712 Matching Results

Search Results

Advanced search parameters have been applied.

TRANSPARENT COLD-SHOCK-RESISTANT EPOXY CASTING RESIN

Description: The development of a transparent cold-shook-resistant epoxy casting resin is discussed. Physical and electrical properties are presented. A simple inexpensive test method for determining cold-shock-resistance is described. (authl
Date: April 1, 1960
Creator: Carroll, B. & Smatana, J.
Partner: UNT Libraries Government Documents Department

The properties of three cast polyester resins of Sierracin 212, 212A, and 250A

Description: From Summary: "Physical properties of samples of three cast polyester resins known as Sierracin resins were investigated. Tests were made to determine specific gravity, index of refraction, Rockwell hardness, Tukon indentation hardness, effect of exposure to accelerated and outdoor weathering, Munsell color, resistance to accelerated service tests, crazing resistance under stress, flexural strength, Izod impact strength, and Taber abrasion resistance. Tables of the values obtained for these physical properties are included in the report."
Date: April 23, 1951
Creator: Kline, G. M.
Partner: UNT Libraries Government Documents Department

Synthetic resins in aircraft construction - their composition, properties, present state of development and application to light structures

Description: This report gives a brief review of the properties that have been attained with the synthetic materials with which we are at present familiar. Results of investigations are presented as well as possibilities for construction applications. Endurance strength and bonding tests are also presented.
Date: November 1937
Creator: Riechers, K.
Partner: UNT Libraries Government Documents Department

A Comparative Study of Three Epoxy Resins in the Industrial Arts Laboratory

Description: This study was made to determine the advantages of the use of epoxy resins in the industrial arts laboratory. The purpose of this study was to determine the feasibility of using epoxy resins as a wood adhesive. Data was gathered from texts, periodicals, and unpublished data. Tests were conducted using epoxy samples acquired from three epoxy manufacturers on three different woods and joints. The study discusses the advantages and disadvantages of using epoxy resins as a wood adhesive and the material and equipment necessary for the use of epoxy resins. Strength tests were performed on the joints adhered with epoxy and on joints adhered with white glue. A hand operated high tensile strength machine was used to conduct the tests. Epoxy Resins were found, in most cases, to give a more durable bond than white glue. Further studies should be made using epoxy resins as adhesives for metal, glass, plastic, and other materials used in the industrial arts laboratory.
Date: May 1974
Creator: Yeatts, Fred Henry
Partner: UNT Libraries

Plastics as structural materials for aircraft

Description: The purpose here is to consider the mechanical characteristics of reinforced phenol-formaldehyde resin as related to its use as structural material for aircraft. Data and graphs that have appeared in the literature are reproduced to illustrate the comparative behavior of plastics and materials commonly used in aircraft construction. Materials are characterized as to density, static strength, modulus of elasticity, resistance to long-time loading, strength under repeated impact, energy absorption, corrosion resistance, and ease of fabrication.
Date: December 1937
Creator: Kline, G. M.
Partner: UNT Libraries Government Documents Department

VARIABLY CURING RESINS FOR MOUNTING METALLOGRAPHIC SAMPLES

Description: In the past, heat-and-pressure-curing resins have been used almost exclusively as mounting materials for metallographic samples. Now, however, certain polyester resins, which are curable at room temperature, are equally as good for this purpose, and with their versatility they adapt readily to a variety of mounting conditions. A study of the epoxies and polyesters was made to determine which type of resin would satisfy the desirable properties of a metallographic mount. Four polyester resins were selected and investigated intensively to ascertain the variables associated with their curing processes. The results are compared with the standard thermosetting mounting material, Bakelite. (auth)
Date: September 1, 1963
Creator: Kruger, O.L.; Hughes, J.P. & Schmitz, F.J.
Partner: UNT Libraries Government Documents Department

Cure Kinetics and Processing Parameters of Neat and Reinforced High Performance Epoxy Resins: Evaluation of Techniques

