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Process Development of 2,2-Dinitropropyl Acrylate

Description: Abstract: Developmental production of approximately 500 pounds of 2,2-dinitropropanol and 250 pounds of 2,2-dinitropropyl acrylate was carried out in a 50-gallon capacity stainless-steel reactor system. The intermediate alcohol was produced in a yield of 73%. The ester was made with a yield of 78%. Cost studies show that the manufacturing cost for DNPA monomer should approximate $2.70 per pound on a production basis of 30,000 pounds, with an indicated plant cost of $4.60 per pound for the polymeric form.
Date: October 1955
Creator: Benziger, T. M.; Rohwer, R. K. & Stein, W. H.
Partner: UNT Libraries Government Documents Department

In-situ property measurements on laser-drawn strands of SL 5170 epoxy and SL 5149 acrylate

Description: Material behavior plays a significant role in the mechanics leading to internal stresses and, potentially, to distortion (curling) of parts as they are built by stereolithography processes that utilize photocuring resins. A study is underway to generate material properties that can be used to develop phenomenological material models of epoxy and acrylate resins. Strand tests are performed in situ in a 3D System`s SLA-250 machine; strands are drawn by either single or multiple exposures of the resin to a laser beam. Linear shrinkage, cross-sectional areas, cure shrinkage forces and stress-strain data are presented. Also, the curl in cantilever beam specimens, built with different draw patterns, are compared.
Date: August 1, 1995
Creator: Guess, T.R. & Chambers, R.S.
Partner: UNT Libraries Government Documents Department

Development of porous polymer monoliths for reverse-phase chromatography of proteins.

Description: The polymers developed in this project are intended for use as a stationary phase in reverse-phase chromatography of proteins, where the mobile phase is a solution of acetonitrile and a phosphate buffer, 6.6 pH. A full library of pore sizes have been developed ranging from 0.41{micro}m to 4.09 {micro}m; these pore sizes can be determined by the solvent ratio of tetrahydrofuran:methoxyethanol during polymerization. A column that can separate proteins in an isocratic mode would be a vast improvement from the common method of separating proteins through gradient chromatography using multiple solvents. In the stationary phase, the main monomers have hydrophobic tails, lauryl acrylate and steryl acrylate. Separations of small hydrophobic molecules and peptides (trial molecules) have efficiencies of 24,000-33,000 theoretical plates m{sup -1}. The combination of a highly non-polar stationary phase and a mobile phase where the polarity can be controlled provide for excellent separation.
Date: September 1, 2003
Creator: Shepodd, Timothy J. (Sandia National Laboratories, Albuquerque, NM) & Stephens, Christopher P. (Sandia National Laboratories, Albuquerque, NM)
Partner: UNT Libraries Government Documents Department

Epoxy and acrylate stereolithography resins: In-situ measurements of cure shrinkage and stress relaxation

Description: Cross-sections of resin strands. Techniques were developed to make in situ measurements of gelled resin to determine linear shrinkage, stress-strain response and stress relaxation of single strands of SL 5170 epoxy and SL 5149 photocurable resins. Epoxy strands shrank approximately 1.4% and the acrylate strands about 1.0% after a single exposure. No forces were measured during cure shrinkage of strands following the first laser exposure. In multiple laser exposures, the acrylate continues to shrink; whereas (University of Dayton data) no additional shrinkage is observed in epoxy strands on a second hit. In force relaxation tests, a strand is drawn and then a 0.5% step strain is applied after different elapsed times. The epoxy initial modulus evolves (increases) with elapsed time following draw of the strand, and this evolution in modulus occurs after linear shrinkage has stopped. On the other hand, acrylates show no evolution of modulus with elapsed time following a single laser draw; i.e., once shrinkage stops after one laser hit, the initial modulus remains stable with elapsed time. Finally, relaxation response times of epoxy strands get larger with increasing elapsed time after laser draw. In acrylate strands there was no evolution in initial modulus with elapsed time after a single draw so relaxation times are not a function of elapsed time after a single hit with the laser.
Date: March 1, 1995
Creator: Guess, T.R.; Chambers, R.S.; Hinnerichs, T.D.; McCarty, G.D. & Shagam, R.N.
Partner: UNT Libraries Government Documents Department

