITY STRUCTURAL RESINS FOR IMPROVED DIRECT-CURRENT SENSING  

EPA Science Inventory

This investigation developed a methodology for doping high-resistivity vinyl-ester (VE) resins with an organic dopant. The polymeric resin system investigated was a Dow Derakane 411-C50 VE resin. A number of potential dopants were studied, and two in particular, tetrabutylammoniu...

413

21 CFR 177.1900 - Urea-formaldehyde resins in molded articles.  

Code of Federal Regulations, 2012 CFR

...Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins...food-contact surface of molded articles intended for use in contact...2 moles of formaldehyde in water solution. (b) The resins...The finished food-contact article, when extracted...

2012-04-01

414

21 CFR 177.1900 - Urea-formaldehyde resins in molded articles.  

Code of Federal Regulations, 2013 CFR

...Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins...food-contact surface of molded articles intended for use in contact...2 moles of formaldehyde in water solution. (b) The resins...The finished food-contact article, when extracted...

2013-04-01

415

21 CFR 177.1900 - Urea-formaldehyde resins in molded articles.  

...Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins...food-contact surface of molded articles intended for use in contact...2 moles of formaldehyde in water solution. (b) The resins...The finished food-contact article, when extracted...

2014-04-01

416

21 CFR 177.1900 - Urea-formaldehyde resins in molded articles.  

Code of Federal Regulations, 2011 CFR

...Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins...food-contact surface of molded articles intended for use in contact...2 moles of formaldehyde in water solution. (b) The resins...The finished food-contact article, when extracted...

2011-04-01

417

Self-assembly of resins and asphaltenes facilitates asphaltene dissolution by an organic acid  

E-print Network

on asphaltenes, including the effect of petroleum fluid composition. For instance, resins, naturally amphiphilic investigations into low-dosage asphaltene inhibitors used a selection of amphiphilic molecules with known structure in an effort to mimic resins, naturally-occuring petroleum amphiphiles [1]. Resins

Firoozabadi, Abbas

418

Modification of epoxy resin: a comparison of different types of elastomer  

Microsoft Academic Search

Composites were prepared using epoxy resin (ER), carboxyl-terminated butadiene acrylonitrile copolymer (CTBN) and hydroxyl-terminated polybutadiene (HTPB), in different proportions. A chemical link between the HTPB and the epoxy resin was promoted employing tolylene diisocyanate (TDI). The reactions between elastomers and epoxy resin were followed by FTIR. The mechanical properties of the composites were evaluated and the microstructure was investigated through

Valéria D. Ramos; Helson M. da Costa; Vera L. P. Soares; Regina S. V. Nascimento

2005-01-01

419

Hot-melt adhesive properties of EVA\\/aromatic hydrocarbon resin blend  

Microsoft Academic Search

A series of ethylene vinyl acetate copolymers (EVAs) were blended with aromatic hydrocarbon resins for use as hot-melt adhesives. The glass transition temperature, viscoelastic properties, melt viscosity, crystallinity and adhesion properties of the EVA\\/aromatic hydrocarbon resin system were determined as a function of the softening point of the aromatic hydrocarbon resin, the blend ratio of the two components and the

Young-Jun Park; Hyun-Joong Kim

2003-01-01

420

In vivo Degradation of Resin-Dentin Bonds in Humans Over 1 to 3 Years  

Microsoft Academic Search

The longevity of resin restorations is currently an area of great interest in adhesive dentistry. However, no work has been conducted to investigate the durability of resin-dentin bond structures using human substrate in vivo. The purpose of this study was to investigate the degradation of the resin-dentin bond structures aged in an oral environment for 1, 2, or 3 years.

M. Hashimoto; H. Ohno; M. Kaga; K. Endo; H. Sano; H. Oguchi

2000-01-01

421

Permanganate Degradation of Reillex HPQ Ion Exchange Resin for Use in HB-Line  

SciTech Connect

This study evaluated the use of Reillex TM HPQ resin as a replacement for the Ionac A-641 resin currently authorized for use in H B-Line. The study concentrated on the ability of the existing alkaline permanganate digestion process to convert spent resin for disposal.

Walker, B.W.

1999-06-02

422

Comparison of ion exchange resins used in reduction of boron in desalinated water for human consumption  

Microsoft Academic Search

There are currently different resins on the market used for the elimination of boron in water. They are composed of the same active group. These are crosslinked macroporous polystyrene resins, with the active group N-methyl-D-glucamine (NMG). The NMG of the resin captures the boron via a covalent bond. The borate ion is complexed by two sorbitol groups. A comparative study

María Fernanda Chillón Arias; Laureano Valero i Bru; Daniel Prats Rico; Pedro Varó Galvañ

2011-01-01

423

21 CFR 520.1242g - Levamisole resinate and famphur paste.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Levamisole resinate and famphur paste. 520...FORM NEW ANIMAL DRUGS § 520.1242g Levamisole resinate and famphur paste. (a...is a paste containing 11.6 percent levamisole resinate (50 percent potency)...

2010-04-01

424

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

E-print Network

conditions within a high-permeability resin-distribution medium based vacuum-assisted resin transfer molding the infiltration of a rectangular carbon fiber based preform with the NBV-800 epoxy resin and to optimize the VARTM infiltration time relative to the room-temperature infiltration time. This infiltration time reduction

Grujicic, Mica

425

NON-POLLUTING COMPOSITES REPAIR AND REMANUFACTURING FOR MILITARY APPLICATIONS: CO-INJECTION RESIN TRANSFER MOLDING  

EPA Science Inventory

Vacuum-assisted resin transfer molding (VARTM) processes have been proven to be cost-effective manufacturing techniques for large composite structures. However, their use has been limited to single resin systems. A large variety of composite structures requires multiple resins to...

426

Metabolomics Reveals the Origins of Antimicrobial Plant Resins Collected by Honey Bees  

E-print Network

Metabolomics Reveals the Origins of Antimicrobial Plant Resins Collected by Honey Bees Michael B of antimicrobial plant resins in honey bee, Apis mellifera, nests has important physiological benefits. Resin varied in inhibition of the bee bacterial pathogen, Paenibacillus larvae. We conclude that honey bees

Weiblen, George D

427

Effects of petroleum resins on asphaltene aggregation and water-in-oil emulsion formation  

E-print Network

Effects of petroleum resins on asphaltene aggregation and water-in-oil emulsion formation P in mixtures of heptane and toluene. Solubility profiles generated in the presence of resins (1:1 mass ratio without resins. Small-angle neutron scattering (SANS) was performed on solutions of asphaltene fractions

Kilpatrick, Peter K.