Description: Kinetic equation parameters for the curing reaction of a commercial glass fiber reinforced high performance epoxy prepreg composed of the tetrafunctional epoxy tetraglycidyl 4,4-diaminodiphenyl methane (TGDDM), the tetrafunctional amine curing agent 4,4’-diaminodiphenylsulfone (DDS) and an ionic initiator/accelerator, are determined by various thermal analysis techniques and the results compared. The reaction is monitored by heat generated determined by differential scanning calorimetry (DSC). The changes in physical properties indicating increasing conversion are followed by shifts in glass transition temperature determined by DSC and temperature-modulated DSC (TMDSC), thermomechanical (TMA) and dynamic mechanical (DMA) analysis and thermally stimulated depolarization (TSD). Changes in viscosity, also indicative of degree of conversion, are monitored by DMA. Thermal stability as a function of degree of cure is monitored by thermogravimetric analysis (TGA). The parameters of the general kinetic equations, including activation energy and rate constant, are explained and used to compare results of various techniques. The utilities of the kinetic descriptions are demonstrated in the construction of a useful time-temperature-transformation (TTT) diagram for rapid determination of processing parameters in the processing of prepregs. Copyright is held by the author, unless otherwise noted. All rights reserved. Files: Thesis.pdf Special Conditions
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: December 1999
Creator: Bilyeu, Bryan
Partner: UNT Libraries

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

Description: Resin denitration via anion-exchange is an implementable process that can effectively mitigate the hazards associated with stored resins in which the bulk of the nitrate consists of an "exchangeable nitrate" ionically bound to the cationic sites of the anion-exchange resins. Salicylate has been selected as the exchange anion of choice because of its superior selectivity for the Rocky Flats resins and its unique potential for comprehensive recovery and recycle. This report outlines a single recommended resin denigration procedure that is reasonably independent of the resin composition and the current stored form. This procedure is not optimized but rather seeks to `over-treat' the resins so that a single procedure works for the variety of stored resins. The recommended treatment with sodium salicylate reduces resins by 95-99+% the measured exothermic behavior of the ion-exchange.
Date: December 1, 1998
Creator: Espinoza, Jacob; Barr, Mary & Smith, Wayne
Partner: UNT Libraries Government Documents Department

Characterization of Cure Kinetics and Physical Properties of a High Performance, Glass Fiber-Reinforced Epoxy Prepreg and a Novel Fluorine-Modified, Amine-Cured Commercial Epoxy.

Description: Kinetic equation parameters for the curing reaction of a commercial glass fiber reinforced high performance epoxy prepreg composed of the tetrafunctional epoxy tetraglycidyl 4,4-diaminodiphenyl methane (TGDDM), the tetrafunctional amine curing agent 4,4'-diaminodiphenylsulfone (DDS) and an ionic initiator/accelerator, are determined by various thermal analysis techniques and the results compared. The reaction is monitored by heat generated determined by differential scanning calorimetry (DSC) and by high speed DSC when the reaction rate is high. The changes in physical properties indicating increasing conversion are followed by shifts in glass transition temperature determined by DSC, temperature-modulated DSC (TMDSC), step scan DSC and high speed DSC, thermomechanical (TMA) and dynamic mechanical (DMA) analysis and thermally stimulated depolarization (TSD). Changes in viscosity, also indicative of degree of conversion, are monitored by DMA. Thermal stability as a function of degree of cure is monitored by thermogravimetric analysis (TGA). The parameters of the general kinetic equations, including activation energy and rate constant, are explained and used to compare results of various techniques. The utilities of the kinetic descriptions are demonstrated in the construction of a useful time-temperature-transformation (TTT) diagram and a continuous heating transformation (CHT) diagram for rapid determination of processing parameters in the processing of prepregs. Shrinkage due to both resin consolidation and fiber rearrangement is measured as the linear expansion of the piston on a quartz dilatometry cell using TMA. The shrinkage of prepregs was determined to depend on the curing temperature, pressure applied and the fiber orientation. Chemical modification of an epoxy was done by mixing a fluorinated aromatic amine (aniline) with a standard aliphatic amine as a curing agent for a commercial Diglycidylether of Bisphenol-A (DGEBA) epoxy. The resulting cured network was tested for wear resistance using tribological techniques. Of the six anilines, 3-fluoroaniline and 4-fluoroaniline were determined to have lower wear than the ...
Date: December 2003
Creator: Bilyeu, Bryan
Partner: UNT Libraries

A Note on the Use of Ion Exchange Resins for the Purification of Urinary Purines, Kynurenic Acid, and Coproporphyrin: (Preliminary Report)