Synthesis of acrylates and Methacrylates from Coal-Derived Syngas

Description: Research Triangle Institute (RTI), Eastman Chemical Company, and Bechtel collectively are developing a novel process for the synthesis of methyl methacrylate (MMA) from coal-derived syngas, under a contract from the U.S. Department of Energy, Federal Energy Technology Center. This three-step process consists of synthesis of a propionate, its condensation with formaldehyde, and esterification of resulting methacrylic acid (MAA) with methanol to produce MMA. Eastman has focused on the propionate synthesis step. The resultant Mo catalysts work efficiently at much less severe conditions (170{degrees}C and 30 atm) than the conventional Ni catalysts (270{degrees} C and 180 atm). Bechtel has performed an extensive cost analysis which shows that Eastman`s propionate synthesis step is competitive with other technologies to produce the anhydride. Eastman and Bechtel have also compared the RTI- Eastman-Bechtel three-step methanol route to five other process routes to MMA. The results show that the product MMA can be produced at 520/lb, for a 250 Mlb/year MMA plant, and this product cost is competitive to all other process routes to MMA, except propyne carbonylation. In the second step, RTI and Eastman have developed active and stable V-SI-P tertiary metal oxide catalysts, Nb/Si0{sub 2}, and Ta/Si0{sub 2} catalysts for condensation of propionic anhydride or propionic acid with formaldehyde. RTI has demonstrated a novel correlation among the catalyst acid-base properties, condensation reaction yield, and long-term catalyst performance. Eastman and Bechtel have used the RTI experimental results of a 20 percent Nb/Si0{sub 2} catalyst, in terms of reactant conversions, MAA selectivities, and MAA yield, for their economic analysis. Recent research focuses on enhancing the condensation reaction yields, a better understanding of the acid-base property correlation and enhancing the catalyst lifetime.
Date: May 12, 1997
Partner: UNT Libraries Government Documents Department

Complex formation of beta-cyclodextrin in aqueous media with poly(N,N-dimethylacrylamide)containing pendent perfluorooctanesulfonamido groups. Final Report, September 15, 1998 - September 14, 1999

Description: The effect of time on the viscosity of solutions of 0.50--1.0 weight % polyacrylamide copolymers containing 2-(N-ethylperfluorooctanesulfonamido)ethyl acrylate (FOSA) comonomer units was monitored at constant shear rates varying from 0.60 to 3.0 sec{sup {minus}1}. The viscosities decreased to a plateau over a period of about thirty minutes. The copolymer solutions sheared at much higher shear rates of 24 sec{sup {minus}1} showed pronounced shear thinning but regained most of their original viscosities after standing for 20 minutes. Heating the solutions less than one hour caused an increase in the low shear viscosity whereas longer heating times decreased solution viscosities presumably due to hydrolysis of the acrylate groups. Addition of beta-cyclodextrin to solutions of the hydrophobically modified polyacrylamide resulted in sharply decreased copolymer viscosities at cyclodextrin concentrations on the order of about 10{sup {minus}3} M. The above is consistent with competitive hydrophobic association of the perfluorocarbon groups of the copolymer with the cyclodextrin disrupting the mutual association of the perfluorocarbon groups.
Date: November 1, 1999
Creator: Hogen-Esch, Dr. Thieo
Partner: UNT Libraries Government Documents Department

Nanoparticles Engineered to Bind Serum Albumin: Microwave Assisted Synthesis, Characterization, and Functionalization of Fluorescently-Labeled, Acrylate-Based, Polymer Nanoparticles

