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1

The study of various parameters affecting the ion exchange of Cu2+, Zn2+, Ni2+, Cd2+, and Pb2+ from aqueous solution on Dowex 50W synthetic resin.  

PubMed

A gel resin containing sulfonate groups (Dowex 50W) was investigated for its sorption properties towards copper, zinc, nickel, cadmium and lead metal ions. The use of selective ion exchange to recover metals from aqueous solution has been studied. The ion exchange behavior of five metals on Dowex 50W, depending on pH, temperature, and contact time and adsorbate amount was studied. Experimental measurements have been made on the batch sorption of toxic metals from aqueous solutions using cation exchanger Dowex 50W. The maximum recoveries (about 97%) Cu(2+), Zn(2+), Ni(2+), Cd(2+) and (about 80%) Pb(2+) were found at pH ranges 8-9. The amount of sorbed metal ion was calculated as 4.1, 4.6, 4.7, 4.8, and 4.7mequiv./gram dry resin for Pb(2+), Cu(2+), Zn(2+), Cd(2+), and Ni(2+), respectively. The precision of the method was examined at under optimum conditions. Selectivity increased in the series: Pb>Cd>Cu>Zn>Ni. It has been observed that, selectivity of the -SO(3)H group of the resin increases with atomic number, valance, degree of ionization of the exchanged metals. The equilibrium ion exchange capacity of resin for metal ions was measured and explored by using Freundlich and Langmuir isotherms. Langmuir type sorption isotherm was suitable for equilibrium studies. PMID:16352392

Pehlivan, Erol; Altun, Turkan

2006-06-30

2

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

NASA Astrophysics Data System (ADS)

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

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

3

Cation Exchange Chromatographic Separation of Scandium from Other Elements on Dowex 50W-X8  

Microsoft Academic Search

Cation exchange chromatographic studies of scandium on Dowex 50W-X8 are reported. Mineral acids and their salts were tested as eluants. Their efficiency was evaluated in terms of the elution constant and the bed distribution coefficient as H2SO4 > CH3COONH4 > NH4Cl > NaCl > HNO3 > HCl > NH4NO3.Scandium was separated from alkali, alkaline earths, iron, zinc, cadmium, mercury, copper,

V. P. Mehta; S. M. Khopkar

1978-01-01

4

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

5

Separation and determination of rare earth elements by Dowex 2-X8 resin using sodium trimetaphosphate as elution agent.  

PubMed

The distribution coefficients of rare earth elements and thorium with Dowex 2-X8, 200-400 mesh, a strongly basic anion-exchange resin, have been determined regarding four different concentrations of sodium trimetaphosphate (3 x 10(-3), 5 x 10(-3), 7 x 10(-3) and 0.01 M). The separation of the rare earths and thorium obtained from an Australian monazite has been investigated by anion-exchange chromatography with sodium trimetaphosphate concentration gradient on a Dowex 2-X8 ion-exchange columns. The order of elution of the elements was the reverse of the order of elution of the same elements on Dowex 1 resin. The elution was investigated using 5 mg and 250 mg samples. In the separation of 5 mg samples, all elements were separated in 29 min. It has been seen that the elution peaks are narrow, tailing effects are very small, Dy and Y are well separated. Qualitative and quantitative determinations were realized by spectrofluorometry. PMID:10817370

Sungur, S K; Akseli, A

2000-04-01

6

Selective recovery of gold from secondary sources by Dowex-50-X8 sorbed Rhodamine-B resin.  

PubMed

Gold recovery from spent materials has been performed on modified cation-exchange resin. The modified resin was prepared by sorption of Rhodamine-B on Dowex-50-X8 (Na+) resin at pH 2.0. Distribution coefficients of gold ion have been determined with 15% (w/v) potassium chloride in different concentrations of hydrochloric acid. On the basis of Kd values quantitative separation of gold from secondary sources has been achieved. Gold(III) has been selectively separated from gold containing spent materials by column chromatography using modified ionexchange resin and the recovery was more than 92% compared to conventional cyanidation process. The results of the proposed method are suggestive of its applicability to other gold containing secondary sources. PMID:12556038

Syed, Sabir; Sharma, Lalit Mohan; Mohammad, A; Syed, Akheel Ahmed

2002-01-01

7

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

8

Pictet-spengler reaction using ion-exchange resin as a catalyst and support for 'catch and release' purification.  

PubMed

The Pictet-Spengler reaction between tryptamine and aldehydes was catalyzed by Dowex 50W-X4 acidic ion-exchange resin. The products were obtained from the resin in high purity by 'catch and release' without the need for separate chromatographic purification. PMID:21307579

Izumi, Minoru; Kido, Takeshi; Murakami, Miyu; Nakajima, Shuhei; Ganesan, A

2011-01-01

9

50 W photovoltaic system electronic control unit  

Microsoft Academic Search

The authors present an electronic regulator unit for small remote 50 W photovoltaic systems that can automatically and autonomously control energy and power for telecommunications systems of 12 V nominal DC voltage. The electronic control unit employs dual voltage operation, temperature compensation, and other circuits required for long-period work. The basic technical regulator data are maximal current of 4 A,

S. Baratka; M. Ruzinsky; L. Lukac; S. Trantalic

1989-01-01

10

Sodium-23 nuclear magnetic resonance of resins and mixed solvent systems  

NASA Astrophysics Data System (ADS)

The sodium-23 spin-lattice relaxation time (T1) was determined at 10 MHz on Dowex 50W-X2 ion exchanger resin as a function of the dielectric constant of the solvent. The relaxation time varied from 24.8 msec in distilled water (D=78.5) to values too short to determine in water-ethanol mixtures below a dielectric constant of 35. Similar studies were conducted on 250 mm sodium bisulfite (NaHSO3) in a series of aqueous-nonaqueous mixtures. The results indicate that T1 may be expressed as a function of the macroscopic dielectric constant for any binary solvent system. For systems with a dielectric constant greater than 65 the relationship is given by T1=a exp(bD), where a and b are constants for a particular solvent system.

Goldsmith, Michael; Hor, Doris; Damadian, Raymond

1976-09-01

11

Assessment of cadmium in aquatic sediment using dialysis samplers with ion-exchange-resin collection  

SciTech Connect

Simultaneously extracted metals (SEM) and acid volatile sulfide (AVS) show the potential for toxicity on the basis of their ratio. Accordingly, the authors spiked cadmium in a range for which Cd/AVS ratios were from 0.2 to 10 in the sediment with its weight about 8 kg in each batch. Dialysis samplers with a cation ion-exchange resin (Dowex 50W-X4) collection were used in a laboratory for the determination of free cadmium concentrations in pore water of the collected sediment. When equilibrium was reached among cadmium in pore water, sediment, and ion-exchange resin, cadmium exchanged onto resin phase was regenerated with 1 N hydrochloric acid (OPTIMA grade) and determined using an atomic absorption spectrophotometer (Zeeman 5000) with a graphite furnace accessory. Cadmium determined using the dialysis sampler is considered as free cadmium which is related to the metal bioavailability toward aquatic biota. The developed methodology provides a new technique for assessment of free metal in aquatic sediment systems.

Shi, B. [Kimberly-Clark Corp., Neenah, WI (United States). Environmental Technology; Allen, H.E. [Univ. of Delaware, Newark, DE (United States). Dept. of Civil and Environmental Engineering; Desnoyers, C. [ERM Program Management Co., Exton, PA (United States)

1998-05-01

12

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

Microsoft Academic Search

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

T. Ennil Köse; Ne?e Öztürk

2008-01-01

13

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

Microsoft Academic Search

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

T. E. Bekta?; N. Öztiirk

2004-01-01

14

Simultaneous voltammetric determination of acetaminophen and tramadol using Dowex50wx2 and gold nanoparticles modified glassy carbon paste electrode.  

PubMed

A glassy carbon paste electrode (GCPE) modified with a cation exchanger resin, Dowex50wx2 and gold nanoparticles (D50wx2-GNP-GCPE) has been developed for individual and simultaneous determination of acetaminophen (ACOP) and tramadol (TRA). The electrochemical behavior of both the molecules has been investigated employing cyclic voltammetry (CV), chronocoulometry (CC), electrochemical impedance spectroscopy (EIS) and adsorptive stripping square wave voltammetry (AdSSWV). The studies revealed that the oxidation of ACOP and TRA is facilitated at D50wx2-GNP-GCPE. Using AdSSWV, the method allowed simultaneous determination of ACOP and TRA in the linear working range of 3.34×10(-8) to 4.22×10(-5) M with detection limits of 4.71×10(-9) and 1.12×10(-8) M (S/N=3) for ACOP and TRA respectively. The prepared modified electrode shows several advantages such as simple preparation method, long-time stability, ease of preparation and regeneration of the electrode surface by simple polishing and excellent reproducibility. The high sensitivity and selectivity of D50wx2-GNP-GCPE were demonstrated by its practical application in the determination of both ACOP and TRA in pharmaceutical formulations, urine and blood serum samples. PMID:22023858

Sanghavi, Bankim J; Srivastava, Ashwini K

2011-11-14

15

Strontium in Milk. I. Removal by Means of Reverse-Flow Ion Exchange Columns1  

Microsoft Academic Search

Milk from two Jersey cows dosed orally with strontium ~ ~nd calcium ~ was mechani- cally separated into skimnfilk and cream. These radioactive isotopes were removed from the skimmilk by use of an upward-flow ion exchange resin column. Dowex 50W-X12, Dowex 50W-X4, and Duolite C-20 were used. The calcium form of ecah resin was more effec- tive in removal of

D. G. Easterly; B. J. Demott; R. G. Cragle

1960-01-01

16

Regeneration of Mixed Solvent by Ion Exchange Resin: Selective Removal of Chloride and Sulfate  

Microsoft Academic Search

The selective extraction of sulfate and chloride ions from mixed solvent solutions was investigated. The mixed solvents consisted of water and 50 to 100%?w (salt?free solvent) ethylene glycol. The extraction was measured for mixed solvent solutions containing only sulfate and chloride, and mixed solvent solutions saturated with trona (sodium sesquicarbonate, Na2CO3 · NaHCO3 · 2H2O(s). Three anion exchange resins, Dowex 1X8?50, Dowex 21K?Cl, and

Robert S. Gärtner

2005-01-01

17

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

18

Supported Pd–Cu catalysts in the water phase reduction of nitrates: Functional resin versus alumina  

Microsoft Academic Search

Pd–Cu bimetallic catalysts supported on the cationic resin Dowex 1×4 (gel type poly(styrene-co-divinylbenzene) with ?N(CH3)3+Cl? groups) and basic ?-Al2O3 were prepared by ion exchange and the incipient wetness impregnation method, respectively, and tested in the liquid-phase hydrogenation of nitrates in water. Various methods of the reduction of metal precursors were used. The effect of the preparation method, the temperature, the

Dana Gašparovi?ová; Milan Králik; Milan Hronec; Zuzana Vallušová; Hannelore Vinek; Benedetto Corain

2007-01-01

19

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

20

Boron removal from aqueous solutions by ion-exchange resin: column sorption-elution studies.  

PubMed

A column sorption-elution study was carried out by using a strong base anion-exchange resin (Dowex 2 x 8) for the removal of boron from aqueous solutions. The breakthrough curve was obtained as a function of feed flow rate and the total and breakthrough capacity values of the resin were calculated. The boron on the resin was quantitatively eluted with 0.5M HCl solution at different flow rates. Three consecutive sorption-elution-washing-regeneration-washing cycles were applied to the resin in order to investigate the reusability of the ion-exchange resin. Total capacity values remained almost the same after three sorption-elution-regeneration cycles. The Thomas and the Yoon-Nelson models were applied to experimental data to predict the breakthrough curves and to determine the characteristic column parameters required for process design. The results proved that the models would describe the breakthrough curves well. PMID:17716813

Köse, T Ennil; Oztürk, Ne?e

2008-04-01

21

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

22

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

PubMed Central

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

2013-01-01

23

Cement waste-form development for ion-exchange resins at the Rocky Flats Plant  

SciTech Connect

This report describes the development of a cement waste form to stabilize ion-exchange resins at Rocky Flats Environmental Technology Site (RFETS). These resins have an elevated potential for ignition due to inadequate wetness and contact with nitrates. The work focused on the preparation and performance evaluation of several Portland cement/resin formulations. The performance standards were chosen to address Waste Isolation Pilot Plant and Environmental Protection Agency Resource Conservation and Recovery Act requirements, compatibility with Rocky Flats equipment, and throughput efficiency. The work was performed with surrogate gel-type Dowex cation- and anion-exchange resins chosen to be representative of the resin inventory at RFETS. Work was initiated with nonactinide resins to establish formulation ranges that would meet performance standards. Results were then verified and refined with actinide-containing resins. The final recommended formulation that passed all performance standards was determined to be a cement/water/resin (C/W/R) wt % ratio of 63/27/10 at a pH of 9 to 12. The recommendations include the acceptable compositional ranges for each component of the C/W/R ratio. Also included in this report are a recommended procedure, an equipment list, and observations/suggestions for implementation at RFETS. In addition, information is included that explains why denitration of the resin is unnecessary for stabilizing its ignitability potential.

Veazey, G.W. [Los Alamos National Labs., NM (United States); Ames, R.L. [Rocky Flats Environmental Technology Site, Golden, CO (United States)

1997-03-01

24

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

Harvey, Brent M; Hoggard, Patrick E

2014-01-01

25

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

26

Devolatilization of polymer resins  

NASA Technical Reports Server (NTRS)

Commercial silicon resin was devolatilized by vacuum distillation, cured at room temperature and tested favorably for outgassing criteria. Applications of the devolatilized resin are potting compounds and conformal coatings.

Seidenberg, B.; Park, J.; Clatterbuck, C.

1972-01-01

27

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

28

Incombustible resin composition  

NASA Technical Reports Server (NTRS)

Incombustible resin compositions composed of aromatic compounds were obtained through (1) combustion polymer material and (2) bisphenol A or halogenated bisphenol A and bisphenol A diglycidl ether or halogenated bisphenol A diglycidyl ether. The aromatic compound is an adduct of bifunctional phenols and bifunctional epoxy resins.

Akima, T.

1982-01-01

29

Sorption of protons and metal ions from aqueous solutions by a strong-base anion-exchange resin loaded with sulphonated azo-dyes.  

PubMed

Two sulphonated azo-dyes, which bear a nitrogen donor atom in the diazo group and are known to complex many heavy metal ions in aqueous solution, have been found to be sorbed by a strong-base anion-exchange resin (Dowex 1-X8) simply by ion-exchange. The resin containing the dyes behaves like a chelating resin, able to sorb copper(II) and nickel(II) from aqueous solution, if the proper conditions are chosen. The acidity, ionic composition and volume of the aqueous solution, and the amount and nature of the sorbed ligand are the factors which determine the fraction of metal ion sorbed when the batch technique is used. The experimental results are interpreted by using a model of the resin based on the Donnan equilibrium concept, which allows prediction of the sorption conditions on the basis of some independently determined quantities, such as the protonation and complex formation constants in aqueous solution, and the activity of the counter-ion in the resin phase. The exchange of protons between the resin and the aqueous solution can also be explained with this model. PMID:18964547

Pesavento, M; Profumo, A; Biesuz, R

1988-06-01

30

Development of resins for composites by resin transfer molding  

NASA Technical Reports Server (NTRS)

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

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

1991-01-01

31

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

32

Biocidal quaternary ammonium resin  

NASA Technical Reports Server (NTRS)

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

Janauer, G. E.

1983-01-01

33

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

PubMed

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

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

2005-07-01

34

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

PubMed

The purpose of this study was to selectively remove chromium and copper from CCA-treated wood acid leachates (initial concentrations of 447-651 mg As l(-1), 374-453 mg Cu l(-1) and 335-622 mg Cr l(-1)) using ion exchange resins and precipitation techniques. Batch experiments revealed that the chelating resin Dowex M4195 had a high copper selectivity in the presence of chromium while the Amberlite IR120 resin had a high chromium sorption capacity. Combining M4195 and IR120 resins in four successive columns, made with Plexiglas tube, led to 96% copper extraction and 68% chromium extraction. NH(4)OH (4M) efficiently eluted copper from the chelating resin while H(2)SO(4) (10%v/v) was used for IR120 resin elution. Copper and chromium recovery by elution reached 94% and 81%, respectively. Successive sorption and elution steps using M4195 and IR120 ion exchange resins presented similar metal removal capacities over the five cycles. No resin deterioration was observed but the results suggested arsenic bulk diffusion into the M4195 resin. Successive treatments of CCA-treated wood leachate with M4195 and IR120 allowed for copper and chromium removal while arsenic could be extracted by coagulation treatment with ferric chloride and precipitation with Ca(OH)(2) at pH 5.7. This final process led to 99.9% arsenic removal. The final effluent contained less than 1 mg l(-1) of arsenic, chromium and copper. PMID:19446391

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

2009-09-30

35

Acetylene terminated matrix resins  

NASA Technical Reports Server (NTRS)

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

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

1985-01-01

36

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

Code of Federal Regulations, 2010 CFR

...Polyesters *Furan Resins Glyoxal-Urea Formaldehyde Textile Resin *Ketone-Formaldehyde Resins *Melamine Resins *Phenolic Resins *Polyacetal Resins Polyacrylamide *Polyurethane Prepolymers *Polyurethane Resins...

2010-07-01

37

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

38

High-performance bismaleimide resin for resin film infusion  

Microsoft Academic Search

A novel high-performance resin system, suitable for resin film infusion (RFI) process, has been developed. It was prepared from N,N?-diphenylbismaleimide, o,o?-diallylbisphenol A, and polyethylsulfone. The resin and its composite, reinforced by a glass fiber cloth, were prepared and characterized in detail. The results showed that the prepared resin film is stable at room temperature, the infusion temperature is 120°C, and

Guozheng Liang; Dong Wang

2002-01-01

39

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

40

A theoretical model for the separation of glucose and fructose mixtures by using a semicontinuous chromatographic refiner  

SciTech Connect

The separation of a glucose and fructose mixture was experimentally performed by using a semicontinuous chromatographic refiner (SCCR) packed with Ca{sup 2+} ion in the form of DOWEX 50W 12X resin. The plug flow model with velocity-dependent mass transfer resistance was resistance was presented for calculating both products and on-concentrations in the SCCR unit, and the validity of the model was experimentally confirmed.

Lee, Kwang Nam; Lee, Won Kook (Korea Advance Inst., Seoul (Korea))

1992-03-01

41

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

42

Glycoprotein Enrichment Resin User Manual  

E-print Network

Glycoprotein Enrichment Resin User Manual Cat. No. 635647 PT4050-1 (PR912675) Published 14 January Laboratories, Inc. Version No. PR912675 ATakara Bio Company 2 Glycoprotein Enrichment Resin User Manual I.................................................................................................4 IV. Glycoprotein Enrichment

Lebendiker, Mario

43

Phosphonic acid based 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.

1995-09-12

44

Phosphonic acid based exchange resins  

DOEpatents

An ion exchange resin 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.

Horwitz, E. Philip (Naperville, IL); Alexandratos, Spiro D. (Knoxville, TN); Gatrone, Ralph C. (Naperville, IL); Chiarizia, Ronato (Oak Park, IL)

1995-01-01

45

Progress in DUV resins  

NASA Astrophysics Data System (ADS)

Starting from general arguments on the relation of polymer structure, transparency at 248 nm, resin hydrophilicity and resist dissolution characteristics, binder systems for novel DUV resists are presented, and the results of their lithographic evaluation are discussed. Phenolic polymers studied include homo- and copolymers of 2-, 3-, and 4- hydroxystyrenes and of their alkyl substituted derivatives for three- component systems, as well as 2- and 4-hydroxyphenylmethacrylates for use in two-component t-BOC-type resists. As an alternative nonphenolic resin, the performance of a maleimide/styrene copolymer in a two- component system is discussed.

Przybilla, Klaus J.; Roeschert, Heinz; Spiess, Walter; Eckes, Charlotte; Chatterjee, Subhankar; Khanna, Dinesh N.; Pawlowski, Georg; Dammel, Ralph R.

1991-06-01

46

Fractionation of sulphite spent liquor for biochemical processing using ion exchange resins.  