428

Preparative Subfractionation of Petroleum Resins and Asphaltenes. I. Development of Size Exclusion Separation Methodology  

Microsoft Academic Search

A preparative chromatographic separation methodology for petroleum resins and asphaltenes was developed. Size exclusion was the chosen separation mechanism, carried out with commercial polymeric columns. Several parameters were optimized in order to achieve repeatable and quantitative separations. Asphaltenes and resins isolated from stable and unstable crude oils were studied. Differences in the relative fraction distribution were observed for resins separated

Lante Carbognani

2003-01-01

429

Textile impregnation with thermoplastic resin - models and application  

Microsoft Academic Search

One of the key issues of the development of cost-effective thermoplastic composites for the aerospace industry is the process quality control. A complete, void free impregnation of the textile reinforcement by the thermoplastic resin is an important measure of the quality of composites. The introduction of new, more thermal resistant and tougher polymers is accompanied by a large number of

R. Loendersloot; W. J. B. Grouve; E. A. D. Lamers; S. Wijskamp; P. A. Kelly; S. Bickerton; P. Lescher; Q. Govignon

2012-01-01

430

Dual resin bonded joints in polyetheretherketone (PEEK) matrix composites  

Microsoft Academic Search

The paper describes applications of the dual resin (miscible polymer) bonding technique (Smiley, 1989) developed as an alternative to traditional bonding approaches to joining thermoplastic matrix composite subassemblies into structures. In the experiments, the performance of joint geometries, such as those that could be used to assemble large truss structures in space, are investigated using truss joint models consisting of

Steve Zelenak; Donald W. Radford; Michael W. Dean

1993-01-01

431

Carbon fibers from electrospun polymeric phenolic resin precursors  

NASA Astrophysics Data System (ADS)

This dissertation presents a technique for producing carbon fibers of nano- to micro-sized dimension by utilizing a non-conventional fiber spinning approach with refractory polymers, followed by post-processing steps, to create new carbon materials with distinctive chemical/physical property characteristics. Phenolic resins, novolak and resole, are selected for this study because of their low cost, marketability, environmental friendliness, and high char yield upon pyrolysis. The new carbon fibers are at least an order of magnitude smaller than their conventionally processed counterpart, and possess significant advantages. Phenolic resin fibers, consisting of a blend of novolak and resole, are generated via electrospinning and are subsequently cured and pyrolyzed at temperatures from 800°C to 2000°C to form carbon fibers having diameters of ˜1 mum. Fiber analysis by scanning electron microscopy confirms that the morphology generated during the electrospinning processing is retained throughout the curing and carbonization processes. X-ray diffraction suggests the presence of highly graphitized carbon, which is further validated by high-resolution transmission electron microscopy (HRTEM) analysis. There is evidence of crystalline graphite, which may have nucleated on aligned sheets presence on the fiber surface. The physical characteristics of electrospun fibers are contrary to those exhibited by pyrolyzed phenolic resins, which fall into the classification of non-graphitizing. It is likely that the thin electrospun fibers offer a template that encourages ordering not usually seen in thicker fibers or bulk samples of carbonized phenolic resins.

Gee, Diane L.

432

Epoxy resin monomers with reduced skin sensitizing potency.  

PubMed

Epoxy resin monomers (ERMs), especially diglycidyl ethers of bisphenol A and F (DGEBA and DGEBF), are extensively used as building blocks for thermosetting polymers. However, they are known to commonly cause skin allergy. This research describes a number of alternative ERMs, designed with the aim of reducing the skin sensitizing potency while maintaining the ability to form thermosetting polymers. The compounds were designed, synthesized, and assessed for sensitizing potency using the in vivo murine local lymph node assay (LLNA). All six epoxy resin monomers had decreased sensitizing potencies compared to those of DGEBA and DGEBF. With respect to the LLNA EC3 value, the best of the alternative monomers had a value approximately 2.5 times higher than those of DGEBA and DGEBF. The diepoxides were reacted with triethylenetetramine, and the polymers formed were tested for technical applicability using thermogravimetric analysis and differential scanning calorimetry. Four out of the six alternative ERMs gave polymers with a thermal stability comparable to that obtained with DGEBA and DGEBF. The use of improved epoxy resin monomers with less skin sensitizing effects is a direct way to tackle the problem of contact allergy to epoxy resin systems, particularly in occupational settings, resulting in a reduction in the incidence of allergic contact dermatitis. PMID:24830866

O'Boyle, Niamh M; Niklasson, Ida B; Tehrani-Bagha, Ali R; Delaine, Tamara; Holmberg, Krister; Luthman, Kristina; Karlberg, Ann-Therese

2014-06-16

433

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2011 CFR

...resins have a drop-softening point of 125° to 165 °C and a maximum absorptivity of 0.17 liter per gram centimeter at 266 nanometers, as determined by methods titled “Determination of Softening Point (Drop Method)” and “Determination of...

2011-04-01

434

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

...resins have a drop-softening point of 125° to 165 °C and a maximum absorptivity of 0.17 liter per gram centimeter at 266 nanometers, as determined by methods titled “Determination of Softening Point (Drop Method)” and “Determination of...

2014-04-01

435

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2012 CFR

...resins have a drop-softening point of 125° to 165 °C and a maximum absorptivity of 0.17 liter per gram centimeter at 266 nanometers, as determined by methods titled “Determination of Softening Point (Drop Method)” and “Determination of...

2012-04-01

436

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2013 CFR

...resins have a drop-softening point of 125° to 165 °C and a maximum absorptivity of 0.17 liter per gram centimeter at 266 nanometers, as determined by methods titled “Determination of Softening Point (Drop Method)” and “Determination of...

2013-04-01

437

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2010 CFR

...resins have a drop-softening point of 125° to 165 °C and a maximum absorptivity of 0.17 liter per gram centimeter at 266 nanometers, as determined by methods titled “Determination of Softening Point (Drop Method)” and “Determination of...