Description: The potential use of polymeric, functionalized nanoparticles (NPs) as drug delivery vectors was explored. Covalent conjugation of albumin to the surface of NPs via maleimide chemistry proved problematic. However, microwave assisted synthesis of NPs was not only time efficient, but enabled the exploration of size control by changing the following parameters: temperature, microwave power, reaction time, initiator concentration, and percentage of monomer used. About 1.5 g of fluorescently-labeled, carboxylic acid-functionalized NPs (100 nm diameter) were synthesized for a total cost of less than $1. Future work will address further functionalization of the NPs for the coupling of albumin (or other targeted proteins), and tests for in vivo biodistribution.
Date: August 2010
Creator: Hinojosa, Barbara R.
Partner: UNT Libraries

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

Description: Ultraviolet light is known to be one of the most efficient methods to initiatc polymeric reactions in the presence of a photonitiator. Photopolymerizations are advantageous because the chemistry of the materials can be tailored to design liquid monomers for ultrarapid polymerization into a solid polymer material. One way to achieve rapid photopolymerizations is to utilize multifunctional (meth)acrylate monomers. which form highly crosslinked polymers; however, these monomers typically do not achieve complete functional group conversion. Recently, Decker et al. developed novel monovinyl acrylate monomers that display polyriicrization kinetics that rival those of multifunctional acrylate monomers. These novel acrylate monomers incorporate secondary functionalities and end groups such as carbonates, carbamates, cyclic carbonates and oxazolidone which promote the increased polymerization kinetics of these monomers. In addition to thc polynierization kinetics, these novel monovinyl monomers form crosslinked polymers, which are characterized by having high strength and high flexibility. Unfortunately, the exact mechanism or mechanisms responsible for the polymerization kinetics and crosslinking are not well understood.
Date: January 1, 2002
Creator: Beckel, E. R. (Eric R.); Berchtold, K. A. (Kathryn A.); Nie, J. (Jun); Lu, H. (Hui); Stansbury, J. W. (Jeffrey W.) & Bowman, C. N. (Christopher N.)
Partner: UNT Libraries Government Documents Department

Microbial engineering of nano-heterostructures; biological synthesis of a magnetically-recoverable palladium nanocatalyst

Description: Precious metals supported on ferrimagnetic particles form a diverse range of catalysts. Here we show a novel biotechnological route for the synthesis of a heterogeneous catalyst consisting of reactive palladium nanoparticles arrayed on a biomagnetite support. The magnetic support was synthesized at ambient temperature by the Fe(III)-reducing bacterium, Geobacter sulfurreducens, and facilitated ease of recovery of the catalyst with superior performance due to reduced agglomeration. Arrays of palladium nanoparticles were deposited on the nanomagnetite using a simple one-step method without the need to modify the biomineral surface most likely due to an organic coating priming the surface for Pd adsorption. A combination of EXAFS and XPS showed the particles to be predominantly metallic in nature. The Pd{sup 0}-biomagnetite was tested for catalytic activity in the Heck Reaction coupling iodobenzene to ethyl acrylate or styrene and near complete conversion to ethyl cinnamate or stilbene was achieved within 90 and 180 min, respectively.
Date: December 1, 2009
Creator: Coker, V. S.; Bennett, J. A.; Telling, N.; Charnock, J. M.; van der Laan, G.; Pattrick, R. A. D. et al.
Partner: UNT Libraries Government Documents Department

[Synthesis and characterization of novel associating water-soluble copolymers]: Annual progress report, November 15, 1993-November 15, 1994

Description: A large number of hydrophobically associating copolymers of N-vinylpyrrolidone (NVP) or N,N-dimethyl acrylamide (DMA) with perfluoroalkyl acrylates (FOSA) containing between .01 and 1.0 mole % FOSA (with respect to DMA) were synthesized by emulsion and by bulk copolymerization. In contrast with the acrylamide (AM) FOSA copolymers the corresponding NVP and DMA copolymers are soluble in THF and CH{sub 3}OH in addition to water. This is expected to be of help in the characterization. This report discusses the synthesis, the kinetics of AM-FOSA copolymerization, and characterization.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