PubMed

Sulphite spent liquor (SSL) is a side product from acidic sulphite pulping of wood, which organic counterpart is composed mainly by lignosulphonates (LS) and sugars. The last are a prominent substrate for the bioprocessing although a previous purification step is necessary to eliminate microbial inhibitors. In this study a fractionation of hardwood SSL (HSSL) has been accomplished employing ion exchange resins in order to separate sugars fraction from concomitant inhibitors: LS, acetic acid, furan derivatives, phenolics, acetic acid and excess of inorganic salts. The fractionation of HSSL has been carried out using two fixed-bed ion exchangers in series (cationic+anionic). The first cation exchange column packed with Dowex 50WX2 resin was able to eliminate free cations and partially separate sugars from high molecular weight LS and furan derivatives. The second anion exchange column packed with Amberlite IRA-96 sorbed remaining LS, phenolics and acetic acid. Overall, the series arrangement under investigation has removed 99.99% of Mg(2+), 99.0% of Ca(2+), 99.6% of LS, and 100% of acetic acid, whereas the yield of recovered sugars was at least 72% of their total amount in HSSL. PMID:22465600

Fernandes, D L A; Silva, C M; Xavier, A M R B; Evtuguin, D V

2012-12-31

47

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

48

Nontoxic Resins Advance Aerospace Manufacturing  

NASA Technical Reports Server (NTRS)

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

2009-01-01

49

Sodium Concentration Measurement during Hemodialysis through Ion-Exchange Resin and Conductivity Measure Approach: In Vitro Experiments  

PubMed Central

Sodium measurement during hemodialysis treatment is important to preserve the patient from clinical events related to hypo- or hyper-natremia Usually, sodium measurement is performed through laboratory equipment which is typically expensive, and requires manual intervention. We propose a new method, based on conductivity measurement after treatment of dialysate solution through ion-exchange resin. To test this method, we performed in vitro experiments. We prepared 40 ml sodium chloride (NaCl) samples at 280, 140, 70, 35, 17.5, 8.75, 4.375 mEq/l, and some “mixed samples”, i.e., with added potassium chloride (KCl) at different concentrations (4.375-17.5 mEq/l), to simulate the confounding factors in a conductivity-based sodium measurement. We measured the conductivity of all samples. Afterwards, each sample was treated for 1 min with 1 g of Dowex G-26 resin, and conductivity was measured again. On average, the difference in the conductivity between mixed samples and corresponding pure NaCl samples (at the same NaCl concentration) was 20.9%. After treatment with the exchange resin, it was 14.7%, i.e., 42% lower. Similar experiments were performed with calcium chloride and magnesium chloride as confounding factors, with similar results. We also performed some experiments on actual dialysate solution during hemodialysis sessions in 15 patients, and found that the correlation between conductivity measures and sodium concentration improved after resin treatment (R=0.839 before treatment, R=0.924 after treatment, P<0.0001). We conclude that ion-exchange resin treatment coupled with conductivity measures may improve the measurement of sodium compared to conductivity measures alone, and may become a possible simple approach for continuous and automatic sodium measurement during hemodialysis. PMID:23844253

Tura, Andrea; Sbrignadello, Stefano; Mambelli, Emanuele; Ravazzani, Paolo; Santoro, Antonio; Pacini, Giovanni

2013-01-01

50

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

Code of Federal Regulations, 2012 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2012-04-01

51

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

Code of Federal Regulations, 2010 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2010-04-01

52

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

Code of Federal Regulations, 2014 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2014-04-01

53

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

Code of Federal Regulations, 2011 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2011-04-01

54

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

Code of Federal Regulations, 2013 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2013-04-01

55

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

56

Biological Ion Exchanger Resins  

PubMed Central

Utilizing Escherichia coli as the prototype of an ion-accumulating cell, the ion exchange isotherm is introduced as a concise method of characterizing biological ion exchange events. The ion exchange isotherm for the alkali cation exchange, K ? Na, is described. The total charge profile of this bacterium is compiled and compared for bacteria in the Na form and in the K form. Macromolecule fixed charge was found to provide 80% of the counter ions that pair with potassium. Therefore, in its physiological state, 80% of the cell potassium in E. coli is associated with an ion exchange site on a macromolecule. The primary cation exchange sites are found to be about equally divided between carboxylate and phosphate sites indicating that E. coli is a bifunctional resin with respect to cation exchange. During substrate-dependent cation accumulation (“active transport”), phosphate esters and organic acids were shown to accumulate. One may conclude that the role of intermediate metabolism in “active transport” is to increase the ion exchange capacity of the biological resin by the production of charged metabolites that sorb to the framework of the resin. PMID:4943652

Damadian, Raymond

1971-01-01

57

System for removing contaminants from plastic resin  

DOEpatents

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

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

2010-11-23

58

Advanced thermoplastic resins, phase 1  

NASA Technical Reports Server (NTRS)

Eight thermoplastic polyimide resin systems were evaluated as composite matrix materials. Two resins were selected for more extensive mechanical testing and both were versions of LaRC-TPI (Langley Research Center - Thermoplastic Polyimide). One resin was made with LaRC-TPI and contained 2 weight percent of a di(amic acid) dopant as a melt flow aid. The second system was a 1:1 slurry of semicrystalline LaRC-TPI powder in a polyimidesulfone resin diglyme solution. The LaRC-TPI powder melts during processing and increases the melt flow of the resin. Testing included dynamic mechanical analysis, tension and compression testing, and compression-after-impact testing. The test results demonstrated that the LaRC-TPI resins have very good properties compared to other thermoplastics, and that they are promising matrix materials for advanced composite structures.

Hendricks, C. L.; Hill, S. G.; Falcone, A.; Gerken, N. T.

1991-01-01

59

Vitrification of ion exchange resins  

DOEpatents

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

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

2001-01-01

60

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... temperature units, and vary depending on the resin, the mold and the molding process. Typically the drier is set for the worst possible conditions. So there are opportunities for energy savings. This study conducted by Southern California Edison Company...

Joseph, B.; Thuro, G.

61

Phosphorus-containing bisimide resins  

NASA Technical Reports Server (NTRS)

The production of fire-resistant resins particularly useful for making laminates with inorganic fibers such as graphite fibers is discussed. The resins are by (1) condensation of an ethylenically unsaturated cyclic anhydride with a bis(diaminophenyl) phosphine oxide, and (2) by addition polymerization of the bisimide so obtained. Up to about 50%, on a molar basis, of benzophenonetetracarboxylic acid anhydride can be substituted for some of the cyclic anhydride to alter the properties of the products. Graphite cloth laminates made with these resins show 800 C char yields greater than 70% by weight in nitrogen. Limiting oxygen indexes of more than 100% are determined for these resins.

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

1981-01-01

62

Indirect resin composites  

PubMed Central

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

Nandini, Suresh

2010-01-01

63

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

64

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

PubMed Central

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

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

2015-01-01

65

Efficiencies and Optimization of Weak Base Anion Ion-Exchange Resin for Groundwater Hexavalent Chromium Removal at Hanford  

SciTech Connect

The U.S. Department of Energy’s (DOE’s) contractor, CH2M HILL Plateau Remediation Company, has successfully converted a series of groundwater treatment facilities to use a new treatment resin that is delivering more than $3 million in annual cost savings and efficiency in treating groundwater contamination at the DOE Hanford Site in southeastern Washington State. During the production era, the nuclear reactors at the Hanford Site required a continuous supply of high-quality cooling water during operations. Cooling water consumption ranged from about 151,417 to 378,541 L/min (40,000 to 100,000 gal/min) per reactor, depending on specific operating conditions. Water from the Columbia River was filtered and treated chemically prior to use as cooling water, including the addition of sodium dichromate as a corrosion inhibitor. Hexavalent chromium was the primary component of the sodium dichromate and was introduced into the groundwater at the Hanford Site as a result of planned and unplanned discharges from the reactors starting in 1944. Groundwater contamination by hexavalent chromium and other contaminants related to nuclear reactor operations resulted in the need for groundwater remedial actions within the Hanford Site reactor areas. Beginning in 1995, groundwater treatment methods were evaluated, leading to the use of pump-and-treat facilities with ion exchange using Dowex™ 21K, a regenerable, strong-base anion exchange resin. This required regeneration of the resin, which was performed offsite. In 2008, DOE recognized that regulatory agreements would require significant expansion for the groundwater chromium treatment capacity. As a result, CH2M HILL performed testing at the Hanford Site in 2009 and 2010 to demonstrate resin performance in the specific groundwater chemistry at different waste sites. The testing demonstrated that a weak-base anion, single-use resin, specifically ResinTech SIR-700 ®, was effective at removing chromium, had a significantly higher capacity, could be disposed of efficiently onsite, and would eliminate the complexities and programmatic risks from sampling, packaging, transportation, and return of resin for regeneration.

Nesham, Dean O. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Ivarson, Kristine A. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Hanson, James P. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Miller, Charles W. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Meyers, P. [USDOE, Richland Operations Office, WA (United States); Jaschke, Naomi M. [USDOE, Richland Operations Office, WA (United States)

2014-02-03

66

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

67

Reduction of polyester resin shrinkage by means of epoxy resin—I. Epoxy resin modified with acids  

NASA Astrophysics Data System (ADS)

An attempt was made to decrease the shrinkage of unsaturated polyester resin, taking place during radiation-induced curing, by the addition of epoxy resin. In order to combine chemically both resins, the epoxy component was modified with cinnamic and acrylic acids. A composition of 90 parts of polyesster resin, 10 parts of epoxy resin modified with cinnamic acid, and 150 parts of a silica filler showed a volume shrinkage of 1.2%.

Pietrzak, M.; Brzostowski, A.

68

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

69

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

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

1997-04-08

70

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

71

Flammability screening tests of resins  

NASA Technical Reports Server (NTRS)

Selected flammability characteristics of glass cloth laminates of thermosetting resins are evaluated. A protocol for the evaluation of the flammability hazards presented by glass cloth laminates of thermosetting resins and the usefulness of that protocol with two laminates are presented. The glass laminates of an epoxy resin, M-751 are evaluated for: (1) determination of smoke generation from the laminates; (2) analysis of products of oxidative degradation of the laminates; (3) determination of minimum oxygen necessary to maintain flaming oxidation; (4) evaluation of toxicological hazards.

Arhart, R. W.; Farrar, D. G.; Hughes, B. M.

1979-01-01

72

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

73

Epoxy hydantoins as matrix resins  

NASA Technical Reports Server (NTRS)

Tensile strength and fracture toughness of castings of the hydantoin resins cured with methylenedianiline are significantly higher than MY 720 control castings. Water absorption of an ethyl, amyl hydantoin formulation is 2.1 percent at equilibrium and Tg's are about 160 C, approximately 15 deg below the final cure temperature. Two series of urethane and ester-extended hydantoin epoxy resins were synthesized to determine the effect of crosslink density and functional groups on properties. Castings cured with methylenedianiline or with hexahydrophthalic anhydride were made from these compounds and evaluated. The glass transition temperatures, tensile strengths and moduli, and fracture toughness values were all much lower than that of the simple hydantoin epoxy resins. Using a methylene bishydantoin epoxy with a more rigid structure gave brittle, low-energy fractures, while a more flexible, ethoxy-extended hydantoin epoxy resin gave a very low Tg.

Weiss, J.

1983-01-01

74

Liquid monobenzoxazine based resin system  

DOEpatents

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

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

2014-10-07

75

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

Code of Federal Regulations, 2014 CFR

...Product groups are indicated with an asterisk (*). *Alkyd Resins Dicyanodiamide Resin *Epoxy Resins *Fumaric Acid Polyesters *Furan Resins Glyoxal-Urea Formaldehyde Textile Resin *Ketone-Formaldehyde Resins *Melamine Resins...

2014-07-01

76

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

Code of Federal Regulations, 2013 CFR

...Product groups are indicated with an asterisk (*). *Alkyd Resins Dicyanodiamide Resin *Epoxy Resins *Fumaric Acid Polyesters *Furan Resins Glyoxal-Urea Formaldehyde Textile Resin *Ketone-Formaldehyde Resins *Melamine Resins...

2013-07-01

77

Recovery of 99mTc from Na2[99Mo]MoO4 solution obtained from reactor-produced (n,gamma) 99Mo using a tiny Dowex-1 column in tandem with a small alumina column.  

PubMed

A simple separation technique of (99m)Tc from Na(2)[(99)Mo]MoO(4) in sodium hydroxide solution obtained from the (98)Mo(n,gamma)(99)Mo reaction is described. Low to medium specific activity (99)Mo-molybdate solution of 7.4-18.5GBq (200-500mCi) in sodium hydroxide was passed through a tiny Dowex-1 column (25mg) to separate the (99m)Tc from the (99)Mo; subsequently the (99m)Tc was eluted from the Dowex 1 column with tetrabutylammonium bromide (TBAB) solution (1mg/5ml methylene chloride). The TBAB solution was passed through a small alumina column (1.5g) where the (99m)Tc is retained and separated from TBAB and CH(2)Cl(2). Technetium-99m from the alumina column was finally eluted with 5ml saline leaving any traces of (99)Mo on the alumina column. The separation yield was about 90% (n=10). The method has applicability for decontamination of (99g)Tc from spent (99)Mo waste solution and recovery of (99g)Tc for research use. The procedure should also be equally applicable for recovery of (188)ReO(4) from (188)WO(4) in a radioisotope laboratory. PMID:18703342

Chattopadhyay, Sankha; Das, Sujata Saha; Das, Malay K; Goomer, Naresh C

2008-12-01

78

Low Melt Viscosity Resins for Resin Transfer Molding  

NASA Technical Reports Server (NTRS)

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

Harris, Frank W.

2002-01-01

79

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2010 CFR

...fluoride resins. Polyvinylidene fluoride resins may be safely used...section, the polyvinylidene fluoride resins consist of basic resins...polymerization of vinylidene fluoride. (b) The finished food-contact...with the solvents distilled water, 50 percent (by...

2010-04-01

80

Thermal debracketing of orthodontic resins.  

PubMed

Ten commercial brands of orthodontic bonding materials representing three modes of delivery systems (two-paste, no-mix, and powder/liquid) were used to bond stainless steel brackets to bovine teeth. Heat was applied to the bracket, and the temperature at debonding was noted for each type of resin. The two-paste systems required a higher temperature to debond than did the no-mix systems. The powder/liquid system required the lowest temperature. There is a direct relationship between filler content and debonding temperature. There is an inverse exponential relationship between debonding temperature and load needed to cause debracketing. Room-temperature debonding showed failure at the bracket/resin interface with evidence of cohesive enamel fracture. Thermal debonding showed no evidence of overt enamel fracture, and failure site shifted toward the tooth/resin interface. Ceramic brackets required almost twice the time to debracket than did stainless steel brackets. PMID:2194390

Rueggeberg, F A; Lockwood, P

1990-07-01

81

Soluble high molecular weight polyimide resins  

NASA Technical Reports Server (NTRS)

High molecular weight polyimide resins have greater than 20 percent /by weight/ solubility in polar organic solvents. They permit fabrication into films, fibers, coatings, reinforced composite, and adhesive product forms. Characterization properties for one typical polyimide resin are given.

Jones, R. J.; Lubowitz, H. R.

1970-01-01

82

Phosphonic acid based ion exchange resins  

DOEpatents

An ion exchange resin 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.

Horwitz, E. Philip (Naperville, IL); Alexandratos, Spiro D. (Knoxville, TN); Gatrone, Ralph C. (Naperville, IL); Chiarizia, Ronato (Oak Park, IL)

1996-01-01

83

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin applicator. (a) Identification. A resin applicator is a brushlike device...

2010-04-01

84

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

85

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2013 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...

2013-04-01

86

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 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...

2010-04-01

87

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2012 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...

2012-04-01

88

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

89

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2014 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 a...

2014-04-01

90

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2011 CFR

...Identification. A resin applicator is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth shade material. (b) Classification. Class I (general controls). The device is exempt...

2011-04-01

91

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2011 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2011-04-01

92

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2014 CFR

...HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2014-04-01

93

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2010 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2010-04-01

94

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2013 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2013-04-01

95

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2012 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2012-04-01

96

SRM filament wound case resin characterization studies  

NASA Technical Reports Server (NTRS)

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

Chou, L. W.

1985-01-01

97

Method of removing contaminants from plastic resins  

DOEpatents

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

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

2008-11-18

98

Method for removing contaminants from plastic resin  

DOEpatents

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

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

2008-12-30

99

Method of removing contaminants from plastic resins  

DOEpatents

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

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

2007-08-07

100

Synthesis of improved phenolic resins  

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

101

Metal Affinity Resins User Manual  

E-print Network

BD TALONTM Metal Affinity Resins User Manual PT1320-1 (PR34731) Published 29 April 2003 BD Biosciences #12;BD Biosciences Clontech www.bdbiosciences.com Protocol No. PT1320-1 2 Version No. PR34731 BD III. Additional Materials Required 13 IV. Buffers for BD TALONTM Purification & Buffer Kits 17 V

Lebendiker, Mario

102

Process for curing bismaleimide resins  

NASA Technical Reports Server (NTRS)

This invention relates to vinyl pyridine group containing compounds and oligomers, their advantageous copolymerization with bismaleimide resins, and the formation of reinforced composites based on these copolymers. When vinyl pyridines including vinyl stilbazole materials and vinyl styrylpyridine oligomer materials are admixed with bismaleimides and cured to form copolymers the cure temperatures of the copolymers are substantially below the cure temperatures of the bismaleimides alone.

Parker, John A. (inventor); OTHY S.imides alone. (inventor)

1986-01-01

103

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

104

A Method for Characterizing PMR-15 Resin  

NASA Technical Reports Server (NTRS)

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

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

1986-01-01

105

Phenoxy resins containing pendent ethynyl groups  

NASA Technical Reports Server (NTRS)

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

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

1984-01-01

106

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

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

107

Advanced thermoplastic resins, phase 2  

NASA Technical Reports Server (NTRS)

High temperature structural resins are required for use on advanced aerospace vehicles as adhesives and composite matrices. NASA-Langley developed polyimide resins were evaluated as high temperature structural adhesives for metal to metal bonding and as composite matrices. Adhesive tapes were prepared on glass scrim fabric from solutions of polyamide acids of the semicrystalline polyimide LARC-CPI, developed at the NASA-Langley Research Center. Using 6Al-4V titanium adherends, high lap shear bond strengths were obtained at ambient temperature (45.2 MPa, 6550 psi) and acceptable strengths were obtained at elevated temperature (14.0 MPa, 2030 psi) using the Pasa-Jell 107 conversion coating on the titanium and a bonding pressure of 1.38 MPa (200 psi). Average zero degree composite tensile and compressive strengths of 1290 MPa (187 ksi) and 883 MPa (128 ksi) respectively were obtained at ambient temperature with unsized AS-4 carbon fiber reinforcement.

Brown, A. M.; Hill, S. G.; Falcone, A.

1991-01-01

108

High Temperature Transfer Molding Resins  

NASA Technical Reports Server (NTRS)

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

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

2000-01-01

109

Phosphorus-containing imide resins  

NASA Technical Reports Server (NTRS)

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

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

1984-01-01

110

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

111

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

112

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

113

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

114

Novel silica-based ion exchange resin  

SciTech Connect

Eichrom`s highly successful Diphonixo resin resembles a conventional ion exchange resin in its use of sulfonic acid ligands on a styrene- divinylbenzene matrix. Diphonix resin exhibits rapid exchange kinetics that allow economical operation of ion exchange systems. Unlike conventional resins, Diphonix resin contains chelating ligands that are diphosphonic acid groups that recognize and remove the targeted metals and reject the more common elements such as sodium, calcium and magnesium. This latter property makes Diphonix ideal for many industrial scale applications, including those involving waste treatment. For treatment of low-level, transuranic (TRU) and high- level radioactive wastes, Diphonix`s polystyrene backbone hinders its application due to radiolytic stability of the carbon-hydrogen bonds and lack of compatibility with expected vitrification schemes. Polystyrene-based Diphonix is approximately 60% carbon- hydrogen. In response to an identified need within the Department of Energy for a resin with the positive attributes of Diphonix that also exhibits greater radiolytic stability and final waste form compatibility, Eichrom has successfully developed a new, silica-based resin version of Diphonix. Target application for this new resin is for use in environmental restoration and waste management situations involving the processing of low-level, transuranic and high-level radioactive wastes. The resin can also be used for processing liquid mixed waste (waste that contains low level radioactivity and hazardous constituents) including mixed wastes contaminated with organic compounds. Silica-based Diphonix is only 10% carbon-hydrogen, with the bulk of the matrix silica.

NONE

1997-11-01

115

Advanced resin systems for graphite epoxy composites  

NASA Technical Reports Server (NTRS)

The value of resin/carbon fiber composites as lightweight structures for aircraft and other vehicle applications is dependent on many properties: environmental stability, strength, toughness, resistance to burning, smoke produced when burning, raw material costs, and complexity of processing. A number of woven carbon fiber and epoxy resin composites were made. The epoxy resin was commercially available tetraglycidylmethylene dianiline. In addition, composites were made using epoxy resin modified with amine and carboxyl terminated butadiene acrylonitrile copolymer. Strength and toughness in flexure as well as oxygen index flammability and NBS smoke chamber tests of the composites are reported.

Gilwee, W. J.; Jayarajan, A.

1980-01-01

116

Microbiological Study of Water-Softener Resins  

PubMed Central

Microbial identification using effluents backflushed from exhausted urban and rural tank resins and cleaned resins containing the sulfonated copolymer of styrene and divinylbenzene (SDB) were completed, along with microbial assessment of the concentrated stock salt brine. Forty-four different bacterial and fungal genera were identified. Extensive biochemical and animal virulence tests completed on one of the six bacterial salt brine isolates indicated a pathogenic staphylococcal strain. The retention of Staphylococcus aureus, a Flavobacterium sp, and Escherichia coli B bacteriophage was demonstrated both by using the nonexhausted sodium-regenerated resin and by using the same resin exchanged with different mono-, di-, and trivalent cations. Effluent counts completed after bacterial seepage through the resins indicated the Pb++ exchanged resin removed 55% of the bacteria; Na+, Fe++, and Al+++ removed 31 to 36% and Ca++ and Cu++ removed about 10 to 15%. Seventy per cent or more of the bacteriophage was removed by Fe++, Cu++, and Al+++, whereas the Ca++ and Na++ cations removed 25 to 31%. Over a 77-day period, nonsterile tap water was passed through bacterial seeded and uninoculated SDB (Na) resin columns. Effluent and resin elution counts demonstrated the growth and survival of 2 different bacteria per column. Increased bacterial retention, survival, and multiplication occurred concomitantly with accumulation of organic and inorganic materials and the Ca++ and Mg++ cations from the tap water. Furthermore, microbial elution from resin particles taken from column depths of 1, 8, and 16 cm indicated a bacterial diminution with increasing depths. PMID:5373675

Stamm, John M.; Engelhard, Warren E.; Parsons, James E.

1969-01-01

117

75 FR 67105 - Granular Polytetrafluoroethylene Resin From Italy and Japan  

Federal Register 2010, 2011, 2012, 2013, 2014

...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

118

40 CFR 721.5908 - Modified phenolic resin (generic).  

Code of Federal Regulations, 2010 CFR

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

2010-07-01

119

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2009-04-01 true Phenolic resins in molded articles. 177.2410 Section...Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be...

2010-04-01

120

40 CFR 721.5905 - Modified phenolic resin (generic).  

Code of Federal Regulations, 2010 CFR

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

2010-07-01

121

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

Code of Federal Regulations, 2010 CFR

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

2010-07-01

122

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

123

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

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2012-07-01

124

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

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2014-07-01

125

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

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2011-07-01

126

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2013-07-01

127

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Root canal filling resin. 872.3820 Section 872... Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of...

2012-04-01

128

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Root canal filling resin. 872.3820 Section 872... Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of...

2014-04-01

129

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Resin tooth bonding agent. 872.3200 Section 872...Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device material,...

2011-04-01

130

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Resin tooth bonding agent. 872.3200 Section 872...Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device material,...

2010-04-01

131

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2011 CFR

... false Phenolic resins in molded articles. 177.2410 Section 177.2410...Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified...

2011-04-01

132

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

133

Biocompatibility of resin-modified filling materials.  