2010-04-01

438

Studies on Hydroxyl Terminated Polybutadiene Toughened Phenolic Resin  

Microsoft Academic Search

Phenolic novolac was modified with hydroxyl terminated polybutadiene (HTPB) using resole as compatibilizer. These systems were characterized by differential scanning calorimetry, and IR analysis. Neat resin castings were prepared with varying percentages of HTPB. The fracture toughness of these systems was assessed by evaluating the critical stress intensity factor (KIc) using single-edge notch, three-point bend specimens. The fracture behavior was

C. Nirmal; S. N. Maithi; T. Padmavathi; A. Vanaja; R. M. V. G. K. Rao

2006-01-01

439

High Temperature VARTM of Phenylethynyl Terminated Imides (PETI) Resins  

NASA Technical Reports Server (NTRS)

Fabrication of composite structures using vacuum assisted resin transfer molding (VARTM) is generally more affordable than conventional autoclave techniques. Recent efforts have focused on adapting VARTM for the fabrication of high temperature composites. Due to their low melt viscosity and long melt stability, certain phenylethynyl terminated imides (PETI) can be processed into composites using high temperature VARTM (HT-VARTM). However, one of the disadvantages of the current HT-VARTM resin systems has been the high porosity of the resultant composites. For aerospace applications a void fraction of less than 2% is desired. In the current study, two PETI resins, LARCTM PETI-330 and LARCTM PETI-8 have been used to fabricate test specimens using HT-VARTM. The resins were infused into carbon fiber preforms at 260 C and cured between 316 C and 371 C. Modifications to the thermal cycle used in the laminate fabrication have reduced the void content significantly (typically < 3%) for carbon fiber biaxially woven fabric. Photomicrographs of the panels were taken and void contents were determined by acid digestion. For carbon fiber uniaxial fabric, void contents of less than 2% have been obtained using both PETI-8 and PETI-330. Mechanical properties of the panels were determined at both room and elevated temperatures. These include short beam shear and flexure tests. The results of this work are presented herein.

Ghose, Sayata; Cano, Roberto J.; Britton, Sean M.; Watson, Kent A.; Jensen, Brian J.; Connell, John W.

2010-01-01

440

Analysis of polystyrene and related resins by pyrolysis gas chromatography  

Microsoft Academic Search

Pyrolysis gas chromatography was used for the determination of the monomeric composition of some hydrocarbon resins resulting from the liquid product of naphtha pyrolysis. The effect of working conditions on the peak composition of the pyrogram was investigated. From the monomer peak areas corrected by experimental factors the monomeric composition of a copolymer can be calculated.

P. Fuchs; C. Szepesy

1968-01-01

441

Opportunities for Energy Efficiency in Hydrocarbon Resin Manufacturing Facilities  

Microsoft Academic Search

Detailed plant-wide assessment of two hydrocarbon resin manufacturing facilities of Neville Chemical revealed significant opportunities for energy efficiency, and consequently air emissions and green house gas reduction in such facilities. The energy efficiency opportunities (EEOs) in the Anaheim plant, the smaller of the two facilities, could save 27% of the facility's annual electrical energy usage, and 36% of its annual

Ahmad R. Ganji; Bryan Hackett; Sandra Chow; Robert Lonergan; John Wimer

442

Bacterial adhesion to hydrocarbons: Role of asphaltenes and resins  

Microsoft Academic Search

The influence of asphaltenes and resins on bacterial adhesion to model crude oils was examined using a modified microbial adhesion to hydrocarbons assay. Well-controlled bacterial adhesion experiments were conducted at three solution pHs (4, 6 and 7) using Pseudomonas aeruginosa and Pseudomonas putida and four model crude oil systems containing up to four representative hydrocarbon compounds found in crude oils.

Caroline Warne Zoueki; Subhasis Ghoshal; Nathalie Tufenkji

2010-01-01

443

Artificial weathering of wood surfaces modified by melamine formaldehyde resins  

Microsoft Academic Search

Spruce and poplar samples were treated with different melamine formaldehyde resins. A long term artificial weathering experiment was performed in order to clarify the resistance to weathering regarding wood colour and surface hardness. The increase in hardness due to melamine treatment was well preserved after simulated long term weathering. The treated samples also showed advantages compared to untreated reference samples

Christian Hansmann; Manabendra Deka; Rupert Wimmer; Wolfgang Gindl

2006-01-01

444

Solubility of Two Resin Composites in Different Mouthrinses  

PubMed Central

Aim. This study aimed to compare the solubility of a universal restorative resin composite (Filtek Z250; FZ250) and a silorane-based resin composite (Filtek Silorane; FS) after immersion in alcohol-containing mouthrinse, alcohol-free mouthrinse, and artificial saliva. Methods. 30 discs (10?mm?×?1?mm) were prepared from each material and desiccated until a constant mass was obtained. Specimens were immersed in the test solutions for two days and desiccated again. Solubility was calculated based on the change in weight of each specimen before and after immersion. Data was analyzed using two-way ANOVA and Tukey's Post Hoc test (P < 0.05). Results. Solubility values for both resin composites were the highest in the alcohol-containing mouthrinse. FZ250 showed greater solubility than FS; the difference was only significant in artificial saliva. Conclusion. Both resin-composite materials tested exhibited some degree of solubility in each of the test solutions. The use of an alcohol-free mouthrinse may be preferable for patients with extensive composite restorations. PMID:24809053

Ozer, Sezin; Sen Tunc, Emine; Tuloglu, Nuray; Bayrak, Sule

2014-01-01

445

Progress in Solidification of Radioactive Waste Resins Using Specific Cement  

SciTech Connect

A kind of special cement (Named as ASC) was used in radioactive spent resins solidification in China. A prescription of X ASC cement + 0.5 X waste resins (50% water hold) + 0.35 X water was obtained first. In order to control the temperature rise caused by hydration of cement in 200 L solidification matrix, various supplementary materials were tried. Based on compressive strength tests and center temperature rise, super powered zeolite was selected. In addition, more resins were added to reduce the center temperature rise. A superior combination was obtained as ASC 35 wt.%, zeolite 7 wt.% to mix 42 wt.% of resins (50% water hold) with 16 wt.% of water. The microstructures of hydrated OPC, ASC and ASC with different zeolite addition were compared by means of Scanning Electron Microscopy (SEM). From the SEM pictures, the structures of the needles or spines can be seen in ASC matrices and the needles structure of ASC change into flake structure gradually with more zeolite added. The simulated leaching tests showed that inclusion of zeolite in ASC reduced the leaching rates of radionuclides significantly. From 200 L matrix test, the centre temperature curve was measured, and the highest temperature was lower than 90 deg. C. No thermal cracks were found in the final solidified products. (authors)