RBS analysis of the diffusion of nano-size spheres in a polymer matrix

Description: Rutherford Backscattering Spectrometry (RBS) with 1.5-MeV He ions was employed to measure the depth distribution of gold particles sandwitched between two poly(tert-butyl acrylate) layers following various isothermal annealing treatments; temperatures were kept below 170{degrees}C to prevent degradation of the polymer. Since PTBA also degrades when the ion beam impinges the sample, it was necessary to quantify the mass loss in order to obtain accurate diffusion coefficients. Although the total mass loss was substantial (40-60%), a simple expansion of the energy-to-depth scale was sufficient to account for the beam-induced shrinkage. This result is attributed to the fact that the mass loss occurs very rapidly, and is uniformly distributed through the depth of the sample. The data reveal that the diffusion of the nanometer-size gold particles is substantially slower than is predicted by a simple physical model (Stokes-Einstein) for noninteracting particles. This slowdown is attributed to polymer bridging interactions, in which polymer strands bind to individual metal particles, thereby retarding their diffusion.
Date: August 1, 1997
Creator: Cole, D.H.; Shull, K.R.; Rehn, L.E. & Baldo, P.M.
Partner: UNT Libraries Government Documents Department

Reactivity of Metal Ions Bound to Water-Soluble Polymers

Description: The intent of this work is to determine the effectiveness of catalysts covalently bound to polymers and to understand the consequences of supporting the catalysts on catalyst efficiency and selectivity. Rhodium phosphine complexes with functional groups for coupling to polymers were prepared. These catalyst precursors were characterized using standard techniques including IR, NMR, and elemental analysis. Studies on the modified catalysts showed that they were still active hydrogenation catalysts. However, tethering of the catalysts to polyamines gave systems with low hydrogenation activity. Analogous biphasic systems were also explored. Phosphine ligands with a surfactant-like structure have been synthesized and used to prepare catalytically active complexes of palladium. The palladium complexes were utilized in Heck-type coupling reactions (e.g. coupling of iodobenzene and ethyl acrylate to produce ethyl cinnamate) under vigorously stirred biphasic reaction conditions, and were found to offer superior performance over a standard water-soluble palladium catalyst under analogous conditions.
Date: June 29, 1999
Creator: Sauer, N.N.; Watkins, J.G.; Lin, M.; Birnbaum, E.R.; Robison, T.W.; Smith, B.F. et al.
Partner: UNT Libraries Government Documents Department

Immobilized enzymes in organic media: Chiral monomer production in organic media. Final report

Description: The overall goals of this project were to investigate the critical factors that limit commercial scale applications of enzymes in organic solvents, and to scale-up a process for the production of a precursor to a specialty polymer. In the last phase of the project, we focused on optimizing and scaling up a trans-esterification reaction catalyzed by Subtilisin Carlsberg in very dry organic solvent. The reaction system we have employed has been reported. It involves the trans-esterification of vinyl acrylate with (R,S)-sec-(2-naphthyl)ethyl alcohol catalyzed by Subtilisin Carlsberg in tert-amyl-alcohol as a solvent. Only the S ester is produced. The other product, vinyl alcohol, converts spontaneously to acetaldehyde, thus shifting the equilibrium towards production of the desired product. The scaled up reaction was run under various conditions in order to identify the controlling factors. We have been able to scale up successfully the trans-esterification reaction from 5ml to 75ml. By varying the immobilization and reaction conditions, we increased the initial rate of the reaction by two orders of magnitude and the conversion from 20% to 100%. We have isolated several grams of the S-sec-(2-naphthyl)ethyl acrylate product. It contains two minor impurities, none of which is the R enantiomer. This and other chiral acrylic monomers could be polymerized to form polymers with special optical properties. In our dry enzymatic trans-esterification system, we found that two factors dominate the observed Subtilisin activity: Iyoprotection and water control. This is in agreement with other reports. Our results are consistent with the observed initial rate affected mostly by changes in the amount of active protease rather than in the enzyme`s intrinsic catalytic rate.
Date: March 1, 1996
Creator: Zemel, H.; Bedwell, B.W.; Kasper, M. & Marinelli, G.
Partner: UNT Libraries Government Documents Department

Synthesis, Characterization, to application of water soluble and easily removable cationic pressure sensitive adhesives