PubMed

Increasing numbers of resin-based dental restorations have been placed over the past decade. During this same period, the public interest in the local and especially systemic adverse effects caused by dental materials has increased significantly. It has been found that each resin-based material releases several components into the oral environment. In particular, the comonomer, triethyleneglycol di-methacrylate (TEGDMA), and the 'hydrophilic' monomer, 2-hydroxy-ethyl-methacrylate (HEMA), are leached out from various composite resins and 'adhesive' materials (e.g., resin-modified glass-ionomer cements [GICs] and dentin adhesives) in considerable amounts during the first 24 hours after polymerization. Numerous unbound resin components may leach into saliva during the initial phase after polymerization, and later, due to degradation or erosion of the resinous restoration. Those substances may be systemically distributed and could potentially cause adverse systemic effects in patients. In addition, absorption of organic substances from unpolymerized material, through unprotected skin, due to manual contact may pose a special risk for dental personnel. This is borne out by the increasing numbers of dental nurses, technicians, and dentists who present with allergic reactions to one or more resin components, like HEMA, glutaraldehyde, ethyleneglycol di-methacrylate (EGDMA), and dibenzoyl peroxide (DPO). However, it must be emphasized that, except for conventional composite resins, data reported on the release of substances from resin-based materials are scarce. There is very little reliable information with respect to the biological interactions between resin components and various tissues. Those interactions may be either protective, like absorption to dentin, or detrimental, e.g., inflammatory reactions of soft tissues. Microbial effects have also been observed which may contribute indirectly to caries and irritation of the pulp. Therefore, it is critical, both for our patients and for the profession, that the biological effects of resin-based filling materials be clarified in the near future. PMID:11021634

Geurtsen, W

2000-01-01

134

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

135

Phosphorus-containing imide resins  

NASA Technical Reports Server (NTRS)

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

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

1985-01-01

136

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2012 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2012-04-01

137

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2013 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2013-04-01

138

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2011 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2011-04-01

139

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2014 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2014-04-01

140

Surface preparations for metal frameworks of composite resin veneered prostheses made with an adhesive opaque resin.  

PubMed

Bond strengths of a laboratory developed light-cured composite resin to dental casting alloys were evaluated with a new adhesive opaque resin. The metal specimens were type III gold, nickel-chromium, and cobalt-chromium alloys, while the surface treatments for bonding were heating, Sn plating, and ion coating. The cast metal specimens were "particle blasted" with aluminum oxide and were surface treated. Adhesive 4-META/MMA-TBB opaque resin was applied and a light-cured composite resin was placed over the opaque layer. The prepared specimens were thermocycled in water and shear bond strengths were recorded. The light-cured composite resin was bonded strongly to heated or Sn-plated type III alloy with 4-META/MMA-TBB opaque resin. Copper ion coating in a sputter coater was effective for all three alloys, with only slightly diminished bond strengths. These methods were satisfactory for making composite resin veneered prostheses. PMID:1941662

Matsumura, H; Kawahara, M; Tanaka, T; Atsuta, M

1991-07-01

141

Modified resins for solid-phase extraction  

DOEpatents

A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

Fritz, James S. (Ames, IA); Sun, Jeffrey J. (Ames, IA)

1991-12-10

142

Modified resins for solid-phase extraction  

DOEpatents

A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

Fritz, James S. (Ames, IA); Sun, Jeffrey J. (Ames, IA)

1993-07-27

143

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2011 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2011-04-01

144

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2014 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2014-04-01

145

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2012 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2012-04-01

146

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2013 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2013-04-01

147

IMPROVEMENTS IN EPOXY RESIN EMBEDDING METHODS  

Microsoft Academic Search

Epoxy embedding methods of Glauert and Kushida have been modified so as to yield rapid, reproducible, and convenient embedding methods for electron microscopy. The sections are robust and tissue damage is less than with methacrylate embedding. It has become apparent that there is considerable advantage in using epoxy resins in embedding tissues for electron microscopy. Compared to methacrylates, epoxy resins

JOHN H. LUFT

148

Volumetric polymerization shrinkage of contemporary composite resins.  

PubMed

The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill Magic, Alert, and Solitaire) to determine whether there are differences among these materials. The tests were conducted with precision of 0.1 mg. The volumetric shrinkage was measured by hydrostatic weighing before and after polymerization and calculated by known mathematical equations. One-way ANOVA (á = 0.05) was used to determine statistically significant differences in volumetric shrinkage among the tested composite resins. Suprafill (1.87+/-0.01) and Definite (1.89+/-0.01) shrank significantly less than the other composite resins. SureFil (2.01+/-0.06), Filtek Z250 (1.99+/-0.03), and Fill Magic (2.02+/-0.02) presented intermediate levels of polymerization shrinkage. Alert and Solitaire presented the highest degree of polymerization shrinkage. Knowing the polymerization shrinkage rates of the commercially available composite resins, the dentist would be able to choose between using composite resins with lower polymerization shrinkage rates or adopting technical or operational procedures to minimize the adverse effects deriving from resin contraction during light-activation. PMID:19089177

Nagem Filho, Halim; Nagem, Haline Drumond; Francisconi, Paulo Afonso Silveira; Franco, Eduardo Batista; Mondelli, Rafael Francisco Lia; Coutinho, Kennedy Queiroz

2007-10-01

149

Silicone modified resins for graphite fiber laminates  

NASA Technical Reports Server (NTRS)

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

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

1980-01-01

150

Method of curing unsaturated polymer resin  

Microsoft Academic Search

An unsaturated polyester resin in contact with a vulcanized rubber is ; haadened by ionization radiation. The unsaturated polyester resin includes ; unsaturated dibasic acid such as maleic anhydride and phthalic anhydride, ; reaction products with dihydric alcohols such as ethylene glycol and propylene ; glycol, the compounds that can be obtained by dissolving into vinyl monomer such ; as

K. Goto; K. Araki; T. Sasaki

1970-01-01

151

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

152

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2012 CFR

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

2012-04-01

153

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2010 CFR

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

2010-04-01

154

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2011 CFR

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

2011-04-01

155

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2014 CFR

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

2014-04-01

156

TALONTM Resins I. List of Components  

E-print Network

) 5 2-ml Disposable Gravity Columns 1 10-ml Disposable Gravity Column · TALONTM Buffer Kit (#K1252 Imidazole, pH 7) · TALONTM 2-ml Disposable Gravity Columns (#8903-1) TALONTMResinProtocol 37BD Biosciences to TALON Resins, which decreases resin specific capacity and the final purity of your target protein. You

Lebendiker, Mario

157

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

158

Reduction of polyester resin shrinkage by means of epoxy resin—II. Epoxy resin modified with acrylamide and N-hydroxymethyloloacrylamide  

NASA Astrophysics Data System (ADS)

The possibility was investigated of reducing the shrinkage of unsaturated polyester resin taking place in radiation-induced curing, by the addition of epoxy resin. In order to combine chemically both resins, the epoxy component was modified by introducing unsaturated bonds via acrylamide and N-hydroxymethyloloacrylamide. A composition of 90% unsaturated polyester resin and 10% acrylamide-modified epoxy resin, filled with silica (1:1.5), showed a volume shrinkage below 2%.

Pietrzak, M.; Brzostowski, A.

159

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

160

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

161

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

162

Characterizing Delamination Resistance of Toughened Resin Composites  

NASA Technical Reports Server (NTRS)

The delamination resistance of toughened resin composites was studied. Both the edge delamination test (EDT) and the double-cantilever-beam (DCB) test provided a useful ranking of improvements in delamination resistance between brittle and tough resin composites. Several layups were designed for the edge delamination test to cover a wide range of mixed-mode conditions. The DCB and the various layups of the EDT were then used to characterize the interlaminar fracture behavior of brittle and toughened resin composites subjected to both static and cyclic loading.

Obrien, T. K.

1984-01-01

163

Improved microbial-check-valve resins  

NASA Technical Reports Server (NTRS)

Improved microbial-check-valve resins have been tested for their microbicidal effectiveness and long-term stability. Resins give more-stable iodine concentrations than previous preparations and do not impart objectionable odor or taste to treated water. Microbial check valve is small cylindrical device, packed with iodide-saturated resin, that is installed in water line where contamination by micro-organisms is to be prevented. Prototype microbial check valve was tested for stability and performance under harsh environmental conditions. Effectiveness was 100 percent at 35 deg, 70 deg, and 160 deg F (2 deg, 21 deg, and 71 deg C).

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

1980-01-01

164

Method for selective plugging using resin emulsions  

SciTech Connect

Methods and compositions are provided for selectively plugging the water-rich strata of subterranean formations, including injection into the formation of a water-insoluble, oil-soluble resin emulsion. A series of chemical reactions is initiated insitu such that the emulsion demulsifies, resulting in the coalescence of resin droplets. The coalesced water-insoluble, oil-soluble resin droplets are effective to selectively plug the water-rich strata over a relatively long distance and over a relatively long period of time.

Friedman, R.H.

1982-10-05

165

Chemical Characterization of Phenol/Formaldehyde Resins  

NASA Technical Reports Server (NTRS)

Report discusses tests of commercial phenol/formaldehyde resins to establish relationships among composition before use, behavior during curing, and strength after curing. Resin used in carbon/carbon laminates. In curing process, two molecules of phenol joined together in sequence of reactions involving molecule of formaldehyde. Last step of sequence, molecule of water released. Sequence repeats until one of ingredients used up, leaving solidified thermoset plastic. Issues to be resolved: number and relative abundances of ingredients, presence of certain chemical groups, heat-producing ability of resin, and range of molecular weights present.

Brayden, T. H.

1986-01-01

166

SEM and elemental analysis of composite resins  

SciTech Connect

Twenty-four chemically cured, 21 light-cured anterior, three light-cured anterior/posterior, and 18 light-cured posterior composite resins were examined using scanning electron microscopy, and the elemental composition of their filler particles was analyzed with an energy dispersive electron probe microanalyzer. According to the results obtained, the composite resins were divided into five groups (traditional, microfilled type, submicrofilled type, hybrid type, and semihybrid), with two additional hypothetical categories (microfilled and hybrid). Characteristics of each type were described with clinical indications for selective guidance of respective composite resins for clinical use.

Hosoda, H.; Yamada, T.; Inokoshi, S. (Tokyo Medical and Dental Univ., (Japan))

1990-12-01

167

Cobalt Ions Improve the Strength of Epoxy Resins  

NASA Technical Reports Server (NTRS)

Technique developed for improving mechanical strength of epoxy resins by adding cobalt ions in form of tris(acetylacetonato)cobalt (III) complex. Solid cast disks prepared from cobalt ion-containing epoxy resins tested for flexural strength and stiffness. Incorporation of cobalt ions into epoxies increased flexural strength of resins by 10 to 95 percent. Suitable resins for this technique include any liquid or solid TGMDA resins. Improved epoxy formulation proves useful as composite matrix resin, adhesive, or casting resin for applications on commercial and advanced aircraft.

Stoakley, D. M.; St. Clair, A. K.

1986-01-01

168

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

169

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

170

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

171

Phenoxy resins containing pendent ethynyl groups and cured resins obtained therefrom  

NASA Technical Reports Server (NTRS)

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

Hergenrother, P. M. (inventor)

1985-01-01

172

Synthesis of improved phenolic and polyester resins  

NASA Technical Reports Server (NTRS)

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

Delano, C. B.

1980-01-01

173

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2011 CFR

...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1...of this chapter and the following: (1) Benzoyl chloride, poly(tetrafluoro ethylene). (2) [Reserved] (c)...

2011-04-01

174

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2010 CFR

...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1...of this chapter and the following: (1) Benzoyl chloride, poly(tetrafluoro ethylene). (2) [Reserved] (c)...

2010-04-01

175

Determining resin/fiber content of laminates  

NASA Technical Reports Server (NTRS)

Article discusses procedure where hydrazine is used to extract graphite fibers from cured polyimide resin. Method does not attack graphite fibers and is faster than hot-concentrated-acid digestion process.

Garrard, G. G.; Houston, D. W.

1979-01-01

176

An update on resin-bonded bridges.  

PubMed

Since the introduction of the 'Rochette' bridge in the 1970s the resin-bonded bridge has undergone a number of developments to become a commonly used technique for replacement of a missing tooth, especially in a minimally restored dentition. One of the major advantages of the resin-bonded bridge is that it requires less tooth preparation than conventional bridgework, with some authorities advising no preparation at all. Some reports have suggested poor long-term success rates, however, if used in appropriate clinical situations, this treatment modality can be extremely successful. The aim of this paper is to review the literature relating to resin-bonded bridges and suggest recommendations for clinicalpractice concerning the provision of resin-bonded bridges. PMID:18468318

Barber, M W; Preston, A J

2008-03-01

177

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2010 CFR

...hydrocarbons obtainable from sulfate turpentine and meeting the following specifications: Drop-softening point of 118°-138 °C; iodine value less than 20. (b) Terpene resins consisting of polymers of beta-pinene and meeting the following...

2010-04-01

178

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

179

Improved high-temperature resistant matrix resins  

NASA Technical Reports Server (NTRS)

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

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

1989-01-01

180

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

181

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

182

77 FR 1267 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...  

Federal Register 2010, 2011, 2012, 2013, 2014

...defined here: ABS--Acrylonitrile Butadiene Styrene Resin ADAF...Resins Source Categories A. Acrylonitrile Butadiene Styrene Resin (ABS) B...Methacrylate- 325211 1317 Acrylonitrile-Butadiene-Styrene...

2012-01-09

183

Imide modified epoxy matrix resins  

NASA Technical Reports Server (NTRS)

The results of a program designed to develop tough imide modified epoxy resins cured by bisimide amine (BIA) hardeners are described. State-of-the-art epoxides MY720 and DER383 were used, and four bismide amines were evaluated. These were the BIA's derived from the 6F anhydride (4,4'-(hexafluoroisopropylidene) bis(phthalic anhydride) and the diamines 3,3'-diaminodiphynyl sulfone, 4,4'-oxygianiline, 4,4'-methylene dianiline, and 1,12-dodecane diamine. A key intermediate, designated 6F anhydride, is required for the synthesis of the bisimide amines. Reaction parameters to synthesize a precursor to the 6F anhydride (6FHC) in high yields were investigated. The catalyst trifluoromethane sulfonic acid was studied. Although small scale runs yielded the 6FHC in 50 percent yield, efforts to ranslate these results to a larger scale synthesis gave the 6FHC in only 9 percent yield. Results show that the concept of using bisimide amine as curing agents to improve the toughness properties of epoxies is valid.

Scola, D. A.

1984-01-01

184

Effect of elevated temperatures on the strength of cured resins and resin-based materials  

Microsoft Academic Search

Measurement of the loss of weight and ultimate compressive strength of phenol-formaldehyde resins under the influence of elevated temperatures has shown that during thermal degradation there is an abrupt transition from a first to a second and third structural stage with steadily increasing stabilization of the strength properties. Apart from the dependence on the heat treatment conditions, all the resins

E. B. Trostyanskaya; V. U. Novikov; Yu. N. Kazanskii

1966-01-01

185

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

NASA Astrophysics Data System (ADS)

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

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

2007-04-01

186

Anion-exchange resin-based desulfurization process  

SciTech Connect

The University of Tennessee Space Institute (UTSI) has a Department of Energy grant to further develop the Institute's anion-exchange resin-based flue gas, desulfurization concept. The developmental program proposed includes screening of commercially available resins to select three candidate resins for further study. These three resins will undergo a series of experiments designed to test the resins' performance under different process conditions (including the use of spent MHD seed material). The best of these resins will be used in optimizing the regeneration step and in testing the effects of performance enhancers. The process schematic developed from the results will be used to estimate the related economics.

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

1991-01-01

187

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

188

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

189

76 FR 3614 - Granular Polytetrafluoroethylene Resin From Japan: Final Results of Sunset Review and Revocation...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Granular Polytetrafluoroethylene Resin From Japan: Final Results of Sunset Review and Revocation...polytetrafluoroethylene resin (``PTFE resin'') from Japan. See Initiation of Five-Year (``Sunset...duty order on imports of PTFE resin from Japan. See Antidumping Duty Order;...

2011-01-20

190

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

Federal Register 2010, 2011, 2012, 2013, 2014

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

2011-07-18

191

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

Federal Register 2010, 2011, 2012, 2013, 2014

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

2011-03-09

192

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

193

Additive effects on the toughening of unsaturated polyester resins  

SciTech Connect

An elastomer additive, carboxy-terminated acrylonitrile-butadiene copolymer, was used for toughening in the free radical cross-linking copolymerization of unsaturated polyester (UP) resins. For molded parts, Charpy impact behavior was generally enhanced and the number of catastrophic failures was reduced. The miscibility and interfacial properties of additive and resin blends play important roles in the toughening process. Phase-diagram studies showed that the elastomer additive is immiscible with the UP resin and is phase-separated from the resin matrix during curing. This phase-separation phenomenon is similar to that in the low-profile mechanism of UP resins. Additive-resin system miscibility greatly influences curing morphology. Microvoids occurred in the additive phase of cured resin because of shrinkage stress. The intrinsic inhomogeneity of the polyester network and the existence of microvoids in the final product limit the toughening effect of additives on unsaturated polyester resins. 49 refs., 13 figs., 3 tabs.

Suspene, L. [Centre de Recherches et de Technologies de Verneuil, Verneuil-en-Halatte (France); Yang, Y.S.; Pascault, J.P. [Institut National des Science Appliquees de Lyon, Villeurbanne (France)

1993-12-31

194

Performance Properties of Graphite Reinforced Composites with Advanced Resin Matrices  

NASA Technical Reports Server (NTRS)

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

Kourtides, Demetrius A.

1980-01-01

195

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

Code of Federal Regulations, 2014 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2014-04-01

196

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

Code of Federal Regulations, 2013 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2013-04-01

197

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

Code of Federal Regulations, 2010 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2010-04-01

198

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

Code of Federal Regulations, 2012 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2012-04-01

199

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

Code of Federal Regulations, 2011 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2011-04-01

200

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 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....

2012-04-01

201

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 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....

2013-04-01

202

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 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....

2014-04-01

203

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2013 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2013-04-01

204

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2010 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2010-04-01

205

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2014 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2014-04-01

206

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2012 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2012-04-01

207

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2011 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2011-04-01

208

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a...

2011-04-01

209

21 CFR 872.3300 - Hydrophilic resin coating for dentures.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin...

2013-04-01

210

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a...

2014-04-01

211

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a...

2010-04-01

212

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a...

2013-04-01

213

21 CFR 872.3300 - Hydrophilic resin coating for dentures.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin...

2011-04-01

214

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2010 CFR

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

2010-04-01

215

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2011 CFR

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

2011-04-01

216

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2014 CFR

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

2014-04-01

217

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2012 CFR

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

2012-04-01

218

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

219

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

220

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2013 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2013-04-01

221

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2012 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2012-04-01

222

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2010 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2010-04-01

223

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2011 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2011-04-01

224

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2014 CFR

...HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2014-04-01

225

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

226

Technical assessment for quality control of resins  

NASA Technical Reports Server (NTRS)

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

Gosnell, R. B.

1977-01-01

227

Resin transfer molding of textile composites  

NASA Technical Reports Server (NTRS)

The design and manufacture of textile composite panels, tubes, and angle sections that were provided to NASA for testing and evaluation are documented. The textile preform designs and requirements were established by NASA in collaboration with Boeing and several vendors of textile reinforcements. The following four types of preform architectures were used: stitched uniweave, 2D-braids, 3D-braids, and interlock weaves. The preforms consisted primarily of Hercules AS4 carbon fiber; Shell RSL-1895 resin was introduced using a resin transfer molding process. All the finished parts were inspected using ultrasonics.

Falcone, Anthony; Dursch, Harry; Nelson, Karl; Avery, William

1993-01-01

228

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Polyester resin kits. 173.165 Section 173.165...Other Than Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Polyester resin kits consisting of a base material...

2013-10-01

229

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 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...

2012-10-01

230

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

231

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Polyester resin kits. 173.165 Section 173.165...Other Than Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Polyester resin kits consisting of a base material...

2014-10-01

232

Seasonal variation in the leaf resin components of Mimulus aurantiacus  

Microsoft Academic Search

The chaparral subshrub, Mimulus aurantiacus, produces leaf surface resins in excess of 30% of leaf dry weight. The resin provides some defense against the insect herbivore, Euphydryas chalcedona, and perhaps from desiccation and injury from UV light. The resin comprises six flavanones and an ?-pyrone. The different components may differ in their ecological roles. Methoxylated components may be most effective

J. Daniel Hare

2002-01-01

233

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

234

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

235

Urea–formaldehyde (UF) adhesive resins for wood  

Microsoft Academic Search

Urea–formaldehyde (UF) resins are the most important type of adhesive resins for the production of wood based panels. They convince by their high reactivity and good performance in the production and by their low price, however they lack in water resistance of the hardened resin owing to the reversibility of the aminomethylene link and hence the susceptibility to hydrolysis. This

M. Dunky

1998-01-01

236

Reactivity of Trametes laccases with fatty and resin acids  

Microsoft Academic Search

Lipophilic extractives commonly referred to as wood pitch or wood resin can have a negative impact on paper machine runnability and product quality. The lipophilic extractives are composed mainly of fatty acids, resin acids, sterols, steryl esters and triglycerides. In this work, the suitability of laccases for the modification of fatty and resin acids was studied, using two model fractions.

Stina Karlsson; Bjarne Holmbom; Peter Spetz; Annikka Mustranta; Johanna Buchert

2001-01-01

237

Occupational asthma due to unheated polyvinylchloride resin dust.  

PubMed Central

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

1989-01-01

238

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

NASA Technical Reports Server (NTRS)

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

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

2007-01-01

239

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

Microsoft Academic Search

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

Diane Martin; Dorothea Tholl; Jonathan Gershenzon; Jorg Bohlmann

2002-01-01

240

Fiber reinforced thermoplastic resin matrix composites  

NASA Technical Reports Server (NTRS)

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

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

1989-01-01

241

[Study of purity tests for silicone resins].  