Li, J.F.; Ye, Y.C.; Wang, J.L. [Institute of Nuclear and New Energy Technology - INET, Tsinghua University, Beijing 100084 (China)

2006-07-01

446

Permeability reduction by asphaltenes and resins deposition in porous media  

Microsoft Academic Search

The deposition of crude oil polar fractions such as asphaltenes and resins in oil reservoir rocks reduce considerably the rock permeability and the oil production. In the present work, a crude oil and various core samples were extracted from Rhourd–Nouss (RN) reservoir rock. Afterwards, core flow experiments were carried out in the laboratory to investigate permeability reduction that causes formation

R. Hamadou; M. Khodja; M. Kartout; A. Jada

2008-01-01

447

Alternating electric field induced agglomeration of carbon black filled resins  

Microsoft Academic Search

This letter reports on our observation that an alternating electric field is able to induce the formation of an electrically conducting network in carbon black (CB) filled resins well below the zero-field percolation threshold. Compared with the recently presented dc method, the ac agglomeration is more efficient in two respects: it proceeds significantly faster under equivalent conditions and is still

Matthias-Klaus Schwarz; Wolfgang Bauhofer; Karl Schulte

2002-01-01

448

Energy Conservation Opportunities in Hydrocarbon Resin Manufacturing Facilities  

E-print Network

"The results of a plant-wide assessment of the manufacturing facilities of Neville Chemical Company, a manufacturer of hydrocarbon resins will be presented in this paper. The project was co-funded by US Department of Energy under its Plant...

Ganji, A. R.; Hackett, B.; Chow, S.; Lonergan, R.; Wimer, J.

449

Preventing fouling of ion-exchange resins - II  

SciTech Connect

Reports on agents that can reduce the efficiency of ion-exchange resins, together with some simple field tests used to confirm fouling. The problem of fouling by oily or greasy materials is encountered almost exclusively in cation resins. Treatment with a nonionic surfactant-based alkaline cleaner is the most effective approach to the removal of oily and greasy foulants. Cation resins can be treated in an offline cleanup or by maintenance feed to the backwash water. The major problem associated with silt or clay fouling is the impedance to water flow caused, and the resulting channeling of impurities through the bed. Surfactant/alkaline cleaners are highly effective in removing silt and clay from the bed. Other topics covered include colloidal silica fouling, testing for ''organic'' fouling, and a field test to confirm iron fouling. Concludes that the increased use of ion-exchange equipment and boiler-water treatment programs formulated for use with ''pretreated'' water has heightened the need for ionexchangers to operate as effectively as possible. Fouling of ionexchange resin by metal oxides, salts, oil, silt, silica and various organic compounds can result in a reduction of exchange efficiency. Proper selection of cleaning programs can restore much of this lost efficiency. The implementation of chemical maintenance programs can often avert the recurrence of fouling and assure good water quality.

Pelosi, P.; McCarthy, J.

1982-09-01

450

Chemoviscosity modeling for thermosetting resin systems, part 3  

NASA Technical Reports Server (NTRS)

A new analytical model for simulating chemoviscosity resin has been formulated. The model is developed by modifying the well established Williams-Landel-Ferry (WLF) theory in polymer rheology for thermoplastic materials. By introducing a relationship between the glass transition temperature (T sub g (t)) and the degree of cure alpha(t) 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 parameters C sub 1 (T) and C sub 2 (T) were determined from the isothermal cure data. Theoretical predictions of the model for the resin under dynamic heating cure cycles were shown to compare favorably with the experimental data. This work represents a progress toward establishing 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.

Hou, T. H.; Bai, J. M.

1988-01-01

451

Composite micromechanics of hemp fibres and epoxy resin microdroplets  

Microsoft Academic Search

It is shown that the microdeformation of single hemp fibres can be monitored by following the peak shift of the 1095 cm?1 Raman band with respect to strain and stress. This relationship is then used to monitor the deformation micromechanics of strained single hemp fibres with a microdroplet of epoxy resin attached along the gauge length. It is shown that

S. J. Eichhorn; R. J. Young

2004-01-01

452

Scratch resistance of different silica filled resins for obturation materials  

E-print Network

as several com- mercial obturation resins in tests of scratch resistance. Hardness and size of the inorganic nanoparticles providing the materials with improved mechanical properties. Scratch testing results show low of rigidity from hard to soft elastomers, and ease of fabrication in different forms. On the other hand

North Texas, University of

453

Ion Exchange Resin for Assessing Phosphorus Availability in Soils  

Microsoft Academic Search

hosphorus has received considerable attention in the research of methods of soil analysis, but agreement on best methodology is lacking. Resin extractable P seems to be a superior method, but its adoption in routine soil testing is still limited worldwide. When there is a choice between several methods of analy- sis, if results are not comparable, greenhouse experiments under controlled

Bernardo van Raij; H. Cantarella; J. A. Quaggio; Luís Ignácio Prochnow

454

Biobased composites from glyoxal-phenolic resins and sisal fibers.  

PubMed

Lignocellulosic materials can significantly contribute to the development of biobased composites. In this work, glyoxal-phenolic resins for composites were prepared using glyoxal, which is a dialdehyde obtained from several natural resources. The resins were characterized by (1)H, (13)C, 2D, and (31)P NMR spectroscopies. Resorcinol (10%) was used as an accelerator for curing the glyoxal-phenol resins in order to obtain the thermosets. The impact-strength measurement showed that regardless of the cure cycle used, the reinforcement of thermosets by 30% (w/w) sisal fibers improved the impact strength by one order of magnitude. Curing with cycle 1 (150 degrees C) induced a high diffusion coefficient for water absorption in composites, due to less interaction between the sisal fibers and water. The composites cured with cycle 2 (180 degrees C) had less glyoxal resin coverage of the cellulosic fibers, as observed by images of the fractured interface observed by SEM. This study shows that biobased composites with good properties can be prepared using a high proportion of materials obtained from natural resources. PMID:19880315

Ramires, Elaine C; Megiatto, Jackson D; Gardrat, Christian; Castellan, Alain; Frollini, Elisabete

2010-03-01

455

Thermocycling Effects on Resin Bond to Silicatized and Silanized Zirconia  

Microsoft Academic Search

Various techniques have been introduced to create a durable resin composite bond to sintered zirconia (Y-TZP). Shear bond strength values achieved through tribochemical treatment have been investigated in numerous studies, but less is reported about long-term durability. The objective here was to evaluate the effects of thermocycling and silane on shear bond strength of a composite luting cement to silicatized

Timo T. Heikkinen; Lippo V. J. Lassila; Jukka P. Matinlinna; Pekka K. Vallittu

2009-01-01

456

Modification of polyester resins with active mineral fillers  

Microsoft Academic Search

The technological and operational properties of polyester resins, unmodified and modified with new freely disperse fillers, were investigated. It was found that modification causes greater dependence of the viscosity on the fatigue load and acceleration of the curing reaction and an increase in the exothermic effect by 2.5-4.5 times. In addition, the strength properties of the modified composites and the

A. V. Murafa; N. I. Bobyreva; V. G. Khozin

1996-01-01

457

Optical X-ray density of composite resin luting agents.  