Description: In recent years, the world has expressed an increasing interest in the recycling of waste paper to supplement the use of virgin fiber as a way to protect the environment. Statistics show that major countries are increasing their use of recycled paper. For example, in 1991 to 1996, the U.S. increased its recovered paper utilization rate from 31% to 39%, Germany went from 50% to 60%, the UK went from 60% to 70%, France increased from 46% to 49%, and China went from 32% to 35% [1]. As recycled fiber levels and water system closures both increase, recycled product quality will need to improve in order for recycled products to compete with products made from virgin fiber [2]. The use of recycled fiber has introduced an increasing level of metal, plastic, and adhesive contamination into the papermaking process which has added to the complexity of the already overwhelming task of providing a uniform and clean recycle furnish. The most harmful of these contaminates is a mixture of adhesives and polymeric substances that are commonly known as stickies. Stickies, which enter the mill with the pulp furnish, are not easily removed from the repulper and become more difficult the further down the system they get. This can be detrimental to the final product quality. Stickies are hydrophobic, tacky, polymeric materials that are introduced into the papermaking system from a mixture of recycled fiber sources. Properties of stickies are very similar to the fibers used in papermaking, viz. size, density, hydrophobicity, and electrokinetic charge. This reduces the probability of their removal by conventional separation processes, such as screening and cleaning, which are based on such properties. Also, their physical and chemical structure allows for them to extrude through screens, attach to fibers, process equipment, wires and felts. Stickies can break down and ...
Date: January 30, 2004
Creator: Technology, Institute of Paper Science
Partner: UNT Libraries Government Documents Department

Preparation and Characterization of Paints and Coatings from Soy and Corn Oils

Description: This project was highly successful. A series of new waterborne polyurethane (PU)/acrylic hybrid latexes were successfully synthesized by the emulsion polymerization of acrylic monomers (butyl acrylate and methyl methacrylate) in the presence of a soybean oil-based waterborne PU dispersion using potassium persulfate as an initiator. The waterborne PU dispersion was synthesized by a polyaddition reaction of toluene 2,4-diisocyanate and a soybean oil-based polyol (SOL). The resulting hybrid latexes, containing 15-60 wt % SOL as a renewable resource, are very stable and exhibit uniform particle sizes of {approx}125 nm as determined by transmittance electronic microscopy. The structure, thermal, and mechanical properties of the resulting hybrid latex films have been investigated by Fourier transform infrared spectroscopy, solid state {sup 13}C NMR spectroscopy, dynamic mechanical analysis, extraction, and mechanical testing. Grafting copolymerization of the acrylic monomers onto the PU network occurs during the emulsion polymerization, leading to a significant increase in the thermal and mechanical properties of the resulting hybrid latexes. This work provides a new way of utilizing renewable resources to prepare environmentally friendly hybrid latexes with high performance for coating applications. In addition, a novel soybean oil-based vinyl-containing waterborne polyurethane (VPU) dispersion has been successfully synthesized from toluene 2,4-diisocyanate, dimethylol propionic acid and a 90:10 mixture of chlorinated soybean oil-based polyol and acrylated epoxidized soybean oil (AESO). Then, a series of VPU/acrylic grafted latexes were prepared by emulsion graft copolymerization of acrylic monomers (40 wt% butyl acrylate and 60 wt% methyl methacrylate) in the presence of the VPU dispersion using potassium persulfate as an initiator. The structure, morphology, and thermal and mechanical properties of the resulting latexes, containing 15-60 wt% soybean oil-based polyols as a renewable resource, were investigated by Fourier transform infrared spectroscopy, solid state {sup 13}C NMR spectroscopy, transmission electron microscopy, thermogravimetric analysis, dynamic mechanical analysis and mechanical testing. ...
Date: February 26, 2009
Creator: Larock, Richard C.
Partner: UNT Libraries Government Documents Department

Nanoscale chemical and mechanical characterization of thin films:sum frequency generation (SFG) vibrational spectroscopy at buriedinterfaces