PubMed

In the 8th edition of Japan's Specifications and Standards for Food Additives, the purity test for silicone resins requires the determination of the refractive index and kinetic viscosity of the extracted silicone oil, and allows for only a limited amount of silicon dioxide. In the purity test, carbon tetrachloride is used to separate the silicone oil and silicon dioxide. To exclude carbon tetrachloride, methods were developed for separating the silicone oil and silicon dioxide from silicone resin, which use hexane and 10% n-dodecylbenzenesulfonic acid in hexane. For silicone oil, the measured refractive index and kinetic viscosity of the silicone oil obtained from the hexane extract were shown to be equivalent to those of the intact silicone oil. In regard to silicon dioxide, it was confirmed that, following the separation with 10% n-dodecylbenzenesulfonic acid in hexane, the level of silicon dioxide in silicone resin can be accurately determined. Therefore, in this study, we developed a method for testing the purity of silicone resins without the use of carbon tetrachloride, which is a harmful reagent. PMID:23243991

Sato, Kyoko; Otsuki, Noriko; Ohori, Akio; Chinda, Mitsuru; Furusho, Noriko; Osako, Tsutomu; Akiyama, Hiroshi; Kawamura, Yoko

2012-01-01

242

Glutathione Resins I. List of Components  

E-print Network

that is applicable for up to 50 g of E. coli cells. Other extraction methods can be used with varying recovery purifications of up to 10 mg of GST-tagged protein per column. · Five Glutathione-Uniflow Columns Each column Clontech · www.clontech.com · 800-662-2566 #12;GlutathioneResinProtocol · Polypropylene tubes · Centrifuge

Lebendiker, Mario

243

REMOVING RADIUM-226 ION EXCHANGE RESINS  

E-print Network

1 1 REMOVING RADIUM-226 FROM ION EXCHANGE RESINS USED IN DRINKING WATER TREATMENT James McMahon Dr) SEPTEMBER 22, 2007 2 Presentation Outline · Radionuclide/Radium-226 Regulations · Radium-226 Treatment for Radionuclides · 1962 US Public Health Services DWS ­ 3 pCi/L Radium 226 · 1977 USEPA National Interim Prim. DWS

244

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

245

Antimicrobial activity of resin acid derivatives  

Microsoft Academic Search

The wide potential of resin acids as bioactive agents gave rise to a growing effort in the search for new applications of the natural forms and their derivatives. In some of these compounds, the antimicrobial activity is associated to the presence in the molecules of functional groups such as the hydroxyl, aldehyde, and ketone or to their cis or trans

Sonia Savluchinske-Feio; Maria João Marcelo Curto; Bárbara Gigante; J. Carlos Roseiro

2006-01-01

246

A model for resin viscosity during cure in the resin transfer moulding process  

Microsoft Academic Search

A cure model has been developed for the viscosity of two-part epoxy\\/amine resins, focussing on low extents of cure—the most important region for the mould-filling stage in resin transfer moulding. A key advantage of the model is that it is not explicitly dependent on the extent of cure; therefore, the model can be used to predict the viscosity during cure

N Kiuna; C. J Lawrence; Q. P. V Fontana; P. D Lee; T Selerland; P. D. M Spelt

2002-01-01

247

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

248

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

249

Stability Of A Carbon-Dioxide-Removing Resin  

NASA Technical Reports Server (NTRS)

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

Wydeven, Theodore; Wood, Peter

1990-01-01

250

ANALYSIS OF VENTING OF A RESIN SLURRY  

SciTech Connect

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

Laurinat, J.; Hensel, S.

2012-03-27

251

Analysis of chromite by cation-exchange using ethylenediaminetetra-acetic acid.  

PubMed

A method for the separation and determination of five major elements in chromite ore (and chrome-bearing refractories), based on complexation of the metals with EDTA is described. After removal of silica, the cations are separated into two groups by passing the solution through a cation-exchange resin (Dowex 50W-X8, in Na-form) in the presence of an excess of the complexing agent. The optimum conditions for the separation are discussed on the basis of exchange constants that were either known or determined. The first group contains Cr and Fe, which emerge in the filtrate at pH between 1.5 and 2.1, whereas A1, Mg and Ca, which are adsorbed on the resin, form another group. Complexometric titrations are used for the subsequent determination of the cations in each group. The method is simpler and more rapid and accurate for routine analysis than the current methods. PMID:18961783

Jawaid, M; Ingman, F

1975-12-01

252

Synthesis and Characterizations of Melamine-Based Epoxy Resins  

PubMed Central

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

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

2013-01-01

253

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

254

Effect of Resin Coating and Chlorhexidine on Microleakage of Two Resin Cements after Storage  

PubMed Central

Objective: Evaluating the effect of resin coating and chlorhexidine on microleakage of two resin cements after water storage. Materials and Methods: Standardized class V cavities were prepared on facial and lingual surfaces of one hundred twenty intact human molars with gingival margins placed 1 mm below the cemento-enamel junction. Indirect composite inlays were fabricated and the specimens were randomly assigned into 6 groups. In Groups 1 to 4, inlays were cemented with Panavia F2.0 cement. G1: according to the manufacturer’s instruction. G2: with light cured resin on the ED primer. G3: chlorhexidine application before priming. G4: with chlorhexidine application before priming and light cured resin on primer. G5: inlays were cemented with Nexus 2 resin cement. G6: chlorhexidine application after etching. Each group was divided into two subgroups based on the 24-hour and 6-month water storage time. After preparation for microleakage test, the teeth were sectioned and evaluated at both margins under a 20× stereomicroscope. Dye penetration was scored using 0–3 criteria. The data was analyzed using Kruskal-Wallis and complementary Dunn tests. Results: There was significantly less leakage in G2 and G4 than the Panavia F2.0 control group at gingival margins after 6 months (P<0.05). There was no significant differences in leakage between G1 and G3 at both margins after 24 hours and 6 months storage. After 6 months, G6 revealed significantly less leakage than G5 at gingival margins (P=0.033). In general, gingival margins showed more leakage than occlusal margins. Conclusion: Additionally, resin coating in self-etch (Panavia F2.0) and chlorhexidine application in etch-rinse (Nexus) resin cement reduced microleakage at gingival margins after storage. PMID:21998773

Shafie, F.; Doozandeh, M.; Alavi, A.

2010-01-01

255

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

256

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

257

Processable polyimide adhesive and matrix composite resin  

NASA Technical Reports Server (NTRS)

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

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

1990-01-01

258

Expandable Foam from Amorphous Polyester Resin  

Microsoft Academic Search

A resilient foam that is both expandable and moldable was prepared from an amorphous polyester resin using a mixed blowing agent of a high-solubility compound and a low-permeability compound. The high-solubility compound permits a high degree of expansion, while the low-permeability compound renders secondary expandability. The polyester foam remedies the deficiencies of existing bead products. Polystyrene beads retain blowing agents

Chung P. Park; Gerald A. Garcia; Roby G. Watson

2003-01-01

259

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

260

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

261

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

262

Copper resinate: an XPS study of degradation  

NASA Astrophysics Data System (ADS)

In this paper, we describe an X-ray photoelectron spectroscopy (XPS) study of copper resinate, a transparent green glaze that is coloured by copper salts of resin acids. This pigment was used in Europe in the fifteenth and sixteenth centuries, but it does not seem to be a usual feature of the palette anywhere after the end of the sixteenth century, because its tendency to discolour was already widely known by artists. An essential prerequisite for the restoration of works of art is the understanding of the effects of various climatic parameters on the deterioration process. For this reason, pictorial models of copper resinate in linseed oil, capable of simulating the ancient paintings on mobile supports, were prepared and aged in a climatic chamber, under different conditions such as exposure to UV radiations, humidity and different concentration of chemical pollutants (NO2 and SO2). All the samples were investigated by XPS and the data obtained were evaluated in order to estimate aging effects as well as mechanisms of degradation. On these paint layers damage induced by X-ray irradiation was also verified.

Altavilla, C.; Ciliberto, E.

2006-06-01

263

Composite fabrication via resin transfer molding technology  

SciTech Connect

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

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

1996-04-01

264

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

265

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

266

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

267

Health Problems of Epoxy Resins and Amine-curing Agents  

PubMed Central

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

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

1959-01-01

268

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

269

CCMR: Green Composites: Using Modified Sunflower Based Resins  

NSDL National Science Digital Library

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

Yarbrough, DeAnna S.

2010-08-15

270

Epoxy Resin\\/Graphite Electrically Conductive Nanosheet Nanocomposite  

Microsoft Academic Search

In this study, graphite nanosheets were prepared by powdering expanded graphite with sonication in aqueous alcoholic solution. Epoxy resin\\/graphite nanosheet nanocomposites were fabricated and their electrical and mechanical properties were investigated. The results revealed that graphite sheets 30–80 nm in thickness could be effectively dispersed within the epoxy resin. The percolation threshold of epoxy resin\\/graphite nanoparticles was about 0.015, much lower

Wei Lu; Jianxin Weng; Dajun Wu; Cuiling Wu; Guohua Chen

2006-01-01

271

Detection and Identification of Simple Phenolics in Pistacia lentiscus Resin  

Microsoft Academic Search

Identification and quantification of a series of phenolic compounds in Pistacia lentiscus resin, commonly known as Chios mastic gum, has been achieved based on high performance liquid chromatography (HPLC) fractionation of polar extract of the resin prior to dual?column gas chromatography?mass spectrometry (GC?MS) analysis. Polyphenols were extracted from the resin with methanol\\/water and the extract was fractionated by HPLC. Identification

A. C. Kaliora; A. Mylona; A. Chiou; D. G. Petsios; N. K. Andrikopoulos

2005-01-01

272

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

273

Detoxification of lignocellulose hydrolysates with ion-exchange resins  

Microsoft Academic Search

Lignocellulose hydrolysates contain fermentation inhibitors causing decreased ethanol production. The inhibitors include phenolic\\u000a compounds, furan aldehydes, and aliphatic acids. One of the most efficient methods for removing inhibiting compounds prior\\u000a to fermentation is treatment of the hydrolysate with ion-exchange resins. The performance and detoxification mechanism of\\u000a three different resins were examined: an anion exchanger, a cation exchanger, and a resin

Nils-Olof Nilvebrant; Anders Reimann; Simona Larsson; Leif J. Jönsson

2001-01-01

274

Phenol-Crotonaldehyde Resins. III. Curing Behavior with Hexamethylenetetramine  

Microsoft Academic Search

Solid thermoplastic resins were prepared by acid-catalyzed condensation of phenol and crotonaldehyde (both crude and distilled). The thermal and curing properties were compared with the conventional phenol-formaldehyde (PF) novolak resins. Phenol-crotonaldehyde (PC) resins were found to be thermoplastic even after curing with the crosslinking agent hexamethylenetetramine up to 160°C. This curing behavior was observed irrespective of the purity of the

R. N. Dongre; S. Ponrathnam; V. M. Nadkarni

1987-01-01

275

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

276

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. PMID:25436237

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

2014-01-01

277

Synthesis and thermal degradation studies of melamine formaldehyde resins.  

PubMed

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. PMID:25436237

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

2014-01-01

278

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

279

A tool for increasing the lifetime of chromatography resins  

PubMed Central

There is a steadily increasing demand for speed, cost efficiency and process understanding within biopharmaceutical process development. To match this, a high-throughput method for screening of cleaning-in-place (CIP) conditions for chromatography resins has been developed. The methodology includes fouling of MabSelect SuRe chromatography resin in 96-well filter plates, cleaning of the fouled resin by incubation in different CIP agents, and finally, analysis of the residual impurities on the resin after cleaning. This article describes the improvements that transformed the method from low throughput and significant manual interference to a totally automated method with high throughput and good reproducibility. PMID:21304272

Grönberg, Anna; Eriksson, Malin; Ersoy, Maria

2011-01-01

280

Maleimido substituted cyclotriphosphazene resins for fire and heat resistant composites  

NASA Technical Reports Server (NTRS)

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

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

1983-01-01

281

Synthesis, characterization and analytical application of a hydroxamic acid resin.  

PubMed

A chelating ion-exchange resin with hydroxamic acid functional groups was synthesized from styrene-maleic acid co-polymer cross-linked with divinylbenzene. A resin prepared from equimolar amounts of styrene and maleic anhydride with 0.75 mole% divinylbenzene gives the best sorption characteristics. The selectivity of the resin for metal ions is copper(II) > cobalt(II) > zinc(II) > nickel(II) > manganese(II) > chromium(III) > iron(III) > vanadium(V). Copper(II), chromium(III) and iron(III) in chromium plating baths can be separated by use of the resin and determined spectrophotometrically. PMID:18964984

Mendez, R; Pillai, V N

1990-06-01

282

Novel processing and cure of epoxy resin systems  

NASA Astrophysics Data System (ADS)

Thermoset resin based prepregs are typically fabricated into advanced composite parts using autoclave cures of up to twelve hours in duration. Prepregs based on high performance engineering thermoplastic resins have better shelf lives but are more difficult to handle and require very high (300 C) temperatures for fabrication. This paper describes the development of epoxy resin systems which offer the potential of extended shelf life while curing at relatively low temperatures. These systems offer the user reductions in autoclave usage of 75 percent (or greater) and display some of the sought after processing characteristics of a thermoplastic thermoset. In addition, neat resin characterization, rheology information, and cure conditions are described.

Breitigam, W. V.; Bauer, R. S.; May, Clayton

283

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

284

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

Code of Federal Regulations, 2012 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...

2012-04-01

285

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

Code of Federal Regulations, 2014 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...

2014-04-01

286

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

Code of Federal Regulations, 2013 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...

2013-04-01

287

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

288

77 FR 31875 - Certain Rubber Resins and Processes for Manufacturing Same; Notice of Receipt of Complaint...  

Federal Register 2010, 2011, 2012, 2013, 2014

...COMMISSION [Docket No. 2897] Certain Rubber Resins and Processes for Manufacturing...received a complaint entitled Certain Rubber Resins and Processes for Manufacturing...United States after importation of certain rubber resins and processes for...

2012-05-30

289

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

Code of Federal Regulations, 2010 CFR

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

2010-07-01

290

40 CFR Appendix B to Subpart Nnn... - Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride  

Code of Federal Regulations, 2010 CFR

...developed for water-soluble phenolic resins that have a relatively high...may also be suitable for other phenolic resins, especially those with a high...HCl b. Free formaldehyde in phenolic resins is present as...

2010-07-01

291

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

Federal Register 2010, 2011, 2012, 2013, 2014

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

2011-05-17

292

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

Federal Register 2010, 2011, 2012, 2013, 2014

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

2011-05-12

293

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

294

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

295

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

296

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

297

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

Code of Federal Regulations, 2010 CFR

...isopropyl-idene-diphenol-phosphite ester resins. 189.300 Section 189...isopropyl-idene-diphenol-phosphite ester resins. (a) Hydrogenated 4,4?-isopropylidene-diphenolphosphite ester resins are the condensation...

2010-04-01

298

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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

299

40 CFR 63.5731 - What standards must I meet for resin and gel coat mixing operations?  

Code of Federal Regulations, 2010 CFR

...must I meet for resin and gel coat mixing operations? 63.5731 Section... Standards for Resin and Gel Coat Mixing Operations § 63.5731 What standards must I meet for resin and gel coat mixing operations? (a) All resin...

2010-07-01

300

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

301

Evaluating resin-enamel bonds by microshear and microtensile bond strength tests: effects of composite resin  

PubMed Central

Objectives The aims of this study were to evaluate the effect of resin composite (Filtek Z250 and Filtek Flow Z350) and adhesive system [(Solobond Plus, Futurabond NR (VOCO) and Adper Single Bond (3M ESPE)] on the microtensile (µTBS) and microshear bond strength (µSBS) tests on enamel, and to correlate the bond strength means between them. Material and methods Thirty-six extracted human molars were sectioned to obtain two tooth halves: one for µTBS and the other one for µSBS. Adhesive systems and resin composites were applied to the enamel ground surfaces and light-cured. After storage (37ºC/24 h) specimens were stressed (0.5 mm/ min). Fracture modes were analyzed under scanning electron microscopy. The data were analyzed using two-way ANOVA and Tukey's test (?=0.05). Results The correlation between tests was estimated with Pearson's product-moment correlation statistics (? =0.05). For both tests only the main factor resin composite was statistically significant (p<0.05). The correlation test detected a positive (r=0.91) and significant (p=0.01) correlation between the tests. Conclusions The results were more influenced by the resin type than by the adhesives. Both microbond tests seem to be positive and linearly correlated and can therefore lead to similar conclusions. PMID:21308290

de ANDRADE, Andrea Mello; MOURA, Sandra Kiss; REIS, Alessandra; LOGUERCIO, Alessandro Dourado; GARCIA, Eugenio Jose; GRANDE, Rosa Helena Miranda

2010-01-01

302

Sugar Cane Bagasse Lignin in Resol-Type Resin: Alternative Application for Ligninphenol-Formaldehyde Resins  

Microsoft Academic Search

Lignin can be recovered from sugar cane bagasse, which is widely available in Brazil as a residue from sugar mills. Many reports can be found in the literature on the partial replacement of phenol by lignin in phenolic-type resins, but normally only their application as an adhesive is considered. This work is part of a study intended to look for

Rogério S. J. Piccolo; Fernando Santos; Elisabete Frollini

1997-01-01

303

Microshear bond strength of composite resins to enamel and porcelain substrates utilizing unfilled versus filled resins  

PubMed Central

Background: Failures such as marginal discoloration and composite chipping are still the problems of tooth-colored restorations on the substrate of enamel and porcelain, which some of these problems are consequently as a result of failures in the bonding layer. Using filled resin has been recently introduced to increase the bond strength of this layer. The aim of this study was to compare the microshear bond strength (?-SBS) of composite resins to enamel incubated in periods of 24 h and 9 months and porcelain with unfilled resin and flowable composites (filled resin). Materials and Methods: In this in vitro study, two groups of 75 enamel samples with different storage times (24 h and 9 months) and a group of 75 porcelain samples were used. They were divided into 5 experimental groups of 15 samples in each. Composite cylinders in tygon tubes were bonded on the surface of acid-etched enamel and pretreated porcelain. Wave, Wave MV, Wave HV, Grandioflow and Margin Bond were used as bonding agents. The ?-SBS was measured at the speed of 1.0 mm/min. The bond strengths were analyzed with one-way analysis of variance (ANOVA) test followed by Tukey test. P < 0.05 was selected as the level of statistical significance in this study. Results: The results showed that for enamel (24 h), the ?-SBS of the Wave MV and Wave HV groups were significantly lower than the Margin Bond group. Tukey test indicated the absence of a significant difference between the ?-SBS of the Wave group and the Margin Bond group. However, the ?-SBS of the Grandioflow group was significantly higher than the one for the Margin Bond as a bonding agent. In enamel (9 months), there was a significant difference between the Grandioflow and Margin Bond groups. Regarding bonding to the porcelain the one-way ANOVA test did not show a significant difference among the groups. Conclusion: This study revealed that flowable composites (filled resins) can be used instead of unfilled resins in bonding composite resins to enamel and porcelain substrates. PMID:25540657

Najafi-Abrandabadi, Ahmad; Najafi-Abrandabadi, Siamak; Ghasemi, Amir; Kotick, Philip G.

2014-01-01

304

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

305

Isothermal aging effects on PMR-15 resin  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

306

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

Code of Federal Regulations, 2012 CFR

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

2012-07-01

307

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

Code of Federal Regulations, 2014 CFR

...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

308

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

Code of Federal Regulations, 2013 CFR

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

2013-07-01

309

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

Code of Federal Regulations, 2011 CFR

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

2011-07-01

310

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

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Resorcinol, formaldehyde substituted carbomonocycle resin...Substances § 721.9480 Resorcinol, formaldehyde substituted carbomonocycle resin...identified generically as resorcinol, formaldehyde substituted carbomonocycle...

2012-07-01

311

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Resorcinol, formaldehyde substituted carbomonocycle resin...Substances § 721.9480 Resorcinol, formaldehyde substituted carbomonocycle resin...identified generically as resorcinol, formaldehyde substituted carbomonocycle...

2013-07-01

312

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

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Resorcinol, formaldehyde substituted carbomonocycle resin...Substances § 721.9480 Resorcinol, formaldehyde substituted carbomonocycle resin...identified generically as resorcinol, formaldehyde substituted carbomonocycle...

2011-07-01

313

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

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Resorcinol, formaldehyde substituted carbomonocycle resin...Substances § 721.9480 Resorcinol, formaldehyde substituted carbomonocycle resin...identified generically as resorcinol, formaldehyde substituted carbomonocycle...

2014-07-01

314

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

Code of Federal Regulations, 2010 CFR

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

2010-07-01

315

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

USGS Publications Warehouse

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

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

2009-01-01

316

A Comparison of Shear Bond Strength of Ceramic and Resin Denture Teeth on Different Acrylic Resin Bases  

PubMed Central

The purpose of this study is to compare the shear bond strength of different resin bases and artificial teeth made of ceramic or acrylic resin materials and whether tooth-base interface may be treated with aluminium oxide sandblasting. Experimental measurements were carried on 80 specimens consisting of a cylinder of acrylic resin into which a single tooth is inserted. An ad hoc metallic frame was realized to measure the shear bond strength at the tooth-base interface. A complete factorial plan was designed and a three-way ANalysis Of VAriance (ANOVA) was carried out to investigate if shear bond strength is affected by the following factors: (i) tooth material (ceramic or resin); (ii) base material (self-curing or thermal-curing resin); (iii) presence or absence of aluminium oxide sandblasting treatment at the tooth-base interface. Tukey post hoc test was also conducted to evaluate any statistically significant difference between shear strength values measured for the dif-ferently prepared samples. It was found from ANOVA that the above mentioned factors all affect shear strength. Furthermore, post hoc analysis indi-cated that there are statistically significant differences (p-value=0.000) between measured shear strength values for: (i) teeth made of ceramic material vs. teeth made of acrylic resin material; (ii) bases made of self-curing resin vs. thermal-curing resin; (iii) specimens treated with aluminium oxide sandblasting vs. untreated specimens. Shear strength values measured for acryl-ic resin teeth were on average 70% higher than those measured for ceramic teeth. The shear bond strength was maximized by preparing samples with thermal-curing resin bases and resin teeth submitted to aluminium oxide sandblasting. PMID:25614770

Corsalini, Massimo; Venere, Daniela Di; Pettini, Francesco; Stefanachi, Gianluca; Catapano, Santo; Boccaccio, Antonio; Lamberti, Luciano; Pappalettere, Carmine; Carossa, Stefano

2014-01-01

317

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

318

Space charge measurements on different epoxy resin-alumina nanocomposites  

Microsoft Academic Search

Recently a number of papers have reported enhanced electrical (ageing and breakdown) performance of nano-composites when compared to the properties of the base resin material. The physical reasons for this improvement are the subject of many current studies and have yet to be fully formulated. In this work, the build-up and decay of space charge in epoxy resin materials, containing

F. Magraner; A. Garci?a-Bernabe?; M. Gil; P. Llovera; S. J. Dodd; L. A. Dissado

2010-01-01

319

Guayule resin detection and influence on guayule rubber  

Technology Transfer Automated Retrieval System (TEKTRAN)

Guayule (Parthenium argentatum) is a natural rubber (cis-1,4-polyisoprene) producing crop, native to North America. Guayule also produces organic resins, complex mixtures of terpenes, triglycerides, guayulins, triterpenoids and other components. During natural rubber extraction, guayule resins can b...