PubMed

This study verified the optical density of four composite resin luting agents - RelyX ARC (RY), Enforce (E), C&B Cement (CB) and Flow it (FI), at thicknesses of 2, 3, and 4 mm. The optical density of the luting agents was compared with that of enamel and dentin at the same thicknesses. Fifteen tooth crowns were embedded in PVC cylinders with self-cured acrylic resin. In addition, acrylic resin was poured into 5 PVC cylinders and four equidistant 5 mm diameter holes were prepared, with one luting material inserted in each. A laboratory cutting machine was used to prepare 4-, 3- and 2-mm thick slices of the tooth crowns and materials. Digital images were obtained with a Digora system. Three radiographs of each thickness were obtained, totalizing 135 radiographs of the crowns and 45 of the materials. Three readings were carried out on each radiograph: three in enamel, three in dentin and three in each material, totalizing 1350. According to Students t-test (presin luting agents E and FI can be distinguished from dental structures, while the CB and RY are not easily distinguished. PMID:22165313

Carracho, Helena G; da Silveira, Ivori D; Soares, Clarissa G; Paranhos, Maria Paula G; Júnior, Luiz Henrique Burnett; Spohr, Ana Maria

2011-01-01

458

Experimental and modeling studies of clay\\/polydicyclopentadiene resin nanocomposites  

Microsoft Academic Search

Hybrid organic-inorganic nanocomposites have received considerable attention during the last five years due to their unexpected properties. This work incorporated nanodispersed organically modified montmorillonite clay into polydicyclopentadiene resin matrices. Montmorillonite consists of 1 nm platelet sheets with a 2:1 structure, consisting of an alumina octahedral layer sandwiched between two silica tetrahedral layers. The relative weak forces between platelets allow small

Mitra Yoonessi

2004-01-01

459

Compatibility of resin-coated proppants with crosslinked fracturing fluids  

SciTech Connect

This paper describes the additive interaction and/or compatibility of various resin-coated proppants (RCP's) with low-, neutral-, and high-pH water-based fracturing fluids. Solutions are provided for those fluids exhibiting compatibility problems with RCP's.

Nimerick, K.H.; McConnell, S.B.; Samuelson, M.L. (Dowell Schlumberger (US))

1992-02-01

460

Resin flow through fiber reinforcements during composite processing  

SciTech Connect

In composite processes such as resin transfer molding, pultrusion, autoclave molding, and compression molding, understanding resin flow through reinforcing materials is extremely important. The work described in this paper is part of a larger effort designed to model resin flow inside an injection-pultrusion die. As part of this study, and experimental fixture for measuring in-plane permeability as a function of fiber volume fraction for fiber materials was developed. This paper will present the results of an experimental and analytical investigation of in-plane flow through fiber reinforcements. Experimental results show that permeability is very dependent on fiber orientation. At low fiber volume fraction (V{sub f} < 0.45), in-plane permeability seems to increase with an increasing number of 0/90 cloth layers. Permeability is also dependent on flow rate and resin saturation in the fiber sample. An empirical permeability model was developed based on the compression study. This paper also discusses the flow behavior of combined layers can be predicted based on single material permeability and compressibility data.

Young Roak Kim; McCarthy, S.P. (Univ. of Lowell, MA (United States)); Fanucci, J.P.; Nolet, S.C.; Koppernaes, C. (Amican Composite Technology Inc., Boston, MA (United States))

1991-04-01

461

Miscibility Between Ethylene Vinyl Acetate Copolymers and Tackifier Resins  

Microsoft Academic Search

A series of ethylene vinyl acetate copolymer (EVA) were blended with various kinds of tackifiers and the miscibility between the components was investigated. The miscibility of the blend is illustrated as a phase diagram. The EVA and modified rosin systems tended to have a phase diagram with lower critical solution temperature (LCST), whereas the EVA and petroleum resin systems tended

Mototsugu Takemoto; Takuma Karasawa; Hiroshi Mizumachi; Mikio Kajiyama

2000-01-01

462

Management of Spent Organic Ion-Exchange Resins by Photochemical Oxidation  

SciTech Connect

Management of spent ion-exchange resin waste arising from nuclear reactor operations by traditional practice of encapsulation in cement is associated with problems such as swelling and disintegration. Complete oxidation (mineralization) is an attractive alternative option. This paper reports the development of photochemical mineralization process for organic ion-exchange resins of poly (styrene-divinyl benzene) type with sulfonic acid and quaternary ammonium functional groups. It is a two-step process consisting of dissolution (conversion of solid resin into water-soluble reaction products) and photo-Fenton mineralization of the dissolved resin. Cation and anion resin dissolution was effected by reaction of the resin with H2O2 at 50-60 C in the presence of ferrous/copper sulphate catalyst. Direct dissolution of mixed resin was not efficient. However, the cation resin portion in the mixed resin could be selectively dissolved without affecting the anion portion. The solid anion resin after separation from the cation resin solution could be dissolved. About 0.5 liters of 50% H2O2 was required for dissolution of one kg of wet resin. The reaction time was 4-5 hours. Dissolution experiments were conducted on up to 8 liters of wet resin. The second step, viz., photo-Fenton mineralization of the dissolved resin was effected at ambient temperature(25-35 C). Kinetic results of laboratory scale experiments in immersion type photo-reactor and pilot scale experiments in tubular flow photo-reactor were presented. These results clearly demonstrated the photo-Fenton mineralization of dissolved resin at ambient temperature with stoichiometric quantity of H2O2 as against 70-200% excess H2O2 requirement in chemical mineralization experiments under Fenton oxidation conditions at 90-95 C. Based on these studies, a treatment scheme was developed and presented in this paper.