Description: Sum frequency generation (SFG) surface vibrational spectroscopy was used to characterize interfaces pertinent to current surface engineering applications, such as thin film polymers and novel catalysts. An array of advanced surface science techniques like scanning probe microscopy (SPM), x-ray photoelectron spectroscopy (XPS), gas chromatography (GC) and electron microscopy were used to obtain experimental measurements complementary to SFG data elucidating polymer and catalyst surface composition, surface structure, and surface mechanical behavior. Experiments reported in this dissertation concentrate on three fundamental questions: (1) How does the interfacial molecular structure differ from that of the bulk in real world applications? (2) How do differences in chemical environment affect interface composition or conformation? (3) How do these changes correlate to properties such as mechanical or catalytic performance? The density, surface energy and bonding at a solid interface dramatically alter the polymer configuration, physics and mechanical properties such as surface glass transition, adhesion and hardness. The enhanced sensitivity of SFG at the buried interface is applied to three systems: a series of acrylates under compression, the compositions and segregation behavior of binary polymer polyolefin blends, and the changes in surface structure of a hydrogel as a function of hydration. In addition, a catalytically active thin film of polymer coated nanoparticles is investigated to evaluate the efficacy of SFG to provide in situ information for catalytic reactions involving small mass adsorption and/or product development. Through the use of SFG, in situ total internal reflection (TIR) was used to increase the sensitivity of SFG and provide the necessary specificity to investigate interfaces of thin polymer films and nanostructures previously considered unfeasible. The dynamic nature of thin film surfaces is examined and it is found that the non-equilibrium states contribute to practical applications of acrylates, blends and hydrogels. Lastly, nanoparticle surfaces and the catalytic activity and selectivity of ...
Date: May 19, 2006
Creator: Kweskin, S.J.
Partner: UNT Libraries Government Documents Department

Magnetic resonance imaging of solvent transport in polymer networks

Description: The spectroscopic technique of magnetic resonance imaging (MRI) has recently provided a new window into transport of solvents in polymer networks. Diffusion of solvent as a rate-controlling phenomenon is paramount to understanding transport in many important industrial and biological processes, such as upgrading fossil fuels, film casting and coating, development of photoresists, design of drug-delivery systems, development of solvent resistant polymers, etc. By MRI mapping the migration of solvent molecules through various polymer specimens, researchers Robert Botto and George Cody of Argonne National Laboratory, with support from the Division of Chemical Sciences at DOE, were able to characterize and distinguish between different modes of transport behavior associated with fundamentally different types of polymer systems. The method was applied to rubbers, glassy polymers, and coals. In polymers shown to undergo a glass transition from a rigid to rubbery state, a sharply defined solvent front was observed that propagated through specimens in the manner of a constant velocity shock wave. This behavior was contrasted with a smooth solvent concentration gradient found in polymer systems where no glass transition was observed. The results of this analysis have formed the basis of a new model of anomalous transport in polymeric solids and are helping to ascertain fundamental information on the molecular architectures of these materials.
Date: February 1, 1995
Creator: Botto, R.E. & Cody, G.D.
Partner: UNT Libraries Government Documents Department

uv radiation curable paints. Topical report on material identification

Description: The program for the development of ultraviolet radiation curing of paints for application on preformed structures is discussed. The starting point of this program was the matching of resins, photoinitiators, and pigments which will result in coatings that can be cured by ultraviolet radiation. The initial work was the identification of reactive diluents and base resins that are sensitive to the uv curing process. The reactive monomeric diluents tested included multifunctional acrylates, monofunctional acrylates, and non-acrylic unsaturated esters. The end point will be the application of these coatings to prefabricated metal structures to demonstrate the viability of this technique in producing commercially acceptable painted products. These uv curable paints should produce films that are hard, adherent, and opaque at a nominal thickness of one mil (0.001 inch).
Date: January 13, 1981
Partner: UNT Libraries Government Documents Department

Dual cure low-VOC coating process. Phase 3, Semi-annual report, April 1, 1992--September 30, 1992