320

Regional Measurement of Resin-Dentin Bonding as an Array  

Microsoft Academic Search

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

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

1999-01-01

321

The role of maleic anhydride in adhesive resin cements.  

PubMed

The adherence of resin cements depends upon, among other factors, the polar interactions across the interface: resin cement/restorative material. The polar interactions may be augmented by inclusion of polar additives such as maleic anhydride to the cement monomer. However, maleic anhydride is slowly converted to maleic acid when exposed to an aqueous environment. This may affect mechanical properties of such a cement in a negative way. It was the aim of the present investigation to analyze the role of maleic anhydride dissolved in the monomer of resin cements. The resin cement monomers used were common methacrylates, to which maleic anhydride in amounts of up to 30 mol% was added. Polymerization initiators were included to make the materials dual curing. Finally, the preparations were mixed with silanated fillers. The adherence energy of the cements bonded to a chromium-cobalt alloy was assessed by means of the double cantilever beam test. The strength and stiffness of the resin cements were recorded at base line and after two months storage in water. The initial adherence energy increased by a factor of about two as a result of addition of maleic anhydride. However, resin cements containing maleic anhydride suffered significant reductions in long-term adherence, strength and stiffness. These reductions were particularly pronounced in non-irradiated specimens. The use of resin cements containing maleic anhydride is not a viable means of conveying adhesiveness to resin cements. PMID:9708691

Asmussen, E; Peutzfeldt, A

1998-08-01

322

76 FR 4936 - Granular Polytetrafluoroethylene Resin From Italy  

Federal Register 2010, 2011, 2012, 2013, 2014

...identified a review on granular PTFE resin from Japan, it did not...review of the order on granular PTFE resin from Italy. Instead...cut-to-length carbon quality steel plate...antidumping duty orders on granular PTFE from Italy and Japan, and...

2011-01-27

323

Viscoelastic Properties of an Epoxy Resin during Cure  

E-print Network

Viscoelastic Properties of an Epoxy Resin during Cure DANIEL J. O'BRIEN1 Department of Mechanical of these issues with experimental and analytical viscoelastic characterization of an epoxy resin throughout the entire cure process. There has been limited work in the literature on the development of viscoelastic

Mather, Patrick T.

324

Retrospective study of orthodontic bonding without liquid resin  

Microsoft Academic Search

The aim of this study was to evaluate the retention of fixed orthodontic appliances bonded without liquid resin with the use of a retrospective study design. Patients from each of 2 consultant orthodontists in the same specialty clinic were chosen under strict selection criteria. In the test group (n = 37), composite material (Phase II) without liquid resin was used

Alexander T. H. Tang; Lars Björkman; Lars Isaksson; Karl-Fredrik Lindbäck; Anna Andlin-Sobocki; Jan Ekstrand

2000-01-01

325

Characterization of DGEBA (diglycidyl ethers bisphenol-A) epoxy resins  

SciTech Connect

High-resolution gel permeation chromatography and high-performance liquid chromatography can be applied to commercially available DGEBA epoxy resins to elucidate small but significant differences in the oligomer and impurity compositions of these resins. The GPC profiles can be used to type or identify the various commercial grades of these DGEBA resins. Lot-to-lot consistency and aging characteristics can also be determined using GPC and HPLC. Quantitation of the various oligomers and impurities such as the ..cap alpha..-glycol, isomer, and chlorohydrin species is possible. Using 20% isoconversion predictive cure thermal analysis data, the relative resin reactivity of several liquid, low-molecular DGEBA resins has been measured. These data show that the higher viscosity, higher oligomer content resins, which have higher hydroxyl content, reacted faster with amine cure agents than the lower viscosity, higher purity - and consequently lower hydroxyl content - resins. Thus, a combination of liquid chromatography (GPC or HPLC) and DSC kinetics can be used to establish a correlation or equivalency beween the commercially available low-molecular-weight DGEBA epoxy resins.

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

1987-04-01

326

SECURING CONTAINERIZED HAZARDOUS WASTES WITH POLYETHYLENE RESIN AND FIBERGLASS ENCAPSULATES  

EPA Science Inventory

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

327

Method and solvent composition for regenerating an ion exchange resin  

DOEpatents

A method and composition for removing perchlorate from a highly selective ion exchange resin is disclosed. The disclosed approach comprises treating the resin in a solution of super critical or liquid carbon dioxide and one or more quaternary ammonium chloride surfactant compounds.

Even, William R. (Livermore, CA); Irvin, David J. (Livermore, CA); Irvin, Jennifer A. (Livermore, CA); Tarver, Edward E. (Livermore, CA); Brown, Gilbert M. (Knoxville, TN); Wang, James C. F. (Livermore, CA)

2002-01-01

328

Team 1: Design of Carbon Fiber Resin Composites for Improved  

E-print Network

the transportation industry because of their incredible strength and very low weight. Unfortunately, these composites9999 #12;100 Team 1: Design of Carbon Fiber Resin Composites for Improved Fatigue Behavior Sponsored by: MSH1 Bicycle Works Sponsor Advisor: Matthew Klucha Design of Carbon Fiber Resin Composites

Alpay, S. Pamir

329

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

330

Antimicrobial activity of resin acid derivatives.  

PubMed

The wide potential of resin acids as bioactive agents gave rise to a growing effort in the search for new applications of the natural forms and their derivatives. In some of these compounds, the antimicrobial activity is associated to the presence in the molecules of functional groups such as the hydroxyl, aldehyde, and ketone or to their cis or trans configurations. The resin acid family covers a spectrum of antimicrobial activities against several microorganisms, from bacteria to fungi, in which the mode of action was studied by electron microscopy. The morphological alterations are consistent with an unspecific mode of action causing inhibition of the fungal growth or damaging the fungal cells in parallel with a mechanism of resistance based on the retention of the compound by the lipid accumulation. The sterol composition of phytopathogenic fungi Botrytis cinerea and Lophodermium seditiosum treated with methyl cis-7-oxo-deisopropyldehydroabietate revealed the presence of ergosterol (M+ 396) and dihydroergosterol (M+ 398) in both cultures showing that this compound did not interfere with the ergosterol metabolic pathway of both fungi. PMID:16896605

Savluchinske-Feio, Sonia; Curto, Maria João Marcelo; Gigante, Bárbara; Roseiro, J Carlos

2006-09-01

331

Radiation degradation in EPICOR-2 ion exchange resins  

SciTech Connect

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

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

1990-09-01

332

Surface characteristics of resin composite materials after finishing and polishing.  

PubMed

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

St Germain, Henry; Samuelson, Bart A

2015-01-01

333

Removal of perfluorooctane sulfonate from wastewater by anion exchange resins: effects of resin properties and solution chemistry.  

PubMed

Perfluorooctane sulfonate (PFOS) is a new persistent organic pollutant of substantial environmental concern, and its removal from industrial wastewater is critical to eliminate its release into water environment. In this paper, six anion exchange resins with different polymer matrix, porosity, and functional group were evaluated for PFOS removal from simulated wastewater. Resin matrix displayed significant effect on the sorption kinetics and capacity of PFOS, and the polyacrylic resins including IRA67 and IRA958 exhibited faster sorption and higher sorption capacity for PFOS than the polystyrene resins due to the hydrophilic matrix. Sorption isotherms illustrated that the sorption capacity of PFOS on IRA67 and IRA958 was up to 4-5 mmol/g, and the amount of PFOS sorbed on the resins was more than chloride released from resins, indicating that other interactions besides anion exchange were involved in the sorption. Solution pH had little impact on the sorption of PFOS on IRA958, but displayed significant effect on IRA67 at pH above 10 due to the deprotonation of amine groups. The coexisting sulfate and hexavalent chromium in wastewater interfered with the sorption of PFOS because of their competitive sorption on the exchange sites. The spent resins were successfully regenerated using the mixture of NaCl and methanol solution. This work provided an understanding of sorption behavior and mechanism of PFOS on different anion exchange resins, and should result in more effective applications of ion exchange for PFOS removal from industrial wastewater. PMID:20605036

Deng, Shubo; Yu, Qiang; Huang, Jun; Yu, Gang

2010-10-01

334

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

335

Adsorption behaviour of metal ions on hydroximate resins.  

PubMed

Some new chelating ion-exchange resins containing a hydroxamic acid moiety attached to a divinylbenzene styrene (DVBS) copolymer, i.e. glycine hydroximate in DVBS (GH-DVBS). anthranilic acid hydroximate in DVBS (AAHDVBS), malonic acid dihydroximate in DVBS (MAH-DVBS) and iminodiacetic acid dihydroximate in DVBS (IDAAH-DVBS). have been synthesized and their various physicochemical characteristics studied. The degree of retention of metal ions by the resins at equilibrium has been determined in terms of the molar distribution coefficient (k(d)). In general, the resins having a dihydroximate moiety are found to be more efficient compared to monohydroximate resins. However, it is of interest to note that the monohydroximate derivative of amino acid (GH-DVBS) showed better metal retention capability than the dihydroximate of carboxylic acid (MAH-DVBS). The selectivity of the resins for transition and highly charged metal ions is quite high compared to that for alkaline earth metals. All the synthesized resins can be utilized for the separation of a mixture of metal ions because the differences in the distribution coefficient values are large enough to permit good separations on columns. However, the GH-DVBS resin was tried for the separation of copper cobalt and copper nickel mixtures at pH 5.5 using the column mode of operation. PMID:18966686

Ahuja, M; Rai, A K; Mathur, P N

1996-11-01

336

Resin-Transfer-Molding of a Tool Face  

NASA Technical Reports Server (NTRS)

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

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

2004-01-01

337

Devices using resin wafers and applications thereof  

DOEpatents

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

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

2009-03-24

338

Critical appraisal. Resin bonding to zirconia.  

PubMed

Research has focused on adhesion and bond strengths to zirconia, but the question is "what is the gold standard--what is the bond strength we are trying to achieve?" Clinical data are needed to further understand adhesion issues--and studies are just now being published. Preliminary clinical research indicates that some failures are due to loss of adhesion but more are due to chipping of veneer porcelain. Commercial adhesion products are continuously being developed and optimized for clinical use. It is anticipated that the use of zirconia in dentistry will increase in the future, so reliable clinical adhesion solutions are needed. Based on the literature and the commercial products available to clinicians today, using novel primers (e.g., Z-PrimePlus) coupled with low pressure air-abrasion would be more than sufficient for adequate bonding of resin cement. PMID:23342396

Piascik, Jeffrey R

2012-12-01

339

Creep on a composite resin in water.  

PubMed

The compressive creep test of a composite resin (0-3.5 kg/mm2 stress levels) was conducted in water for 500 h. Linear regressions were obtained between the creep strains and the compressive stress levels at various hours. It is possible to predict the creep strain of the composite from the regression when it reaches water absorbed equilibrium after 500 h. The stress of the hygroscopic expansion was calculated from the linear regressions. The maximum stress due to the hygroscopic examination of the composite was 0.74 kg/mm2 at equilibrium of the water absorbed of the composite. The linear regressions at several compressive stress levels were obtained within 30-50 hr in the strain-log time diagrams. PMID:2638964

Hirano, S; Hirasawa, T

1989-06-01

340

Methane production using resin-wafer electrodeionization  

DOEpatents

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

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

2014-03-25

341

Transfer heat in a resin sheath  

SciTech Connect

As a material of construction for heat exchangers, fluoropolymers offer a combination of low cost and performance that is difficult for other materials to match. Durable, pliable, and less brittle than glass and graphite, fluoropolymers are generally specified over those materials in heat exchangers. Fluoropolymers have also displaced certain metals, depending on their susceptibility to corrosion from aggressive chemicals. Since making their debut in shell-and-tube models more than 30 years ago, fluoropolymers have also found their way into other configurations, namely reactor coils and immersion coils. Although fluoropolymer exchangers have proven their worth, there are still obstacles to overcome. One is the bias that exists toward process equipment that is made of plastic or other synthetic resins, particularly in high-heat environments. Secondly, there is the assumption that because fluoropolymers are inherently poor conductors of heat, they are odd candidates for heat exchangers. The paper discusses the advantages of fluoropolymer use in heat exchangers.

Wharry, S.R. Jr. [Ametek, Wilmington, DE (United States). Haveg Div.

1996-02-01

342

Geographic and genetic variation in the leaf surface resin components of Mimulus aurantiacus from southern California  

Microsoft Academic Search

Nearly 30% of the dry weight of leaves of the chaparral subshrub Mimulus aurantiacus comprise leaf surface resins. This resin provides some defense against the insect herbivore, Euphydryas chalcedona and may also protect plants from desiccation and UV light injury. The resin is composed of several components and the different components may contribute differentially to the resin's multiple protective roles.

J. D. Hare

2002-01-01

343

Study on the Miscibility of Chlorinated Polypropylene with Alkyd Resin by Dilute Solution Viscometry  

Microsoft Academic Search

The viscosity of dilute chlorinated polypropylene(CPP)-alkyd resin (344 resin)-toluene solutions at different compositions was measured, and the criteria, ?, ?k and ?, were calculated from the experimental data. The results obtained indicate that the miscibility of the 344 resin-CPP blends can be predicted by the criterion ?, and the blends are miscible when the weight percentage of 344 resin in

Zhong-Lei Fan; Da-Zhuang Liu; Jian-Ji Wang

2003-01-01

344

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

Microsoft Academic Search

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

Seong Jin Kim; Ho Jang

2000-01-01

345

Advanced thermoset resins for fire-resistant composites  

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

346

Chemical and biological investigation of Araucaria heterophylla Salisb. resin.  

PubMed

Three labdane diterpenes, namely lambda-8(17),14-diene, 13-epicupressic acid, and 13-Oacetyl-13-epicupressic acid, were isolated from the resin collected from stem exudates of Araucaria heterophylla Salisb. (Araucariaceae). The isolated compounds were identified using different spectroscopic methods (1H NMR, 13C NMR, HMQC, HMBC and COSY). The resin extract showed antiulcerogenic activity against ethanol-induced stomach ulcers in Sprauge Dawely rats using ranitidine as standard. In addition, the resin and the isolated compounds showed variable cytotoxic activities against breast (MCF7) and colon (HCT116) cancer cell lines. PMID:20158152

Abdel-Sattar, Essam; Monem, Azza R Abdel; Ezzat, Shahira M; El-Halawany, Ali M; Mouneir, Samar M

2009-01-01

347

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

348

Statistical failure analysis of adhesive resin cement bonded dental ceramics  

PubMed Central

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

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

2007-01-01

349

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

NASA Technical Reports Server (NTRS)

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

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

1991-01-01

350

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

NASA Technical Reports Server (NTRS)

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

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

1997-01-01

351

Continuous separation of carbohydrates by ion-exchange chromatography  

SciTech Connect

A synthetic mixture of fructose, mannitol and sorbitol was continuously separated by a chromatographic method using a cation-exchange resin (Dowex 50W-X8) in its Ca{sup 2+}-form as the stationary phase. An annular chromatograph (AC) was used to achieve a continuous mode of operation. Distribution and mass transfer coefficients of the three substances as well as bed properties were obtained by batch chromatography. The separation was simulated mathematically in terms of an approximate linear chromatographic theory was applied to the modeling of the behavior of the continuous separations. The influence of rotation rate, column loading, eluent flow rate and feed concentration on the resolution of the individual peaks were investigated.

Wolfgang, J.; Prior, A. [Prior Technology, Goetzis (Australia); Bart, H.J.; Messenboeck, R.C. [Univ. Kaiserslautern (Germany); Byers, C.H. [Oak Ridge National Lab., TN (United States)

1997-01-01

352

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

353

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

354

Metabolomics reveals the origins of antimicrobial plant resins collected by honey bees.  

PubMed

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

355

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

356

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

357

Matrix resin effects in composite delamination - Mode I fracture aspects  

NASA Technical Reports Server (NTRS)

A number of thermoset, toughened thermoset, and thermoplastic resin matrix systems were characterized for Mode I critical strain energy release rates, and their composites were tested for interlaminar critical strain energy release rates using the double cantilever beam method. A clear correlation is found between the two sets of data. With brittle resins, the interlaminar critical strain energy release rates are somewhat larger than the neat resin values due to a full transfer of the neat resin toughness to the composite and toughening mechanisms associated with crack growth. With tougher matrices, the higher critical strain energy release rates are only partially transferred to the composites, presumably because the fibers restrict the crack-tip deformation zones.

Hunston, Donald L.; Moulton, Richard J.; Johnston, Norman J.; Bascom, Willard D.

1987-01-01

358

Creep of an epoxy resin under transient temperatures  

E-print Network

(Member) . Saya Memb' r) August 1973 ABSTRACT Creep of an Epoxy Resin Under Transient Temperatures. (August 1973) Larry Alan Watkins, B. S. , Texas ASM Univers1ty D1rected by: Dr. R. A. Schapery Transient temperature tests were performed...

Watkins, Larry Alan

1973-01-01

359

A comparative study of fluoride-releasing adhesive resin materials.  

PubMed

One of the most important and exciting properties of recently introduced dental restorative materials is their ability to release fluoride ions, as this has several advantageous effects on tooth structures. They have been extensively used as fluoride-releasing filling and luting materials. Recently, fluoride-releasing adhesive resins and fluoride-releasing adhesive resin cement have been developed and introduced for clinical use. The purpose of this study was to evaluate the fluoride release from these adhesive resins and the fluoride uptake by both enamel and dentin, as well as the acid-resistance of these tooth structures. Based on our results, we conclude that fluoride-releasing adhesive resins and luting cements are useful for the prevention of initial or secondary caries, especially along the margins of restorations. PMID:12046524

Han, Linlin; Edward, Cruz; Okamoto, Akira; Iwaku, Masaaki

2002-03-01

360

Effects of Resin Hydrophilicity on Dentin Bond Strength  

PubMed Central

The purpose of this study was to determine if hydrophobic resins can be coaxed into dentin wet with ethanol instead of water. The test hypothesis was that dentin wet with ethanol would produce higher bond strengths for hydrophobic resins than would dentin wet with water. This study examined the microtensile bond strength of 5 experimental adhesives (50 wt% ethanol/50% comonomers) of various degrees of hydrophilicity to acid-etched dentin that was left moist with water, moist with ethanol, or air-dried. Following composite buildups, hourglass-shaped slabs were prepared from the bonded teeth for microtensile testing. For all 3 types of dentin surfaces, higher bond strengths were achieved with increased resin hydrophilicity. The lowest bond strengths were obtained on dried dentin, while the highest bond strengths were achieved when dentin was bonded moist with ethanol. Wet-bonding with ethanol achieved higher bond strengths with hydrophobic resins than were possible with water-saturated matrices. PMID:17062742

Nishitani, Y.; Yoshiyama, M.; Donnelly, A.M.; Agee, K.A.; Sword, J.; Tay, F.R.; Pashley, D.H.

2008-01-01

361

Cure of epoxy resins determined by simple tests  

NASA Technical Reports Server (NTRS)

Rapid visual and simple quantitative tests indicate the degree of cure of particular epoxy resin binders in prepreg stock. It is possible that these tests may be extended to a number of different epoxy formulations.

Ladaki, M.; Nigh, W. G.

1968-01-01

362

Photonic patterns printed in chiral nematic mesoporous resins.  

PubMed

Chiral nematic mesoporous phenol-formaldehyde resins, which were prepared using cellulose nanocrystals as a template, can be used as a substrate to produce latent photonic images. These resins undergo swelling, which changes their reflected color. By writing on the films with chemical inks, the density of methylol groups in the resin changes, subsequently affecting their degree of swelling and, consequently, their color. Writing on the films gives latent images that are revealed only upon swelling of the films. Using inkjet printing, it is possible to make higher resolution photonic patterns both as text and images that can be visualized by swelling and erased by drying. This novel approach to printing photonic patterns in resin films may be applied to anti-counterfeit tags, signage, and decorative applications. PMID:25682748

Khan, Mostofa K; Bsoul, Anas; Walus, Konrad; Hamad, Wadood Y; MacLachlan, Mark J

2015-03-27

363

Degradation, Fatigue, and Failure of Resin Dental Composite Materials  

SciTech Connect

The intent of this article is to review the numerous factors that affect the mechanical properties of particle- or fiber-filler-containing indirect dental resin composite materials. The focus will be on the effects of degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed-mode loading on flexure strength and fracture toughness. Several selected papers will be examined in detail with respect to mixed and cyclic loading, and 3D tomography with multi-axial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and/or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection); after that time period, failure most often results from secondary decay.

Drummond, J.L. (UIC)

2008-11-03

364

21 CFR 177.2260 - Filters, resin-bonded.  

Code of Federal Regulations, 2012 CFR

...together with adjuvant substances required in their preparation, application, and curing. (b) The quantity of any substance employed... List of Substances and Limitations (1) Fibers: Cellulose pulp. Cotton. Nylon. (From nylon resins...

2012-04-01

365

21 CFR 177.2260 - Filters, resin-bonded.  

Code of Federal Regulations, 2014 CFR

...together with adjuvant substances required in their preparation, application, and curing. (b) The quantity of any substance employed... List of Substances and Limitations (1) Fibers: Cellulose pulp. Cotton. Nylon. (From nylon resins...

2014-04-01

366

21 CFR 177.2260 - Filters, resin-bonded.  

Code of Federal Regulations, 2013 CFR

...together with adjuvant substances required in their preparation, application, and curing. (b) The quantity of any substance employed... List of Substances and Limitations (1) Fibers: Cellulose pulp. Cotton. Nylon. (From nylon resins...

2013-04-01

367

Effect of temperature on the flow properties of resin composite.  