Srinivas, C.; Sugilal, S.; Wattal, P. K.

2003-02-26

463

Cesium Ion Exchange Loading Kinetics Testing with SRF Resin  

SciTech Connect

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 loading may include a broader range of sodium molarities (2 to 8 M) due to caustic leaching and higher temperatures (50°C) to alleviate post-filtration precipitation issues prior to reaching the ion exchange columns. 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 linear load velocity (4, 6, 8 cm/min), initial sodium concentration (2, 5, 8 M), initial sodium-to-cesium ratio (1.4E+05, 2.1E+05, 2.8E+05 mol/mol), initial sodium-to-hydroxide ratio (2.0, 3.0, 4.0 mol/mol), and resin degradation during extended solution flow using elevated temperature (45°, 50°, 55°, 60°, 65°, 75°C). Testing was performed using a~2mL column packed with SRF resin with feed flowing through it in an up-flow pattern. Samples were taken at set intervals and the data analyzed to help understand the impact of these conditions on the SRF resin performance. It was found that the loading kinetics were not significantly impacted by the sodium concentration over the range tested. However, the loading kinetics were impacted by the linear load velocity. These results indicated that at the test temperature, the adsorption of cesium is strongly dependent on mass transfer through the film and not significantly impacted by interparticle diffusion. 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.

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

2012-11-02

464

PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN  

SciTech Connect

Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Seven of the cycles were completed in the 12-inch IX Column and sixteen cycles were completed in the 24-inch IX Column. Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 2 1/2 times better than the design requirements of the WTP full-scale system. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. In downflow of the Regeneration and Simulant Introduction steps, the resin bed particles pack tightly together and produce higher hydraulic pressures than that found in upflow. Also, upflow Simulant Introduction produced an ideal level bed for the twenty cycles completed using upflow Simulant Introduction. Conversely, the three cycles conducted using downflow Simulant Introduction produced an uneven bed surface with erosion around the thermowells. The RF resin bed in both columns showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. Micrographs comparing representative bead samples before and after testing indicated no change in bead morphology. The skeletal density of the RF resin in the 24-inch IX Column increased slightly with cycling (in both hydrogen and sodium form). The chemical solutions used in the pilot-scale testing remained clear throughout testing, indicating very little chemical breakdown of the RF resin beads. The RF resin particles did not break down and produce fines, which would have resulted in higher pressure drops across the resin bed. Three cesium (Cs) loading tests were conducted on the RF resin in pilot-scale IX columns. Laboratory analyses concluded the Cs in the effluent never exceeded the detection limit. Therefore, there was no measurable degradation in cesium removal performance. Using the pilot-scale systems to add the RF resin to the columns and removing the resin from the columns was found to work well. The resin was added and removed from the columns three times with no operational concerns. Whether the resin was in sodium or hydrogen form, the resin flowed well and resulted in an ideal resin bed formation during each Resin Addition. During Resin Removal, 99+ % of the resin was easily sluiced out of the IX column. The hydraulic performance of the spherical RF resin during cycle testing was found to be superior to all other tested IX resins, and SRNL testing indicates that the resin should hold up to many cycles in actual radioactive Cs separation. The RF resin was found to be durable in the long term cycle testing and should result in a cost saving in actual operations when compared to other IX resins.

Adamson, D

2007-01-09

465

PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN  

SciTech Connect

Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project-Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Seven of the cycles were completed in the 12 inch IX Column and sixteen cycles were completed in the 24 inch IX Column. Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 2 1/2 times better than the design requirements of the WTP full-scale system. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. In downflow of the Regeneration and Simulant Introduction steps, the resin bed particles pack tightly together and produce higher hydraulic pressures than that found in upflow. Also, upflow Simulant Introduction produced an ideal level bed for the twenty cycles completed using upflow Simulant Introduction. Conversely, the three cycles conducted using downflow Simulant Introduction produced an uneven bed surface with erosion around the thermowells. The RF resin bed in both columns showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. Micrographs comparing representative bead samples before and after testing indicated no change in bead morphology. The skeletal density of the RF resin in the 24 inch IX Column increased slightly with cycling (in both hydrogen and sodium form). The chemical solutions used in the pilot-scale testing remained clear throughout testing, indicating very little chemical breakdown of the RF resin beads. The RF resin particles did not break down and produce fines, which would have resulted in higher pressure drops across the resin bed. Three cesium (Cs) loading tests were conducted on the RF resin in pilot-scale IX columns. Laboratory analyses concluded the Cs in the effluent never exceeded the detection limit. Therefore, there was no measurable degradation in cesium removal performance. Using the pilot-scale systems to add the RF resin to the columns and removing the resin from the columns was found to work well. The resin was added and removed from the columns three times with no operational concerns. Whether the resin was in sodium or hydrogen form, the resin flowed well and resulted in an ideal resin bed formation during each Resin Addition. During Resin Removal, 99+ % of the resin was easily sluiced out of the IX column. The hydraulic performance of the spherical RF resin during cycle testing was found to be superior to all other tested IX resins, and SRNL testing indicates that the resin should hold up to many cycles in actual radioactive Cs separation. The RF resin was found to be durable in the long term cycle testing and should result in a cost saving in actual operations when compared to other IX resins.

Adamson, D

2006-11-08

466

Comparison of XAD macroporous resins for the concentration of fulvic acid from aqueous solution  

USGS Publications Warehouse

Five macroreticular, nonlonlc AmberlHe XAD resins were evaluated for concentration and Isolation of fulvlc acid from aqueous solution. The capacity of each resin for fulvlc acid was measured by both batch and column techniques. Elution efficiencies were determined by desorptlon with 0.1 N NaOH. Highest recoveries were obtained with the acrylic ester resins which proved to be most efficient for both adsorption and elution of fulvlc acid. Compared to the acrylic ester resins, usefulness of the styrene dvlnybenzene resins to remove fulvlc acid is limited because of slow diffusion-controlled adsorption and formation of charge-transfer complexes, which hinders elution. ?? 1979 American Chemical Society.

Aiken, G.R.