Description: The objective of Phase 3 of 3M`s contract with the US Department of Energy is to complete proof-of-principle testing in full-scale systems of the dual cure photocatalyst technology developed in earlier Phases of the program. The Phase 3 commercial applications to be demonstrated are aerospace topcoats, aerospace primers, and solventless manufacture of tape backings. This report details activities of Phase 3 during this reporting period. In the second six months of Phase 3, work has continued in all three applications. Significant progress has been made in improving the performance of the urethane/acrylate formulation being used for the aerospace topcoat application. Key improvements have been made in obtaining increased reverse impact, initial gloss and gloss retention during accelerated weathering. Technical challenges have continued with the aerospace primer formulation. Efforts in this six months have continued to focus on establishing a good baseline epoxy/acrylate formulation with reliable cure conditions. Work on the third demonstration application, development of solventless backing saturants for electrical tape backings, has essentially been completed. Optimal dual cure resin formulations have been identified and utilized in preparing complete tape constructions. These tapes have been evaluated and characterized in terms of benchmark UL and internal 3M specifications for electrical tape performance.
Date: October 1, 1993
Creator: Kinzer, K. E.
Partner: UNT Libraries Government Documents Department

Coal liquefaction and gas conversion contractors review conference: Proceedings

Description: This volume contains 55 papers presented at the conference. They are divided into the following topical sections: Direct liquefaction; Indirect liquefaction; Gas conversion (methane conversion); and Advanced research liquefaction. Papers in this last section deal mostly with coprocessing of coal with petroleum, plastics, and waste tires, and catalyst studies. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: November 1, 1995
Partner: UNT Libraries Government Documents Department

Dual cure photocatalyst systems

Description: A family of dual cure photocatalyst systems is being developed to be used in the solventless processing of organic coatings. The photocatalyst systems consist of organometallic compounds often in combination with other agents. Upon photolysis, the photocatalyst system generates a Lewis acid and a free radical. The Lewis acid can initiate the polymerization of epoxies or the addition of isocyanates and polyols to form polyurethanes while the free radical can initiate the polymerization of acrylates. The performance of the various photocatalyst systems will be compared on the basis of the physical properties of the cured compositions they produce. 17 figs.
Date: January 1, 1990
Creator: DeVoe, R.J.; Brown-Wensley, K.A.; Holmes, G.L.; Mathis, M.D.; McCormick, F.B.; Palazzotto, M.C. et al.
Partner: UNT Libraries Government Documents Department

Field trial of HTM-1

Description: The following mud-related problems were identified which are encountered in geothermal drilling: mud solidification, lost circulation, and corrosion. It was shown that mud solidification is related to the accumulation of bentonite from drilled solids as well as from additions of drilling mud bentonite. Mud solidification is aggravated by the thermal decomposition of thinners at temperatures encountered in geothermal drilling. Loss of mud is caused by low formation pressures, fractured reservoirs and pressure surges caused by high-temperature mud gelation. Rapid corrosion rates are experienced in geothermal drilling operations because of the high temperatures encountered, the intrusions of salt formation fluids, the decomposition of thinners into acidic by-products, the influx of hydrogen sulfide and carbon dioxide, and the erosional effects when air is used as a drilling fluid.
Date: January 1, 1979
Creator: Remont, L.J.
Partner: UNT Libraries Government Documents Department

New capabilities and applications for electrophoretically deposited coatings

Description: Our primary purpose in this test is to provide a brief general description of a few applications of various electrophoretic systems which have been investigated and have found use in various coating applications at Sandia National Laboratories. Both organic and inorganic suspensions in aqueous and non-aqueous media have been considered in these studies. Applications include high voltage insulating dielectrics, thermally conductive/electrically insulating films, adherent lubricating films, uniform photoresist films, glass coatings, and fissile uranium oxide/carbon composite films for studies of nuclear powered lasers. More recently, we have become interested in the beneficial environmental aspects of being able to provide protective polymer coatings which reduce or minimize the use of organic solvents required by traditional spray coat processes. Important practical factors which relate to film uniformity, adhesion, and composition are related to unique coating or plating capabilities and applications. 6 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Sharp, D.J.
Partner: UNT Libraries Government Documents Department