PubMed

This study evaluated the effect of temperature on the flow characteristics of three different resin composites: a packable, a microhybrid, and a flowable. The film thickness of the three composites was measured at 21 degrees C, 41 degrees C, 61 degrees C, and 83 degrees C (+/- 1.0 degrees C). Five tests were performed for each resin composite at each of the four test temperatures for a total of 60 tests. The resin composite film thickness decreased as the filler percentage decreased and the temperature increased. The film thickness decrease was a logarithmic fit with a high correlation coefficient. All of the resin composites exhibited increased flow at elevated temperature. The flow property of the packable material at 41-61 degrees C was similar to that of the microhybrid at room temperature. PMID:16494114

Knight, James S; Fraughn, Robert; Norrington, David

2006-01-01

368

Shelf life determination of an epoxy resin by accelerated aging  

SciTech Connect

The objectives of the study reported were to first define the rate and mode of degradation of an epoxy resin at two storage conditions, 4.4/sup 0/C and 25/sup 0/C, by means of a thermally accelerated aging experiment. Then, samples which had been aged the equivalent of at least 10 years at each storage condition would be tested for conformance to the material specifications. The study's results demonstrate that the commercial resin could be acquired and stored for the required 10 to 11 years without concern over degradation. The expected changes at the two storage temperatures have been defined. Aged resin samples are shown to yield an acceptable product. Sufficient data exist to predict the changes in viscosity and epoxide equivalent of the resin at any other storage temperature of interest. (LEW)

Smith, H.M.

1983-11-01

369

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2011 CFR

...conditions: (a) Polysulfide polymer-polyepoxy resins are the reaction products of liquid polysulfide polymers and polyfunctional...Naphthalene sulfonic acid-formaldehyde condensate, sodium salt Sodium dibutyl naphthalene sulfonate Wetting agent....

2011-04-01

370

CHARACTERIZATION OF SORBENT RESINS FOR USE IN ENVIRONMENTAL SAMPLING  

EPA Science Inventory

The report describes the use of chromatographic techniques to characterize resins which are used to trap vapors in environmental sampling schemes. It describes two such techniques (frontal and elution analysis) which have been applied to characterize sorbent cartridges packed wit...

371

Elastomer-modified phosphorus-containing imide resins  

NASA Technical Reports Server (NTRS)

Phosphine oxide-containing polyimide resins modified by elastomers, are disclosed which have improved mechanical properties. These products are particularly useful in the production of fiber or fabric-reinforced composites or laminates.

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

1983-01-01

372

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

373

Definitive diagnostic waxing with light-cured composite resin.  

PubMed

The benefits of perceptive treatment planning for prosthodontics are discussed, and a method of developing diagnostic waxing with light-cured composite resin is described. The advantages of this programmed approach are illustrated with clinical examples. PMID:8229881

Tarantola, G J; Becker, I M

1993-10-01

374

Degradation, fatigue and failure of resin dental composite materials  

PubMed Central

The intent of this article is to review the numerous factors that affect the mechanical properties of particle or fiber filler containing, indirect dental resin composite materials. The focus will be on degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed mode loading on the flexure strength and fracture toughness. Next several selected papers will be examined in detail with respect to mixed and cyclic loading and then an examination of 3D tomography using multiaxial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection) and after that time period from secondary decay. PMID:18650540

Drummond, James L.

2008-01-01

375

21 CFR 177.2490 - Polyphenylene sulfide resins.  

Code of Federal Regulations, 2013 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...

2013-04-01

376

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

377

21 CFR 177.2490 - Polyphenylene sulfide resins.  

Code of Federal Regulations, 2012 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...

2012-04-01

378

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2012 CFR

...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

2012-04-01

379

21 CFR 177.2490 - Polyphenylene sulfide resins.  

Code of Federal Regulations, 2014 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...

2014-04-01

380

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2013 CFR

...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

2013-04-01

381

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2014 CFR

...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

2014-04-01

382

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2011 CFR

...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

2011-04-01

383

21 CFR 177.2490 - Polyphenylene sulfide resins.  

Code of Federal Regulations, 2010 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...

2010-04-01

384

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2010 CFR

...fluoride) basic resins have an intrinsic viscosity of not less than 0.75 deciliter per...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers...Standard Test Method for Dilute Solution Viscosity of Vinyl Chloride Polymers,”...

2010-04-01

385

Ultrasonic extraction of resins from an historic textile.  

PubMed

Ultrasound assisted extraction was applied on the historical textile as the most appropriate sample preparation step for the identification of the resinous binder. Fragile silk banner from the 19th century was analyzed for the presence of different resins. After the ultrasonic extraction with ethyl acetate in the ultrasonic bath, resinous materials and unknown sample from the banner were separated by thin layer chromatography. The multiple developments in benzene-methanol (95:5) system as mobile phase and silica gel layer as stationary phase were applied, and afterwards the video densitometry determination of the components was performed by means of video camera HV-C20. The shellac resin was determined as an important part of the complex binder. PMID:17822938

Rezi?, I; Krsti?, D; Boki?, Lj

2008-01-01

386

21 CFR 173.5 - Acrylate-acrylamide resins.  

Code of Federal Regulations, 2012 CFR

...polymer being composed of acrylamide units. (2) Sodium polyacrylate-acrylamide resin is produced by...and subsequent hydrolysis of acrylonitrile in a sodium silicate-sodium hydroxide aqueous solution, with the greater part of...

2012-04-01

387

21 CFR 173.5 - Acrylate-acrylamide resins.  

Code of Federal Regulations, 2013 CFR

...polymer being composed of acrylamide units. (2) Sodium polyacrylate-acrylamide resin is produced by...and subsequent hydrolysis of acrylonitrile in a sodium silicate-sodium hydroxide aqueous solution, with the greater part of...

2013-04-01

388

Assessment of arsenate bioavailability in iron-rich environments: development of a high-pressure liquid chromatography method of quanitification for arsenate sorbed by Fe3+-substituted chelating resins in arsenic-bearing ferrihydrite suspensions  

E-print Network

Given that the mobility, bioavailability, and toxicity of arsenate in natural systems is often controlled by the strong binding capacity of iron oxyhydroxides, the objective of this study was to document the interactions of Dowex M4195 Fe3...

Roberts, Melissa Delane

2005-08-29

389

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

390

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

391

WETTING BEHAVIORS OF PHENOL AND UREAFORMALDEHYDE RESINS AS COMPATIBILIZERS1  

Microsoft Academic Search

Understanding wetting behavior and surface coverage of resins on a wood surface is important to obtain satisfactory adhesion and optimize adhesive application for wood composite manufacturing. Sessile and micro-droplets of urea- and phenol-formaldehyde (UF and PF) resins were generated on wood surfaces to observe wetting behaviors using three directional image generation system and atomic force microscopy (AFM). The generated micro-droplet

Sangyeob Lee; Todd F. Shupe; Leslie H. Groom

392

Physical properties of epoxy resin\\/titanium dioxide nanocomposites  

Microsoft Academic Search

A polymeric nanocomposite system (nanodielectric) was fabricated, and its mechanical properties were determined. The fabricated nanocomposite was composed of low concentrations of monodispersed titanium dioxide (TiO) nanoparticles and an epoxy resin specially designed for cryogenic applications. The monodispersed TiO nanoparticles were synthesized in an aqueous solution of titanium chloride and polyethylene glycol and subsequently dispersed in a commercial-grade epoxy resin

Georgios Polyzos; Enis Tuncer; Isidor Sauers; Karren Leslie More

2011-01-01

393

Photoelastic Study of Epoxy Resin\\/Graphite Fiber Load Transfer  

Microsoft Academic Search

The physical techniques of polarising microscopy, including the measurement of small (<0.1?) optical retardations, have been used to investigate elastic fields adjacent to short (1-3 mm length) graphite fibers in epoxy resin composites. In as-cured specimens, i.e., in specimens self-stressed on account of resin cure shrinkage, the elastic field in the neighbourhood of fiber ends is, for surface treated fibers,

K. H. G. Ashbee; Elizabeth Ashbee

1988-01-01

394

Benzoxazine resin/carbon nanotube nanostructured composite's degradation kinetic.  

PubMed

In the last decades a new class of thermoset phenolic resin is emerging as a substitute of the traditional epoxy and phenolic resins in the aircraft industry. This new class is called polybenzoxazines and its associates the epoxy resin's mechanical properties and phenolic resin's thermal and flame retardant properties, resulting in a resin with superior properties when analyzed with the others singly. The introduction of carbon nanotubes in low concentration into polymeric matrices can produce nanostructured materials with good properties. Thus, in this study, nanostructured composites of benzoxazine resin were processed with different concentration of carbon nanotubes (0.1%, 0.5% and 1.0% w/w). In order to evaluate the thermostability of the benzoxazine resin and its nanostructured composites, it was performed a degradation kinetic study using the thermogravimetric technique. For that, the analysis have been done with the temperature ranging from 25 degrees C to 1000 degrees C at nitrogen atmosphere (100 mL x min(-1)) and in different heating rates (2, 4, 6, 8, 10 and 20 degrees C x min(-1)), in order to obtain the kinetic parameters (activation energy, E(a), and pre-exponential factor, A), based on Ozawa-Wall-Flynn model. The results showed excellent agreement between the thermogravimetric curves obtained and the Ozawa-Wall-Flynn method. The degradation kinetic study showed that the introduction of carbon nanotubes in the benzoxazine matrix does not change the thermostability of the resin, so that it does not have a significant influence in the shelf life of the material. PMID:24757993

Untem, Flávia O; Botelho, Edson C; Rezende, Mirabel C; Costa, Michelle Leali

2014-07-01

395

The clinical performance of cantilevered resin-bonded bridgework  

Microsoft Academic Search

Objectives: The technique of resin-bonded bridgework is a well-accepted clinical technique to replace missing teeth. This study assesses the clinical performance of cantilevered resin-bonded bridgework provided in a university teaching hospital environment.Methods: One-hundred and twelve patients who had a total of 142 cantilevered bridges were either examined or completed a questionnaire regarding their bridgework. The following data were recorded for

D. L. Hussey; G. J. Linden

1996-01-01

396

Rotational viscometry for the study of urea-formaldehyde resins  

Microsoft Academic Search

Rotational viscometry as a generally recognized method for rheological measurements of non-Newtonian liquids was used for the study of commercial urea-formaldehyde resins. The measurement results were analysed using the power law function with evaluation of the consistency and flow indices. The resins were observed during their storage until alkali-promoted poly- condensation led to gelation. It is suitable to differentiate two

Aime Suurpere; Peep Christjanson; Kadri Siimer

397

Static and cyclic loading of fiber-reinforced dental resin  

Microsoft Academic Search

Objective: The aim of this study was to evaluate the flexure strength of unidirectional fiber-reinforced resins under static and cyclic loading with and without thermal cycling.Methods: The fiber-reinforced resin materials chosen for this project were commercially available endodontic posts and commercially procured bar samples. For all materials, controls for flexure strength were tested in air and in water using three-point

James L Drummond; Mahendra S Bapna

2003-01-01

398

Separation of organic ion exchange resins from sludge -- engineering study  

SciTech Connect

This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

Duncan, J.B.

1998-08-25

399

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

400

Structure—property behaviour of gamma irradiated phosphinic acid resins  

Microsoft Academic Search

The effect of high dose (1000–6000 kGy) gamma radiation on the chemical and physical properties of the ionic polymer phosphinic acid resin has been investigated. It was found that the resin irradiated to a dose of 1000 kGy shows a decrease in the acid capacity of about 8%, reaching 25% at 6000 kGy. In addition, the grain size of the

A. M. El-Naggar; A. S. Emara; S. G. Abd Alla

1997-01-01

401

Preirradiation grafting of ethylene vinyl acetate copolymer resins  

Microsoft Academic Search

Acrylic acid was graft copolymerised on to EVA powdered resins containing 9%, 18% and 28% vinyl acetate. A preirradiation grafting method was used and the effect on graft level of varying the parameters of gamma irradiation dose (2–50 kGy), dose rate (0.5–5 kGy h?1), monomer concentration (2.5–25%) and grafting time (1–4 h) and temperature (35–98°C) was investigated. The graft copolymer resins

B. J Ringrose; E Kronfli

1999-01-01

402

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

403

A titanium and visible light-polymerized resin obturator.  

PubMed

Obturator prostheses are typically large, and their weight and size are often important design factors. This article describes the fabrication of an obturator prosthesis with a titanium framework and visible light-polymerized denture base resin. It is speculated that these low-density materials may produce prostheses lighter than similar ones made with conventional materials. An added advantage is that visible light-polymerizing resins facilitate relining. PMID:12011852

Rilo, Benito; da Silva, José Luis; Martinez-Insua, Arturo; Santana, Urbano

2002-04-01

404

Boron Isotope Fractionation in Column Chromatography with Glucamine Type Resins  

Microsoft Academic Search

Glucamine type resins have specific affinity toward boric acid and borate ion. Various studies of chromatographic separation of boron isotopes have been carried out, but few have addressed effects of base polymer skeletons. In this study, we used three glucamine type resins, which have different base polymer skeletons: synthesized GMA-DVB-Glu, commercial Diaion CRB02 and Chelest Fiber GRY-L. They were packed

Akinari SONODA; Yoji MAKITA; Takahiro HIROTSU

2006-01-01

405

CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN  

Microsoft Academic Search

This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two 11 mL beds in

C. Nash; M. Duignan

2010-01-01

406

Phenolformaldehyde resin curing and bonding under dynamic conditions  

Microsoft Academic Search

To better understand the curing and bonding behavior of phenol-formaldehyde (PF) resin under dynamic conditions, flakeboards were manufactured either by conventional pressing at 7% or 12% mat moisture content or by steam injection pressing with 10 or 20 seconds steaming duration. Resin-impregnated glass-cloth samples and lap-shear tension specimens were embedded in the core of each flakeboard. After the flakeboards were

Xiang-Ming Wang; Bernard Riedl; Robert L. Geimer; Alfred W. Christiansen

1996-01-01

407

Barium titanate formation by organic resins formed with mixed citrate  

Microsoft Academic Search

Citric precursors are used to produce BaTiO3, the Ba\\/Ti ratio being fixed by a mixed Ba-Ti citrate. The conditions for its solubility in organic agents (ethylene glycol or ethylene glycol+ citric acid) has been studied and used to investigate various routes of synthesis (resin, spray pyrolysis or films). The transformation from the resin to the mineral phase has been investigated.

J. P. Coutures; P. Odier; C. Proust

1992-01-01

408

Emission modeling of styrene from vinyl ester resins  

Microsoft Academic Search

The use of vinyl ester (VE) resins in the composites industry has increased in the last decade, and the trend is projected\\u000a to continue. Styrene is a commonly used co-monomer in VE resins, which acts as a reactive diluent and is required in many\\u000a liquid molding methods to reduce viscosity and increase gel time. The emission rate of styrene from

John J. La Scala; Chad A. Ulven; Joshua A. Orlicki; Rahul Jain; Giuseppe R. Palmese; Uday K. Vaidya; James M. Sands

2007-01-01

409

SuperLig Ion Exchange Resin Swelling and Buoyancy Study  

SciTech Connect

The objective of this study was to achieve a fundamental understanding of SuperLig resin swelling and shrinking characteristics, which lead to channeling and early breakthrough during loading cycles. The density of salt solution that causes resin floating was also determined to establish a limit for operation. Specific tests performed include (a) pH dependence, (b) ionic strength dependence and (c) buoyancy effect vs. simulant composition.

Hassan, N.M.

2000-07-27

410

Deacidification of a synthetic oil with an anion exchange resin  

Microsoft Academic Search

Esters of trimethylolpropane were prepared by reaction of trimethylolpropane with erucic acid. Unreacted erucic acid was eliminated\\u000a by fixation on an anion exchange resin to produce an oil with a low free fatty acid content. The authors describe the deacidification\\u000a of the reaction product by Lewatit MP500A and MP600 resins in a fixed-bed reactor or in a stirred reactor. The

Valérie Eychenne; Zéphirin Mouloungui

1998-01-01

411

Characterization and Process Development of Cyanate Ester Resin and Composite  

SciTech Connect

Cyanate ester (or polycyanate) resins offer advantages as composite matrices because of their high thermal stability, low outgassing, low water absorption and radiation resistance. This report describes the results of a processing study to develop high-strength hoop-wound composite by the wet-filament winding method using Toray T1000G carbon fiber and YLA RS-14A polycyanate resin as the constituent materials. Process trials, tests and analyses were conducted in order to gain insight into factors that can affect final properties of the cured cyanate ester resin and its composites. The study shows that the cyanate ester resin has a broad process envelope but that an inert-atmosphere cure is essential for obtaining optimum resin and composite properties. Minimizing moisture exposure prior to cure is also crucial as it affects the T{sub g} of the resin and composite. Recommendations for reducing moisture contact with the resin during wet-winding are presented. High fiber volume fraction ({approximately}80%) composites wound and cured with these methods yielded excellent hoop tensile strengths (660 to 670 ksi average with individual rings failing above 700 ksi), which are believed to be the highest recorded strengths for this class of materials. The measured transverse properties were also exceptional for these high fiber fraction composites. Based on the available data, this cyanate ester resin system and its composites are recommended for space and vacuum applications only. Further testing is required before these materials can be recommended for long term use at elevated temperatures in an ambient air environment. The results of all analyses and tests performed as part of this study are presented as well as baseline process for fabricating thick, stage-cured composites. The manufacture of a 1 in. thick composite cylinder made with this process is also described.

Frame, B.J.

1998-03-01

412

Preparation of high purity biphenyl cyclooctene lignans from Schisandra extract by ion exchange resin catalytic transformation combined with macroporous resin separation  

Microsoft Academic Search

In this study, ester-bond biphenyl cyclooctene lignans were efficiently hydrolytically degraded into free biphenyl cyclooctene lignans by ion exchange resin transformation and simultaneous removal of impurities by macroporous resin. The OH-type strongly basic anion exchange resin 201×7 was the best one, and the dynamic hydrolysis efficiency was 146.7±5.0%. HPD5000 macroporous resin, which offered higher adsorption and desorption capacities and faster

Chun-hui Ma; Ting-ting Liu; Lei Yang; Yuan-gang Zu; Feng-jian Yang; Chun-jian Zhao; Lin Zhang; Zhong-hua Zhang

2011-01-01

413

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

414

Gamma radiation effect on gas production in anion exchange resins  

NASA Astrophysics Data System (ADS)

Radiation-induced decomposition of Amberlite IRA400 anion exchange resin in hydroxide form by gamma radiolysis has been studied at various doses in different atmospheres (anaerobic, anaerobic with liquid water, and aerobic). The effect of these parameters on the degradation of ion exchange resins is rarely investigated in the literature. We focused on the radiolysis gases produced by resin degradation. When the resin was irradiated under anaerobic conditions with liquid water, the liquid phase over the resin was also analyzed to identify any possible water-soluble products released by degradation of the resin. The main products released are trimethylamine (TMA), molecular hydrogen (H2g) and carbon dioxide (CO2g). TMA and H2g are produced in all the irradiation atmospheres. However, TMA was in gaseous form under anaerobic and aerobic conditions and in aqueous form in presence of liquid water. In the latter conditions, TMAaq was associated with aqueous dimethylamine (DMAaq), monomethylamine (MMAaq) and ammonia (NH). CO2g is formed in the presence of oxygen due to oxidation of organic compounds present in the system, in particular the degradation products such as TMAg.

Traboulsi, A.; Labed, V.; Dauvois, V.; Dupuy, N.; Rebufa, C.

2013-10-01

415

A novel prosthetic resin composite containing fine enamel particles.  

PubMed

Finely powdered enamel was used to develop a prosthetic resin composite that has good mechanical properties and no potential to abrade opposing tooth structure. Bovine teeth were ground into powder and then the enamel particles were separated from the powder by centrifugation in bromoform-ethanol solution. The resin matrix consisted of UDMA (60 mole %) and Tri-EDMA (40 mole %). Camphorquinone (0.5 mass %) was added to the monomer as a photo-initiator. Fillers were incorporated directly into the resin matrix in amounts of 80 or 85 mass %. The flexural strength and Vickers hardness (Hv) were measured. The average flexural strength and Hv values for specimens having 85 mass % filler that had been subjected to heat treatment at 100 degrees C after light-curing were 95.2 and 109.8 MPa, respectively, which are higher than those for most commercial prosthetic resin composites. These findings suggest that a novel prosthetic resin composite with good mechanical properties can be made by loading finely powdered enamel into the resin matrix. PMID:19581711

Endo, Kazuhiko; Ohno, Hiroki

2009-01-01

416

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

417

Mechanical Properties of Degraded PMR-15 Resin  

NASA Technical Reports Server (NTRS)

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

Tsuji, Luis C.

2000-01-01

418

Methyl Jasmonate Induces Traumatic Resin Ducts, Terpenoid Resin Biosynthesis, and Terpenoid Accumulation in Developing Xylem of Norway Spruce Stems1  

PubMed Central

Norway spruce (Picea abies L. Karst) produces an oleoresin characterized by a diverse array of terpenoids, monoterpenoids, sesquiterpenoids, and diterpene resin acids that can protect conifers against potential herbivores and pathogens. Oleoresin accumulates constitutively in resin ducts in the cortex and phloem (bark) of Norway spruce stems. De novo formation of traumatic resin ducts (TDs) is observed in the developing secondary xylem (wood) after insect attack, fungal elicitation, and mechanical wounding. Here, we characterize the methyl jasmonate-induced formation of TDs in Norway spruce by microscopy, chemical analyses of resin composition, and assays of terpenoid biosynthetic enzymes. The response involves tissue-specific differentiation of TDs, terpenoid accumulation, and induction of enzyme activities of both prenyltransferases and terpene synthases in the developing xylem, a tissue that constitutively lacks axial resin ducts in spruce. The induction of a complex defense response in Norway spruce by methyl jasmonate application provides new avenues to evaluate the role of resin defenses for protection of conifers against destructive pests such as white pine weevils (Pissodes strobi), bark beetles (Coleoptera, Scolytidae), and insect-associated tree pathogens. PMID:12114556

Martin, Diane; Tholl, Dorothea; Gershenzon, Jonathan; Bohlmann, Jörg

2002-01-01

419

Apparatus and method for removing solvent from carbon dioxide in resin recycling system  

DOEpatents

A two-step resin recycling system and method solvent that produces essentially contaminant-free synthetic resin material. The system and method includes one or more solvent wash vessels to expose resin particles to a solvent, the solvent contacting the resin particles in the one or more solvent wash vessels to substantially remove contaminants on the resin particles. A separator is provided to separate the solvent from the resin particles after removal from the one or more solvent wash vessels. The resin particles are next exposed to carbon dioxide in a closed loop carbon dioxide system. The closed loop system includes a carbon dioxide vessel where the carbon dioxide is exposed to the resin, substantially removing any residual solvent remaining on the resin particles after separation. A separation vessel is also provided to separate the solvent from the solvent laden carbon dioxide. Both the carbon dioxide and the solvent are reused after separation in the separation vessel.