1979-01-01

467

Reillex/trademark/ HPQ: A new, macroporous polyvinylpyridine resin for separating plutonium using nitrate anion exchange  

SciTech Connect

Anion exchange in nitric acid is the major aqueous process used to recover and purify plutonium from impure scrap materials. Most strong-base anion exchange resins incorporate a styrene-divinylbenzene copolymer. A newly available, macroporous anion exchange resin based on a copolymer of 1-methyl-4-vinylpyridine and divinylbenzene has been evaluated. Comparative data for Pu(IV) sorption kinetics and capacity are presented for this new resin and two other commonly used anion exchange resins. The new resin offers high capacity and rapid sorption kinetics for Pu(IV) from nitric acid, as well as greater stability to chemical and radiolytic degradation. 8 refs., 12 figs.

Marsh, S.F.

1989-01-01

468

Effect of cresol monomers in three-component novolak resin on photolithographic performance  

NASA Astrophysics Data System (ADS)

In our previous publication we reported an improved process for isolation of novolak resins form phenol-formaldehyde condensation mixtures. The process results in resins having low polydispersity and slow photospeed. Novolak resins were prepared by the same process, employing different ratios of the cresol components. This paper will discuss an experimental design analyzing relationship between cresol component ratios and properties of the resins. The characteristics of the resins and their effect on the lithographic performances as an i-line photoresist composition will also be discussed.

Kim, Woo-Kyu; Rahman, M. D.; Ficner, Stanley A.; Khanna, Dinesh N.

1999-06-01

469

Novolak resin for ultrafast high-resolution positive i-line photoresist compositions  

NASA Astrophysics Data System (ADS)

An improved process for isolation of novolak resins from phenol-formaldehyde condensation products has been developed. The process results in resins having low polydispersity and higher photospeed while typical phenol/formaldehyde resin syntheses generate a broad distribution of molecular weight fragments with a wide polydispersity. The novolak resins were characterized by NMR and GPC and were formulated to obtain ultra fast high resolution i-line photoresists. The characteristics of the resins and their effect on lithographic properties as i-line photoresist compositions will be discussed in this paper.

Rahman, M. D.; Lu, Ping-Hung; Cook, Michelle M.; Kim, Woo-Kyu; Khanna, Dinesh N.

1998-06-01

470

Removal of dyes from water using crosslinked aminomethane sulfonic acid based resin.  

PubMed

A new polymeric resin with amino sulfonic acid pendant functions has been prepared for the extraction of acidic and basic dyes from water. Beaded polymer supports were prepared by suspension polymerization of vinyl benzyl chloride (0.9 mol) and ethylene glycol dimethacrylate (0.1 mol). The resulting copolymer beads were modified with amino methane sulfonic acid. The dye adsorption capacity of the resin was found as 0.16 g dye/g resin for ramazol black and 0.15 g dye/g resin for crystal violet. The pH depending measurements and dye sorption kinetics of the resin were also investigated. PMID:20401517

Kaner, Damla; Saraç, Ayfer; Senkal, Bahire Filiz

2010-08-01

471

Resin Capsules: Permeable Containers for Parallel/Combinatorial Solid-Phase Organic Synthesis  

PubMed Central

A resin capsule is a permeable container for resin beads designed for multiple/combinatorial solid-phase organic synthesis. Resin capsules consist of a high density polyethylene ring sealed with peek mesh on both sides. The cylindrical shape of resin capsules enabled space-saving packing into plastic column-like reaction vessels commonly used for solid-phase organic synthesis. Resin capsules have been evaluated for their use in combinatorial synthesis, and a set of model compounds with excellent purity was prepared. PMID:18656988

Bouillon, Isabelle; Soural, Miroslav; Krchnak, Viktor

2009-01-01

472

Effect of Cigarette Smoke on Acrylic Resin Teeth  

PubMed Central

Background: The discolouration of artificial teeth, which hampers aesthetics, is one of the negative effects of cigarette smoking. Therefore, the effect of cigarette smoke on the colour stability of commercially available acrylic resin teeth needs to be evaluated for clinical success and to ascertain as to which brand has superior properties. Material and Methods: Three commercially available acrylic teeth were evaluated, after division into Group A (Premadent), Group B (Astra), and Group C (Sanyo- Dent). Selected brands were subdivided as study group and control group. Each set of acrylic resin teeth were stored in artificial saliva at 37±1°C for 24 hours. After 24 hours of immersion, the colour measurement of each tooth (T0) was performed. Second colour measurements were done after 21 days (T21) of exposure to cigarette smoke for study group and after immersion in artificial saliva for control group. All data was statistically analyzed by using Repeated Measures ANOVA and Two-way ANOVA (p<0.05). Results: Group A showed least total colour change on exposure to cigarette smoke, followed by Group B and Group C had the highest total colour change. In control group, after immersion in artificial saliva, a slight increase in total colour change was observed for all groups, which was clinically acceptable. Conclusion: Group A (crosslinked acrylic resin teeth) was more colour stable and more resistant to the discolouration which was caused by cigarette smoke, followed by Group B (crosslinked acrylic resin teeth). Group C (Non-crosslinked acrylic resin teeth) was least colour stable and most susceptible to discolouration which was caused by cigarette smoke. PMID:24179942

Patil, Seema S.; M.R., Dhakshaini; Gujjari, Anil Kumar

2013-01-01

473

Polymer-grafted silica: A screening system for polymeric adsorption resin development  

SciTech Connect

A screening-level methodology was developed for the evaluation of solute affinity for polymers that are candidate sorption resins. In this approach novel grafted polymer-silica resins were synthesized to produce poly(vinylpyrrolidone)-silica (PVP-Si) and poly(vinyl acetate)-silica (PVAc-Si) resins. The polymer-silica resins along with a number of commercially available polymer resins were used to evaluate the aqueous-phase adsorption of phenol, tetrachloroethene (PCE), trichloroethene (TCE), and chloroform. The polymer-grafted silicas were able to selectively remove pollutants from water with a covalently bonded polymer layer that has a high affinity for the target pollutant. The PVAc-silica resin had a sorption capacity for TCE and CHCl[sub 3] as high as commercial poly(styrene) resin XAD-4; the PVP-Si resin had a sorption capacity for phenol higher than a commercial poly-(vinylpyridine) resin (Reillex 425). PCE adsorption onto the PVAc-silica was comparable to the commercial poly(methacrylate) and poly(vinylpyridine) resins but less than the poly(styrene) resin. The results show that the Hildebrand solubility parameter along with the dipole moment of the polymer functional groups can be used for an initial screening-level assessment of polymer-solute affinity.

Browne, T.E.; Cohen, Y. (Univ. of California, Los Angeles (United States))

1993-04-01

474

Difference in the color stability of direct and indirect resin composites  

PubMed Central

Indirect resin composites are generally regarded to have better color stability than direct resin composites since they possess higher conversion degree Objective The present study aimed at comparing the changes in color (?E) and color coordinates (?L, ?a and ?b) of one direct (Estelite Sigma: 16 shades) and 2 indirect resin composites (BelleGlass NG: 16 shades; Sinfony: 26 shades) after thermocycling. Material and Methods Resins were packed into a mold and light cured; post-curing was performed on indirect resins. Changes in color and color coordinates of 1-mm-thick specimens were determined after 5,000 cycles of thermocycling on a spectrophotometer. Results ?E values were in the range of 0.3 to 1.2 units for direct resins, and 0.3 to 1.5 units for indirect resins, which were clinically acceptable (?E<3.3). Based on t-test, ?E values were not significantly different by the type of resins (p>0.05), while ?L, ?a and ?b values were significantly different by the type of resins (p<0.05). For indirect resins, ?E values were influenced by the brand, shade group and shade designation based on three-way ANOVA (p<0.05). Conclusion Direct and indirect resin composites showed similar color stability after 5,000 cycles of thermocycling; however, their changes in the color coordinates were different. PMID:21552717

LEE, Yong-Keun; YU, Bin; LIM, Ho-Nam; LIM, Jin Ik

2011-01-01

475

Advanced resin systems and 3D textile preforms for low cost composite structures  

NASA Technical Reports Server (NTRS)

Advanced resin systems and 3D textile preforms are being evaluated at Lockheed Aeronautical Systems Company (LASC) under NASA's Advanced Composites Technology (ACT) Program. This work is aimed towards the development of low-cost, damage-tolerant composite fuselage structures. Resin systems for resin transfer molding and powder epoxy towpreg materials are being evaluated for processability, performance and cost. Three developmental epoxy resin systems for resin transfer molding (RTM) and three resin systems for powder towpregging are being investigated. Various 3D textile preform architectures using advanced weaving and braiding processes are also being evaluated. Trials are being conducted with powdered towpreg, in 2D weaving and 3D braiding processes for their textile processability and their potential for fabrication in 'net shape' fuselage structures. The progress in advanced resin screening and textile preform development is reviewed here.

Shukla, J. G.; Bayha, T. D.

1993-01-01

476

Allergenic potential of abietic acid, colophony and pine resin-HA. Clinical and experimental studies.  

PubMed

Resin acids are considered to be the main allergens in colophony (rosin). Tall oils also contain resin acids and may then be potential sensitizers. A resin acid concentrate (pine resin-HA) together with Chinese colophony were included in our standard series and applied on 563 patients with contact dermatitis. Fourteen showed an isolated sensitivity to colophony and two to pine resin-HA. Six patients reacted to both test compounds. Guinea pig maximization tests (Magnusson & Kligman 1969) showed that pine resin-HA (2 series) was a grade I allergen, abietic acid a grade III allergen and colophony a grade IV allergen. The risk that the resin acids in tall oils would induce contact sensitivity to workers exposed to tall oil-containing products like cutting fluids and cleansing agents is considered to be minimal. PMID:7214893

Karlberg, A T; Boman, A; Wahlberg, J E

1980-12-01

477

Development of new and improved polymer matrix resin systems, phase 1  

NASA Technical Reports Server (NTRS)

Vinystilbazole (vinylstryrylpyridine) and vinylpolystyrulpyridine were prepared for the purpose of modifying bismaleimide composite resins. Cure studies of resins systems were investigated by differential scanning calorimetry. The vinylstyrylpyridine-modified bismaleimide composite resins were found to have lower cure and gel temperatures, and shorter cure times than the corresponding unmodified composite resins. The resin systems were reinforced with commercially avialable satin-weave carbon cloth. Prepregs were fabricated by solvent or hot melt techniques. Thermal stability, flammability, moisture absorption, and mechanical properties of the composites (such as flexural strength, modulus, tensile and short beam shear strength) were determined. Composite laminates showed substantial improvements in both processability and mechanical properties compared to he bismaleimide control systems. The vinylstyrylpyridine modified bismaleimide resins can be used as advanced matrix resins for graphite secondary structures where ease of processing, fireworthiness, and high temperature stability are required for aerospace applications.

Hsu, M. S.

1983-01-01

478

Effect of adhesive system on retention in posts comprising fiber post and core resin.  

PubMed

The purpose of this study was to compare the retention of fiber-reinforced composite (FRC) posts luted with either conventional or self-adhesive resin cement. The FRC posts and core resin were built up in bovine teeth. The posts were luted with standard etch-andrinse cement, self-etch cement, or one of two self-adhesive cements. The samples were stored in water for 1 or 14 days or subjected to thermal cycling (TC). Retention value was measured with the pull-out test using a universal testing machine. Conventional adhesive resin cement yielded significantly greater retention than self-adhesive resin cement at 1 day. No significant difference was observed in retention among the adhesive systems tested at 14 days or after TC. During the early luting stage, self-adhesive resin cement yielded lower retention value than conventional resin cement. After 14 days storage or TC, retention was comparable to that with conventional resin cement. PMID:23903651

Soejima, Hirotaka; Takemoto, Shinji; Hattori, Masayuki; Yoshinari, Masao; Kawada, Eiji; Oda, Yutaka

2013-01-01

479

Inkjet-printing of nonsintered alumina-resin hybrid films and their dielectric properties  

NASA Astrophysics Data System (ADS)

We used the inkjet printing method to fabricate alumina-resin hybrid films without a high temperature sintering process. The dielectric properties of the alumina-resin hybrid films were studied in order to assess if the alumina-resin hybrid films are applicable to the electronic package substrates. Various numerical models were introduced to understand the relative permittivity of the alumina-resin hybrid films. Q-values of the alumina-resin hybrid films are also measured and compared to the commercially available substrate materials. The impact of microvoids on the Q-value of the inkjet-printed alumina-resin hybrid films was also studied. The microstructures of the inkjet-printed hybrid materials were investigated in order to confirm if the microvoids in the films were filled with the resin.

Hwang, Myung-sung; Kim, Jihoon; Kim, Hyo-tae; Yoon, Youngjoon; Hyun, Sangil; Kim, Jonghee; Lee, Sung-nam; Moon, Jooho

2010-11-01

480