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

2009-01-06

420

Colour Stability of Heat and Cold Cure Acrylic Resins  

PubMed Central

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

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

2015-01-01

421

K Basin sludge/resin bead separation test report  

SciTech Connect

The K Basin sludge is an accumulation of fuel element corrosion products, organic and inorganic ion exchange materials, canister gasket materials, iron and aluminum corrosion products, sand, dirt and minor amounts of other organic material. The sludge will be collected and treated for storage and eventual disposal. This process will remove the large solid materials by a 1/4 inch screen. The screened material will be subjected to nitric acid in a chemical treatment process. The organic ion exchange resin beads produce undesirable chemical reactions with the nitric acid. The resin beads must be removed from the bulk material and treated by another process. An effective bead separation method must extract 95% of the resin bead mass without entraining more than 5% of the other sludge component mass. The test plan I-INF-2729, ``Organic Ion Exchange Resin Separation Methods Evaluation,`` proposed the evaluation of air lift, hydro cyclone, agitated slurry and elutriation resin bead separation methods. This follows the testing strategy outlined in section 4.1 of BNF-2574, ``Testing Strategy to Support the Development of K Basins Sludge Treatment Process``. Engineering study BNF-3128, ``Separation of Organic Ion Exchange Resins from Sludge,`` Rev. 0, focused the evaluation tests on a method that removed the fine sludge particles by a sieve and then extracted the beads by means of a elutriation column. Ninety-nine percent of the resin beads are larger than 125 microns and 98.5 percent are 300 microns and larger. Particles smaller than 125 microns make up the largest portion of sludge in the K Basins. Eliminating a large part of the sludge`s non-bead component will reduce the quantity that is lifted with the resin beads in the elutriation column. Resin bead particle size distribution measurements are given in Appendix A The Engineering Testing Laboratory conducted measurements of a elutriation column`s ability to extract resin beads from a sieved, non-radioactive sludge simulant. A elutriation column uses a constant velocity upward flow stream to segregate materials. In simplistic terms, the dense particles fall to the column`s bottom while the flow lifts less dense particles to the column`s top. A particle can be streamlined or have a high drag profile; this factor also influences the lift or fall of a particle exposed to the column flow. The sludge components that lift or fall are determined by the fluid velocity. The column flow velocity needed to lift the bulk of the resin beads will also lift other, non-bead, sludge components. Resin bead treatment and disposal are complicated by large quantities of non-bead material. Tests are necessary to determine a column flow velocity that will collect the bulk of the resin beads and the amount of non-bead sludge components that are also collected.

Squier, D.M.

1998-08-25

422

40 CFR Appendix A to Subpart Ddd... - Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method  

Code of Federal Regulations, 2010 CFR

...developed for water-soluble phenolic resins that have a relatively high...may also be suitable for other phenolic resins, especially those with a high...HCl b. Free formaldehyde in phenolic resins is present as...

2010-07-01

423

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

Code of Federal Regulations, 2010 CFR

...resin and gel coat application equipment cleaning standards? 63.5737 Section 63...Resin and Gel Coat Application Equipment Cleaning Operations § 63.5737 How do I...resin and gel coat application equipment cleaning standards? (a) Determine and...

2010-07-01

424

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

Code of Federal Regulations, 2010 CFR

...resin and gel coat application equipment cleaning operations? 63.5734 Section 63...Resin and Gel Coat Application Equipment Cleaning Operations § 63.5734 What standards...resin and gel coat application equipment cleaning operations? (a) For routine...

2010-07-01

425

Thermal removal of composite resin: effect on rebonding etched metal.  

PubMed

If a correctly etched-metal, resin-bonded fixed partial denture debonds, one recommendation for reuse is to clean the prosthesis by oven burnout, then to recement it without reetching. The purpose of this study was to determine whether the tensile strength of the bond of composite resin cement to either electrolytically or chemically etched metal was affected by earlier removal of residual resin with a burnout procedure. Pairs of rods made of nickel-chromium-beryllium were electrolytically or chemically etched according to accepted techniques, then bonded end-to-end with an enamel bonding agent and composite resin cement in an alignment apparatus. The rods were stored for 24 hours in 37 degrees C water, then debonded to determine the tensile bond strengths in megapascals. After debonding, the rods were placed in the burnout oven at 510 degrees C for 30 minutes. The rods were then ultrasonically cleaned in ethyl alcohol for 6 minutes. The pairs were rinsed under running water and then rebonded and debonded nine more times under the same conditions. A linear regression analysis revealed that there was no statistically significant difference (p less than 0.05) in the tensile strength of the bonds after repeated thermal cleanings and bondings. Correctly etched metal, resin-bonded fixed partial dentures may be recemented without re-etching after thermal cleaning without a statistically significant loss in the tensile strength of the bonds. PMID:2407826

Haywood, V B; Kanoy, B E; Bruggers, K J; Andreaus, S B

1990-03-01

426

Surface Hardness of Resin Cement Polymerized under Different Ceramic Materials  

PubMed Central

Objectives. To evaluate the surface hardness of two light-cured resin cements polymerized under different ceramic discs. Methods. 40 experimental groups of 2 light-cured resin cement specimens (Variolink Veneer and NX3) were prepared and polymerized under 5 different ceramic discs (IPS e.max Press HT, LT, MO, HO, and Cercon) of 4 thicknesses (0.5, 1.0, 1.5, and 2.0?mm), Those directly activated of both resin cements were used as control. After light activation and 37°C storage in an incubator, Knoop hardness measurements were obtained at the bottom. The data were analyzed with three-way ANOVA, t-test, and one-way ANOVA. Results. The KHN of NX3 was of significantly higher than that of Variolink Veneer (P < 0.05). The KHN of resin cement polymerized under different ceramic types and thicknesses was significant difference (P < 0.05). Conclusion. Resin cements polymerized under different ceramic materials and thicknesses showed statistically significant differences in KHN. PMID:22548062

Kesrak, Pimmada; Leevailoj, Chalermpol

2012-01-01

427

Cariogenic bacteria degrade dental resin composites and adhesives.  

PubMed

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

2013-11-01

428

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

429

Detoxification of lignocellulose hydrolysates with ion-exchange resins.  

PubMed

Lignocellulose hydrolysates contain fermentation inhibitors causing decreased ethanol production. The inhibitors include phenolic compounds, furan aldehydes, and aliphatic acids. One of the most efficient methods for removing inhibiting compounds prior to fermentation is treatment of the hydrolysate with ion-exchange resins. The performance and detoxification mechanism of three different resins were examined: an anion exchanger, a cation exchanger, and a resin without charged groups (XAD-8). A dilute acid hydrolysate of spruce was treated with the resins at pH 5.5 and 10.0 prior to ethanolic fermentation with Saccharomyces cerevisiae. In addition to the experiments with hydrolysate, the effect of the resins on selected model compounds, three phenolics (vanillin, guaiacol, and coniferyl aldehyde) and two furan aldehydes (furfural and hydroxymethyl furfural), was determined. The cation exchanger increased ethanol production, but to a lesser extent than XAD-8, which in turn was less effective than the anion exchanger. Treatment at pH 10.0 was more effective than at pH 5.5. At pH 10.0, the anion exchanger efficiently removed both anionic and uncharged inhibitors, the latter by hydrophobic interactions. The importance of hydrophobic interactions was further indicated by a substantial decrease in the concentration of model compounds, such as guaiacol and furfural, after treatment with XAD-8. PMID:11963864

Nilvebrant, N O; Reimann, A; Larsson, S; Jönsson, L J

2001-01-01

430

Comparative analysis of polymerization shrinkage of different resin composites.  

PubMed

This study sought to compare the shrinkage of 3 resin composites after polymerization, using different curing modes and 2 methods of analysis, with 45 samples in each group. To evaluate free linear shrinkage, specimens were prepared in Teflon molds (8 mm diameter x 2 mm thick) with 1 of 2 methacrylate-based resins or a silorane-based resin. To evaluate wall-to-wall shrinkage, cavities (1.5 mm thick x 3 mm diameter) were prepared in 45 healthy bovine incisors and then restored. In both tests, the same curing lights were used: conventional quartz-tungsten-halogen, a conventional light-emitting diode (LED), and an exponential LED. Gaps were measured microscopically, and the gap percentage was calculated. The results were analyzed by 2-way ANOVA and Tukey's test (? = 0.05). Curing modes differed significantly in the free linear shrinkage test group, while resin composites did not. In the wall-to-wall shrinkage group, there were significant differences between the resin composites. PMID:25734285

Barretto, Iana Coutinho; Pontes, Luana Farias; Carneiro, Karina Kato; Araujo, Jesuina Lamartine Nogueira; Ballester, Rafael Yague; Silva, Cecy Martins

2015-01-01

431

Tetrapod-like zinc oxide whisker enhancement of resin composite.  

PubMed

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 direct contact test. Optical microscopy, scanning electron microscopy, and measurements of the flexural strength, compressive strength, and diametral tensile strength were carried out for mechanical characterization. The results revealed that T-ZnOw provided the resin with strong antibacterial activity and improved mechanical properties in all tested groups. However, the antibacterial activity of the resin with 10% T-ZnOw in the powder component significantly decreased after aging treatment. The incorporation of 5% T-ZnOw into the resin powder was optimal to give appropriate antibacterial activity, long-term antibacterial effectiveness, and mechanical properties. PMID:20439932

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

2010-07-01

432

Innovative Resin Transfer and Disposition at Indian Point Unit 1  

SciTech Connect

A number of sites have both operating and shuttered nuclear facilities. Reducing dose to the caretakers can have beneficial effects for other site personnel who may work or pass near the shuttered facility. Furthermore, disposition of waste can have a positive effect on NRC required regular reporting of, and plans for the disposition of on-site wastes. Entergy's Indian Point Energy Center recently reduced the on-site curie load by working with RWE NUKEM and WMG, Inc. to innovatively free and ship nearly 1,000 cubic feet and nearly 600 curies of 30 year old resin and sludge from Unit 1. Old drawings, operations logs, were consulted and transfer lines were remotely checked. The tank selection sequence was primarily based on dose rates. System modifications to facilitate resin transfer were made on the lowest dose tanks first to gain current operating experience. Resin transfers were performed in accordance with the procedures developed, into waiting cask with appropriate waste containers. Decomposed resin of varying consistency could clog discharge lines and operational changes were made to mitigate against flow interruptions. Hydrogen buildup in the tanks was carefully addressed while solidified resin remains a challenge to be overcome. (authors)

Posivak, E.J.; Freitag, A.A.; Miller, R.J. [WMG, Inc., Peekskill, NY (United States)

2007-07-01

433

Westinghouse Modular Grinding Process - Enhancement of Volume Reduction for Hot Resin Supercompaction - 13491  

SciTech Connect

In nuclear power plants (NPP) ion exchange (IX) resins are used in several systems for water treatment. Spent resins can contain a significant amount of contaminates which makes treatment for disposal of spent resins mandatory. Several treatment processes are available such as direct immobilization with technologies like cementation, bitumisation, polymer solidification or usage of a high integrity container (HIC). These technologies usually come with a significant increase in final waste volume. The Hot Resin Supercompaction (HRSC) is a thermal treatment process which reduces the resin waste volume significantly. For a mixture of powdered and bead resins the HRSC process has demonstrated a volume reduction of up to 75 % [1]. For bead resins only the HRSC process is challenging because the bead resins compaction properties are unfavorable. The bead resin material does not form a solid block after compaction and shows a high spring back effect. The volume reduction of bead resins is not as good as for the mixture described in [1]. The compaction properties of bead resin waste can be significantly improved by grinding the beads to powder. The grinding also eliminates the need for a powder additive.Westinghouse has developed a modular grinding process to grind the bead resin to powder. The developed process requires no circulation of resins and enables a selective adjustment of particle size and distribution to achieve optimal results in the HRSC or in any other following process. A special grinding tool setup is use to minimize maintenance and radiation exposure to personnel. (authors)

Fehrmann, Henning [Westinghouse Electric Germany GmbH, Dudenstr. 44, D-68167 Mannheim (Germany)] [Westinghouse Electric Germany GmbH, Dudenstr. 44, D-68167 Mannheim (Germany); Aign, Joerg [Westinghouse Electric Germany GmbH, Global D and D and Waste Management, Tarpenring 6, D-22419 Hamburg (Germany)] [Westinghouse Electric Germany GmbH, Global D and D and Waste Management, Tarpenring 6, D-22419 Hamburg (Germany)

2013-07-01

434

The use of ultraviolet LED illumination for composite resin removal: an in vitro study.  

PubMed

It may be difficult to recognize composite resin restorations that are correctly shade-matched and well-placed by visual and tactile inspection alone--which can make the replacement of an existing resin restoration challenging. Many composite resins fluoresce under UV light, which can help dentists to detect resin material. This article explores a technique that utilizes a UV LED to cause composite resin to fluoresce. A UV/visible light spectrofluorometer was used to measure fluorescence excitation and emission maxima of 14 composite resin brands. Control samples of dentin and enamel were measured in a similar manner. Subsequently, each brand of composite resin was placed in extracted teeth and relative fluorescence was assessed. The composite resins were then removed and each tooth was inspected using UV light to detect remaining resin. Results from this study indicated that the optimal excitation wavelength was 385-395 nm, while 460 nm was determined to be the mean emission maxima. This study revealed three types of resin: highly fluorescent, moderately fluorescent, and weakly fluorescent. In each instance, the UV light revealed the presence of resin after all resin was believed to have been removed. Based on the results of this study, the use of UV illumination can be a useful technique for determining if composite resin has been removed completely. PMID:20829156

Bush, Mary A; Hermanson, Arnold S; Yetto, Robert J; Wieczkowski, Gerard

2010-01-01

435

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

436

Surface treatment of gold alloys for resin adhesion.  

PubMed

This in vitro study compared three methods of surface treating gold alloys to improve resin adhesion. The tensile bond strengths and modes of failure between specimen pairs cemented with a chemically adhesive resin were recorded. Heat-treated gold alloy specimens were significantly more resistant to bond failure under tensile loading than were either alumina-blasted or tin-plated gold specimens. There was no statistically significant difference in bond failure between alumina-blasted and tin-plated gold specimens. The surface treatment altered the mode of failure from adhesive and/or adhesive-cohesive for alumina-blasted and tinplated gold specimens to cohesive (within the resin) for heat-treated gold specimens. Three case reports are presented to illustrate clinical applications of heat-treated gold alloys. PMID:9063210

Eder, A; Wickens, J

1996-01-01

437

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

438

Chairside prefabricated fiber-reinforced resin composite fixed partial dentures.  

PubMed

The introduction of pre-impregnated fiber-reinforced resin composites has provided the dental profession with the opportunity to fabricate and deliver adhesive, esthetic, and metal-free tooth replacements. Utilizing this technology, a prefabricated fiber-reinforced resin composite fixed partial denture prototype that allows rapid, cost-effective, and noninvasive fixed tooth replacement for single anterior teeth has been developed. Ideal situations for this type of service include: a fixed replacement following tooth loss from trauma; a fixed tooth replacement in medically compromised patients who cannot sit for extended periods of time or have local anesthesia; periodontally compromised abutments; a fixed space maintainer following orthodontic movement; and a fixed provisional during the post implant healing phase prior to loading. This article describes the framework construction and placement protocol for the prefabricated fiber-reinforced resin composite fixed partial denture. PMID:12066682

Meiers, J C; Freilich, M A

2001-02-01

439

Evaluation of resin composites modified with nanogold and nanosilver.  

PubMed

Silver and gold have been used for centuries as antimicrobial agents. The aim of the study was to investigate diametral tensile strength, microhardness, ion release and light transmission of experimental resin composites. Flowable dental composite SDR (Dentsply, United Kingdom) was modified by nanogold, nanosilver and silica addition. The metal ion release, light transmission study, microhardness, Diametral Tensile Strength were evaluated. The experimental nanosilver-containing composites released significant amounts of Al, Si, Sr and Ba ions up to 30 days, and negligible silver ion amounts. Significant Ag ion release occurred in nanosilver- and nanogoldmodified composite. Resin composites modified with nanogold and nanosilver deposited on silica carrier exhibit lower light transmission and have opaque appearance. All experimental composites exhibited higher microhardness in comparison to non-modified resin composites. Diametral Tensile Strength of the experimental composites was comparable to the control group. PMID:24708202

?Soko?owski, Jerzy; Szynkowska, Ma?gorzata Iwona; Kleczewska, Joanna; Kowalski, Zygmunt; Sobczak-Kupiec, Agnieszka; Pawlaczyk, Aleksandra; Soko?owski, Krzysztof; ?ukomska-Szyma?ska, Monika

2014-01-01

440

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

441

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

442

In Situ Floating Resin Cranioplasty for Cerebral Decompression  

PubMed Central

The purpose of this report is to describe our surgical experiences in the treatment of cerebral decompression with in situ floating resin cranioplasty. We included in this retrospective study 7 patients who underwent in situ floating resin cranioplasty for cerebral decompression between December 2006 and March 2008. Of these patients, 3 patients had traumatic brain injury, 3 cerebral infarction, and one subarachnoid hemorrhage due to aneurysmal rupture. In situ floating resin cranioplasty for cerebral decompression can reduce complications related to the absence of a bone flap and allow reconstruction by secondary cranioplasty without difficulty. Furthermore, it provides cerebral protection and selectively eliminates the need for secondary cranioplasty in elderly patients or patients who have experienced unfavorable outcome. PMID:19893737

Ahn, Duck-Hyung; Kang, Sung-Don

2009-01-01

443

Stability and demulsification of emulsions stabilized by asphaltenes or resins.  

PubMed

Experimental data are presented to show the influence of asphaltenes and resins on the stability and demulsification of emulsions. It was found that emulsion stability was related to the concentrations of the asphaltene and resin in the crude oil, and the state of dispersion of the asphaltenes and resins (molecular vs colloidal) was critical to the strength or rigidity of interfacial films and hence to the stability of the emulsions. Based on this research, a possible emulsion minimization approach in refineries, which can be implemented utilizing microwave radiation, is also suggested. Comparing with conventional heating, microwave radiation can enhance the demulsification rate by an order of magnitude. The demulsification efficiency reaches 100% in a very short time under microwave radiation. PMID:14972628

Xia, Lixin; Lu, Shiwei; Cao, Guoying

2004-03-15

444

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

445

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

446

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

447

78 FR 56734 - Certain Rubber Resins and Processes for Manufacturing Same; Commission Determination To Review...  

Federal Register 2010, 2011, 2012, 2013, 2014

...TRADE COMMISSION [Investigation No. 337-TA-849] Certain Rubber Resins and Processes for Manufacturing Same; Commission Determination...or sale after importation into the United States of certain rubber resins by reason of misappropriation of trade secrets,...

2013-09-13

448

40 CFR 63.524 - Standards for wet strength resins manufacturers.  

Code of Federal Regulations, 2010 CFR

...POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon Polyamides Production § 63.524 Standards for wet strength resins manufacturers. (a) Owners or operators of...

2010-07-01

449

40 CFR 63.524 - Standards for wet strength resins manufacturers.  

Code of Federal Regulations, 2011 CFR

...POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon Polyamides Production § 63.524 Standards for wet strength resins manufacturers. (a) Owners or operators of...

2011-07-01

450

40 CFR 63.523 - Standards for basic liquid resins manufacturers.  

Code of Federal Regulations, 2010 CFR

...POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon Polyamides Production § 63.523 Standards for basic liquid resins manufacturers. (a) Owners or operators of...

2010-07-01

451

40 CFR 63.523 - Standards for basic liquid resins manufacturers.  

Code of Federal Regulations, 2011 CFR

...POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon Polyamides Production § 63.523 Standards for basic liquid resins manufacturers. (a) Owners or operators of...

2011-07-01

452

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...

453

Process for preparing phenolic formaldehyde resole resin products derived from fractionated fast-pyrolysis oils  

DOEpatents

A process for preparing phenol-formaldehyde resole resins and adhesive compositions in which portions of the phenol normally contained in said resins are replaced by a phenol/neutral fractions extract obtained from fractionating fast-pyrolysis oils.

Chum, Helena L. (Arvada, CO); Kreibich, Roland E. (Auburn, WA)

1992-01-01

454

78 FR 11627 - Certain Granular Polytetrafluoroethylene Resin From Italy: Rescission of Antidumping Duty...  

Federal Register 2010, 2011, 2012, 2013, 2014

...A-475-703] Certain Granular Polytetrafluoroethylene Resin From Italy: Rescission of Antidumping Duty Administrative Review; 2011-2012...granular polytetrafluoroethylene (``PTFE'') resin from Italy. The period of review is August 1, 2011, through July...

2013-02-19

455

76 FR 29008 - Granular Polytetrafluoroethylene Resin From Italy; Correction of Notice of Scheduling  

Federal Register 2010, 2011, 2012, 2013, 2014

...Third Review)] Granular Polytetrafluoroethylene Resin From Italy; Correction of Notice of Scheduling AGENCY: United States...antidumping duty order on granular polytetrafluoroethylene resin from Italy. CORRECTION: The Commission hereby corrects the...

2011-05-19

456

Vinyl Ester Resin: Rheological Behaviors, Curing Kinetics, Thermomechanical, and Tensile Properties  

E-print Network

Vinyl Ester Resin: Rheological Behaviors, Curing Kinetics, Thermomechanical, and Tensile Properties, thermomechanical properties, tensile mechanical properties Introduction The development of vinyl ester resins (VERs rheometry (TSR),7 and dynamic-mechanical thermal analysis.8 For the isothermal curing process

Guo, John Zhanhu

457

Resin/fiber thermo-oxidative interactions in PMR polymide/graphite composites  

NASA Technical Reports Server (NTRS)

The amounts of resin weight loss and fiber weight loss in four PMR-polyimide graphite fiber composites were calculated from the composite weight losses and the fiber/resin ratios of the composites after long term thermo-oxidative aging in 600 F air. The accelerating effect of graphite fiber on resin weight loss, compared to neat resin weight loss, indicated the presence of a deleterious resin/fiber thermo-oxidative interaction, presumably due to fiber impurities. Similarly, the decelerating effect of the protective matrix resin on fiber weight loss, compared to bare fiber weight loss, was also demonstrated. The amount of hydrazine-indigestible resin and the amount of loose surface graphite fiber that formed during 600 deg F exposure of the composites were quantitatively determined. The indigestible residual resin was also qualitatively studied by scanning electron microscopy.

Alston, W. B.

1979-01-01

458

Coupling Peptides To Resin For Affinity Purification Claire Walczak January 1996  

E-print Network

Coupling Peptides To Resin For Affinity Purification Claire Walczak January 1996 We use Affigel-10 until a wet cake is formed. Do not dry the resin completely or you will introduce lots of air bubbles

Mitchison, Tim

459

Inhibition of Dioxins in Combustion of Printed Wiring Boards by Use of Hydrogenated Alicyclic Epoxy Resin  

NASA Astrophysics Data System (ADS)

The amount of halogenated dioxins in combustion gases of printed circuit boards depends on the concentration of halogen in the substrate, and also changes with resin structures to be applied. In this study, it was revealed that by combined use of fine aluminum hydroxide, phosphate flame retardant and alicyclic epoxy resin instead of halogenated epoxy resin or aromatic epoxy resin, these printed circuit boards met UL94-V0 flammability classification. Furthermore halogenated dibenzodioxin/dibenzofuran was hardly detected in combustion gases. The printed circuit boards which consisted of alicyclic epoxy resin could control generating of halogenated dioxins, as compared with aromatic resin. According to the heat decomposition behavior, it was suggested that alicyclic resin was easy to decompose because of weak C-C bond strength and generating of halogenated dioxins were controlled by the structure of resins.

Mori, Takahiro; Saito, Seiichi; Saito, Shigemasa; Fujimoto, Kozo

460

Vitrification of cesium-contaminated organic ion exchange resin  

SciTech Connect

Vitrification has been declared by the Environmental Protection Agency (USEPA) as the Best Demonstrated Available Technology (BDAT) for the permanent disposal of high-level radioactive waste. Savannah River Site currently uses a sodium tetraphenylborate (NaTPB) precipitation process to remove Cs-137 from a wastewater solution created from the processing of nuclear fuel. This process has several disadvantages such as the formation of a benzene waste stream. It has been proposed to replace the precipitation process with an ion exchange process using a new resorcinol-formaldehyde resin developed by Savannah River Technical Center (SRTC). Preliminary tests, however, showed that problems such as crust formation and a reduced final glass wasteform exist when the resin is placed in the melter environment. The newly developed stirred melter could be capable of overcoming these problems. This research explored the operational feasibility of using the stirred tank melter to vitrify an organic ion exchange resin. Preliminary tests included crucible studies to determine the reducing potential of the resin and the extent of oxygen consuming reactions and oxygen transfer tests to approximate the extent of oxygen transfer into the molten glass using an impeller and a combination of the impeller and an external oxygen transfer system. These preliminary studies were used as a basis for the final test which was using the stirred tank melter to vitrify nonradioactive cesium loaded organic ion exchange resin. Results from this test included a cesium mass balance, a characterization of the semi-volatile organic compounds present in the off gas as products of incomplete combustion (PIC), a qualitative analysis of other volatile metals, and observations relating to the effect the resin had on the final redox state of the glass.

Sargent, T.N. Jr. [Clemson Univ., SC (United States)

1994-08-01

461

Degradation of resin composites in a simulated deep cavity.  

PubMed

The aim of this study was to analyze the sorption and solubility of a nanofilled (Filtek Z350) and a midifilled (Filtek P60) resin composite in oral environment-like substances, in a simulated deep cavity. A cylindrical cavity prepared in a bovine incisor root was incrementally filled with resin composites. The obtained resin composite cylinders were cut perpendicularly to the axis to obtain 1-mm-thick discs that were divided into fifteen groups (n=5) according to depth (1, 2, 3, 4 and 5 mm) and immersion media (distilled water - DW, artificial saliva - AS and lactic acid - LA). The sorption and solubility were calculated based on ISO 4049:2000. Additionally, the degree of conversion (DC%) was calculated by FT-IR spectroscopy. Data were analyzed using multifactor analysis of variance (MANOVA) followed by Tukey's HSD post-hoc test and linear regression analysis (a=0.05). The DC% was higher for the midifilled resin composite and was negatively influenced by cavity depth (p<0.05). The nanofilled resin composite presented higher sorption and solubility than did the midifilled (p<0.05). The immersion media influenced the sorption and the solubility as follows: LA>AS>DW, (p<0.05). Both phenomena were influenced by cavity depth, with the sorption and solubility increasing from 1 to 5 mm (p<0.05). The degradation of resin composite restorations may be greater in the deepest regions of class II restorations when the composite is exposed to organic acids present in the oral biofilm (lactic acid). PMID:25590201

Gonçalves, Luana; Amaral, Cristiane Mariote; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes; Silva, Eduardo Moreira da

2014-12-01

462

Toughened epoxy resin system and a method thereof  

DOEpatents

Mixtures of epoxy resins with cationic initiators are curable under high energy ionizing radiation such as electron beam radiation, X-ray radiation, and gamma radiation. The composition of this process consists of an epoxy resin, a cationic initiator such as a diaryliodonium or triarylsulfonium salt of specific anions, and a toughening agent such as a thermoplastic, hydroxy-containing thermoplastic oligomer, epoxy-containing thermoplastic oligomer, reactive flexibilizer, rubber, elastomer, or mixture thereof. Cured compositions have high glass transition temperatures, good mechanical properties, and good toughness. These properties are comparable to those of similar thermally cured epoxies.

Janke, C.J.; Dorsey, G.F.; Havens, S.J.; Lopata, V.J.

1998-03-10

463

Toughened epoxy resin system and a method thereof  

DOEpatents

Mixtures of epoxy resins with cationic initiators are curable under high energy ionizing radiation such as electron beam radiation, X-ray radiation, and gamma radiation. The composition of this process consists of an epoxy resin, a cationic initiator such as a diaryliodonium or triarylsulfonium salt of specific anions, and a toughening agent such as a thermoplastic, hydroxy-containing thermoplastic oligomer, epoxy-containing thermoplastic oligomer, reactive flexibilizer, rubber, elastomer, or mixture thereof. Cured compositions have high glass transition temperatures, good mechanical properties, and good toughness. These properties are comparable to those of similar thermally cured epoxies.

Janke, Christopher J. (Oliver Springs, TN); Dorsey, George F. (Farragut, TN); Havens, Stephen J. (Knoxville, TN); Lopata, Vincent J. (Manitoba, CA)

1998-01-01

464

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

465

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

466

Immediate cantilevered resin-bonded bridgework: a case report.  

PubMed

Resin-bonded bridgework (RBB) is now an accepted alternative to conventional bridgework in specific cases. This article reviews the immediate replacement of two anterior teeth with the resin-bonded technique and describes the use of immediate cantilevered RBB in the aesthetic treatment of a patient with class II division II malocclusion on a moderate skeletal II base. Both maxillary lateral incisors were extracted and immediately replaced with cantilevered RBB. This simple and conservative approach produced an instant solution to a difficult aesthetic problem of proclined lateral incisors. The reported RBB continues to function successfully after 15 months. PMID:10860053

al-Wahadni, A M; Hussey, D L

1999-09-01

467

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

468

Advanced composites: Environmental effects on selected resin matrix materials  

NASA Technical Reports Server (NTRS)

The effects that expected space flight environment has upon the mechanical properties of epoxy and polyimide matrix composites were analyzed. Environmental phenomena covered water immersion, high temperature aging, humidity, lightning strike, galvanic action, electromagnetic interference, thermal shock, rain and sand erosion, and thermal/vacuum outgassing. The technology state-of-the-art for graphite and boron reinforced epoxy and polyimide matrix materials is summarized to determine the relative merit of using composites in the space shuttle program. Resin matrix composites generally are affected to some degree by natural environmental phenomena with polyimide resin matrix materials less affected than epoxies.

Welhart, E. K.

1976-01-01

469

MODELING AND SIMULATION OF SOLID FLUIDIZATION IN A RESIN COLUMN  

SciTech Connect

The objective of the present work is to model the resin particles within the column during fluidization and sedimentation processes using computation fluid dynamics (CFD) approach. The calculated results will help interpret experimental results, and they will assist in providing guidance on specific details of testing design and establishing a basic understanding of particle’s hydraulic characteristics within the column. The model is benchmarked against the literature data and the test data (2003) conducted at Savannah River Site (SRS). The paper presents the benchmarking results and the modeling predictions of the SRS resin column using the improved literature correlations applicable for liquid-solid granular flow.

Lee, S.

2014-06-24

470

Electrical properties of epoxy resin based nano-composites  

SciTech Connect

We investigate the electrical properties of composite materials prepared as nano and sub-micro scale metal-oxide particles embedded in a commercial resin. The filler particles are barium titanate and calcium copper titanate. The physical and structural characteristics of constituents and the fabricated composites are reported. The electrical characterization of the composite samples are performed with the time- and frequency-domain dielectric spectroscopy techniques. The electrical breakdown strength of samples with nano and sub-micron size particles have better electrical insulation properties than the unfilled resin.

Tuncer, Enis [ORNL; Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Paranthaman, Mariappan Parans [ORNL; Aytug, Tolga [ORNL; Sathyamurthy, Srivatsan [ORNL; More, Karren Leslie [ORNL; Li, Jing [ORNL; Goyal, Amit [ORNL

2007-01-01

471

Preliminary properties of a resin from ethynyl terminated materials  

NASA Technical Reports Server (NTRS)

A blend composed of an ethynyl terminated aspartimide (brittle component) and an ethynyl terminated arylene ether oligomer (tough component) was thermally cured to yield a resin which underwent preliminary evaluation to determine the potential for use in structural applications on aerospace vehicles. The blend exhibited good compression moldability, allowing for fabrication of neat moldings, adhesive specimens and composites at temperatures of 250 C under a pressure of 1.4 MPa (200 psi). Neat resin moldings and adhesive specimens provided relatively high mechanical properties. Composite specimens provided promising results in spite of fiber misalignment, fiber washout, and a small amount of panel warpage.

Hergenrother, Paul M.; Connell, John W.

1991-01-01

472

Composition and method for making polyimide resin-reinforced fabric  

NASA Technical Reports Server (NTRS)

A composition for making polyimide resin reinforced fibers or fabric is discussed. The composition includes a polyfunctional ester, a polyfunctional amine, and an end capping agent. The composition is impregnated into fibers or fabric and heated to form prepreg material. The tack retention characteristics of this prepreg material are improved by incorporating into the composition a liquid olefinic material compatible with the other ingredients of the composition. The prepreg material is heated at a higher temperature to effect formation of the polyimide resin and the monomeric additive is incorporated in the polyimide polymer structure.

Serafini, T. T.; Delvigs, P. (inventors)

1981-01-01

473

The effect of molecular architecture on the mechanical properties of epoxy resin systems  

E-print Network

for the degree of MASTER OF SCIENCE May 1992 Major Subject: Mechanical Engineering THE EFFECT OF MOLECULAR ARCHITECTURE ON THE MECHANICAL PROPERTIES OF EPOXY RESIN SYSTEMS A Thesis bY GALE ANTRUS HOLMES Approved as to style an content by: Alan Let. ton... tougheness has been achieved in thermoset epoxy resins of relatively low Tg , &373 K. For epoxy resins to be used in aircraft structures, published specifications (54) indicate that the desirable properties of a resin should include a thermal performance...

Holmes, Gale Antrus

1992-01-01

474

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

475

An investigation of the anion-exchange resin method for soil phosphate extraction  

Microsoft Academic Search

Summary  The anion-exchange resin method for soil-phosphate extraction was investigated on 4 different soils under varying experimental\\u000a conditions. The variables were: (a) the type of anion-exchange resin, (b) the anionic form of the resin, (c) the ratio between\\u000a the amounts of resin, soil, and water, and (d) the time of shaking.\\u000a \\u000a The amount of P extracted was dependent on the anionic

Erik Sibbesen

1978-01-01

476

Fracture frequency and longevity of fractured resin composite, polyacid-modified resin composite, and resin-modified glass ionomer cement class IV restorations: an up to 14 years of follow-up  

Microsoft Academic Search

The aim of this study was to evaluate the fracture frequency and longevity of fractured class IV resin composite (RC), polyacid-modified\\u000a resin composite (compomer; PMRC), and resin-modified glass ionomer cement (RMGIC) restorations in a longitudinal long-term\\u000a follow-up. Eighty-five class IV RC (43: Pekafil), PMRC (24: Dyract (D), Hytac (H)), and RMGIC (18: Fuji II LC (F), Photac\\u000a Fil (P)) restorations

Jan W. V. van Dijken; Ulla Pallesen

2010-01-01

477

Effect of Resins and DBSA on Asphaltene Precipitation from Petroleum Fluids  

E-print Network

Effect of Resins and DBSA on Asphaltene Precipitation from Petroleum Fluids Lamia Goual and Abbas different petroleum fluids. Various resins are added to three different petroleum fluids to measure of precipitation. However, addition of resins to a petroleum fluid increases the amount of precipitated asphaltenes

Firoozabadi, Abbas

478

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

479

Use of ionizing radiation for fixing textile resins on wool. [Gamma rays  

SciTech Connect

Ambient-temperature treatments with ionizing radiation can be used as an alternative to conventional thermal/catalytic cure methods of fixing textile resins on wool materials. The effectiveness of the radiation-induced fixation of resins on wool has been demonstrated by machine-wash shrinkage tests on fabrics treated with a variety of commercial polymer resins.

McLaren, K.G.

1980-04-01

480

NON-ISOTHERMAL INJECTION MOULDING WITH RESIN CURE AND PREFORM DEFORMABILITY  

E-print Network

Transfer Molding), SRIM (Structural Resin Injection Molding), SCRIMP (Seeman Com- posite Resin Infusion. This is particularly evident near the injection port where the liquid matrix entering the mold may push awayNON-ISOTHERMAL INJECTION MOULDING WITH RESIN CURE AND PREFORM DEFORMABILITY A. FARINA and L

Preziosi, Luigi

481

Disinfection of viable Pseudomonas stutzeri in ultrapure water with ion exchange resins  

Microsoft Academic Search

This study describes the disinfection of gram-negative bacteria, Pseudomonas stutzeri, isolated from ultrapure water (total organic carbon 5 ppb; effluent resistivity, > 18 M? cm at 25°C) with ion exchange resins using a batchwise procedure. A single bed of strong base anion exchange resin (SBAER) in OH? form shows disinfection ability; however, a bed of strong acid cation exchange resin

Nae Matsuda; Wataru Agui; Keizo Ogino; Norimichi Kawashima; Tokeru Watanabe; Hideki Sakai; Masahiko Abe

1996-01-01

482

Solid-state storage of Ag nanoparticles in anion exchange resin beads and their recovery  

Microsoft Academic Search

This paper reports the idea and describes a method of reversible storage and recovery of silver nanoparticles (NPs) in anion exchange resin beads based on the principle of ion exchange. We also report that similar exchange of NPs was not possible with cation exchange resins. The Ag NPs were stored by simple exchange of anions of the resins, which were

S. Manikandan; G. Majumdar; D. Chowdhury; A. Paul; Arun Chattopadhyay

2006-01-01

483

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...

484

Synthesis and characterization of hyperbranched and air drying fatty acid based resins  

Microsoft Academic Search

In this research four hyperbranched resins having fatty acid residues were synthesized. Dipentaerythritol, which was used as the core molecule of the resins, was twice esterified with dimethylol propionic acid. This resin was then esterified with the castor oil fatty acids. The hydroxyl group present in the ricinoleic acid which constitutes almost 87% of the castor oil fatty acids was

Erhan Bat; Güngör Gündüz; Duygu K?sakürek; ?dris M. Akhmedov

2006-01-01

485

Development of polyamide curable modified epoxy novolac resins with improved adhesion and chemical resistance  

Microsoft Academic Search

Purpose – To prepare modified epoxy resins from resorcinol, cresol and phenol for improved adhesion and chemical resistance. To evaluate the properties of such modified epoxy resins. Design\\/methodology\\/approach – Epoxy novolac resins (ENRs) were synthesised by condensing epichlorohydrin with novolacs based on different types of substituted phenols for improving adhesion and chemical resistance. Various compositions were made by incorporating different

Vipin Shukla; Ravi Shukla; Dharmendra Singh; Mahendra Singh; Madhu Bajpai; Sunita Seth

2005-01-01

486

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

E-print Network

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. Metabolomic analysis of resin from 6 North American Populus spp. and 5 hybrids revealed peaks characteristic

Weiblen, George D

487

More conservative dentistry: Clinical long-term results of direct composite resin restorations.  

PubMed

Current treatment protocols and recent developments in composite resin technology allow for extended indication of direct composite resin restorations. This article presents clinical longterm observations of direct composite resin restorations indicated for primary and replacement therapy, repair restorations, direct crowns, and composite buildups for the correction of tooth form. PMID:25821863

Staehle, Hans Jörg; Wolff, Diana; Frese, Cornelia

2015-01-01

488

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

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Urea-formaldehyde resins in molded articles. 177.1900...Contact Surfaces § 177.1900 Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins may be safely used as the...

2014-04-01

489

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

Code of Federal Regulations, 2010 CFR

...2010-04-01 2009-04-01 true Urea-formaldehyde resins in molded articles. 177.1900...Contact Surfaces § 177.1900 Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins may be safely used as the...

2010-04-01

490

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

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Urea-formaldehyde resins in molded articles. 177.1900...Contact Surfaces § 177.1900 Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins may be safely used as the...

2012-04-01

491

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

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Urea-formaldehyde resins in molded articles. 177.1900...Contact Surfaces § 177.1900 Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins may be safely used as the...

2013-04-01

492

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

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Urea-formaldehyde resins in molded articles. 177.1900...Contact Surfaces § 177.1900 Urea-formaldehyde resins in molded articles. Urea-formaldehyde resins may be safely used as the...

2011-04-01

493

Influence of interfacial reaction on interfacial performance of carbon fiber and polyarylacetylene resin composites  

Microsoft Academic Search

The influence of interfacial reaction on interfacial performance of carbon fiber\\/polyarylacetylene resin composites was studied. For this purpose, vinyltrimethoxysilane containing a double bond was grafted onto the carbon fiber surface to react with the triple bond of polyarylacetylene resin. The reaction between polyarylacetylene resin and vinyltrimethoxysilane was proved by reference to the model reaction between phenylacetylene and vinyltrimethoxysilane. Surface chemical

Z. X. Jiang; Y. D. Huang; L. Liu; C. Lu

2008-01-01

494

Characteristics of Boron Epoxy Resin as a Gasket for Pressure Generation in the 20 GPa Region  

Microsoft Academic Search

Boron and epoxy-resin gaskets were characterized in terms of pressure generation in the 20 GPa region using a Bridgman-type opposed anvil apparatus made of sintered diamond (SD). As compared to pyrophyllite, boron and epoxy resin exhibited markedly large internal friction. It was recognized that the properties of boron and epoxy resin as a gasket can be modified by changing their

Takashi Taniguchi; Osamu Shimomura; Shinobu Yamaoka

1993-01-01

495

Synthesis and Characterization of Novel Multiaromatic Epoxy Resin for Advanced Microelectronic Packaging Applications  

Microsoft Academic Search

The novel multiaromatic epoxy resin and hardener was synthesized and characterized. The mechanical, thermal, electrical as well as flame retardant properties of cured epoxy resins were systematically investigated. Experiment results indicated that the cured novel multiaromatic resins exhibited very good mechanical properties, good electrical properties, high glass transition temperature, good dielectric properties, low moisture absorption and very good flame retardancy.

Zhiqiang Lao; Jiapei Ding; Haixia Yang; Lin Fan; Shiyong Yang

2007-01-01

496

Multicomponent anion exchange with a resin having weakly and strongly basic groups  

Microsoft Academic Search

Multicomponent anion exchange with a resin having both weakly and strongly basic groups was investigated by means of modelling and column experiments. Our objective was to develop a model able to predict the evolution of the composition of a water treated by such a resin. The studied resin was Purolite S108, used for boron removal from water, on which ternary

Marie-Odile Simonnot; Stéphanie Ouvrard

2005-01-01

497

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...

498

A comparison of fatigue crack growth in resin composite, dentin and the interface  

Microsoft Academic Search

Objectives. The objective of this in vitro study was to evaluate the fatigue crack growth prop- erties of the dentin\\/resin adhesive interface. Methods. Compact tension (CT) specimens were prepared from coronal dentin, resin compos- ite, and dentin bonded to resin composite using Optibond Solo Plus adhesive. All specimens were then subjected to cyclic Mode I loading while fully hydrated at

Matthew J. Soappman; Ahmad Nazari; Judith A. Porter; D. Arolaa

2007-01-01

499

Shear Bond Strength of AH26 and Epiphany to Composite Resin and Resilon  

Microsoft Academic Search

The aim of this study was to evaluate the relative bond strengths of AH-26 and Epiphany sealers to both Resilon and composite resin. Four groups of substrate\\/bonded sealer combinations were tested: group A, composite resin substrate + Epiphany sealer; group B, composite resin substrate + AH-26 sealer; group C, Resilon substrate + Epiphany sealer; and group D, Resilon substrate +

Christos Gogos; Vicky Theodorou; Nikolaos Economides; Panagiotis Beltes; Ioannis Kolokouris

2008-01-01

500

Curing and post-curing luminescence in an epoxy resin O. Gallot-lavalle 1  

E-print Network

of Applied Polymer Science Keywords: Epoxy resin, Luminescence, Thermo-stimulation, Chemiluminescence, Post a chemiluminescence process during oxidation. Keywords Epoxy resin, Luminescence, Thermo-stimulation, Chemiluminescence, Post curing, Thermal endurance #12;3 1 INTRODUCTION Epoxy resins are widely used as electrical

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