Description: Abstract: "Preliminary studies are reported on the use of the ion exchange resins for the adsorptions of purines, uracil, nucleotides, kynurenic acid, and coproporphyrin. Adenine and guanine are adsorbed on IR-100 resin from neutral solution and eluted by HCl. Kynurenic acid and coproporphyrin are adsorbed from neutral solution on IR-4 resin and eluted by HCl. Coproporphyrin is strongly adsorbed on IR-100 resin from either acid, alkaline, or neutral solution. Kynurenic acid is poorly adsorbed on IR-100 resin from neutral aqueous solution. The preliminary application of these procedures to the spectro-photometric study of urine is described."
Date: July 1946
Creator: Schwartz, Samuel.; Wattenberg, Lee W. & Zagaria, Ralph
Partner: UNT Libraries Government Documents Department

Curing of Resin-Wood Combinations by High-Frequency Heating

Description: Note presenting a summary of the results of an investigation of the curing of resin-wood combinations by high-frequency heating. The physical facts pertinent to high-frequency heating are introduced and the procedure is described for measuring dielectric constant and loss from 1 to 100 megacycles. The results indicated that the high-frequency heating process is feasible, flexible, and timesaving.
Date: December 1942
Creator: von Hippel, Arthur R. & Dietz, A. G. H.
Partner: UNT Libraries Government Documents Department

EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM SPHERICAL RESORCINOL-FORMALDEHYDE RESIN

Description: Ion Exchange column loading and elution of cesium from spherical resorcinol-formaldehyde resin have been conducted for two potential non-acid eluants -(NH{sub 4}){sub 2}CO{sub 3} and CH{sub 3}COONH{sub 4}. The results revealed encouraging cesium elution performance. 100% elution was achieved in at most 22 hours ({approx}28 bed volumes) of elution. Elution performance was fairly high at 6 hours ({approx}8 bed volumes) of elution for some of the eluants and also practically comparable to the benchmark acid eluant (HNO{sub 3}). Hence, it is quite possible 100% percent elution will be closer to the 6th hour than the 22nd hour. Elution is generally enhanced by increasing the concentration and pH of the eluants, and combining the eluants.
Date: October 23, 2011
Creator: Adu-Wusu, K.; Nash, C. & Pennebaker, F.
Partner: UNT Libraries Government Documents Department

Rapid Separation of Heavy Rare-Earth Elements

Description: The U.S. Bureau of Mines investigated the separation of heavy rare-earth elements (REE) in an ion-exchange process. An ion-exchange column consisting of two sections, a loading section and a separation section, provides high levels of REE loading and good REE separation with an expected processing cycle of less than a month, while current ion-exchange technology requires more than 5 months. A different resin is used in each section: sulfonic resin in the loading section and iminodiacetic resin in the separation section. The separation section is further divided into two segments: the first conditioned with NH4 and the second with acid. Erbium is loaded onto both segments of the separation column as a retaining ion. Bands of mixed REE eluting between separated bands of pure REE were recycled directly to the column. Without mixed-band recycle, over 80% of the REE eluted from the column was separated into fractions with 99% purity of each element; with such recycle, the percentage of separated elements can be increased to around 90%.
Date: 1995
Creator: Moore, B. W.; Froisland, L. J. & Petersen, A. E.
Partner: UNT Libraries Government Documents Department

Quantitative prediction of stresses during thermoset cure

Description: Two thin-walled Al tubes were filled with epoxy which were cured isothermally; one tube was instrumented with strain gauges, and the other with thermocouples. Finite element codes were used. Predicted and measured centerline hoop strains are shown; predictions and measurements agree. This is being applied to encapsulated components.
Date: July 1, 1996
Creator: Adolf, D.; Chambers, B. & Burchett, S.
Partner: UNT Libraries Government Documents Department

Test procedures for polyester immobilized salt-containing surrogate mixed wastes

Description: These test procedures are written to meet the procedural needs of the Test Plan for immobilization of salt containing surrogate mixed waste using polymer resins, HNF-SD-RE-TP-026 and to ensure adequacy of conduct and collection of samples and data. This testing will demonstrate the use of four different polyester vinyl ester resins in the solidification of surrogate liquid and dry wastes, similar to some mixed wastes generated by DOE operations.
Date: July 18, 1997
Creator: Biyani, R.K. & Hendrickson, D.W.
Partner: UNT Libraries Government Documents Department

Characterization and Process Development of Cyanate Ester Resin Composites

Description: Cyanate ester resins offer advantages as composite matrices because of their high thermal stability, low outgassing, low water absorption, and radiation resistance. This paper describes the results of a processing study to develop a high-strength hoop-wound composite by the wet-filament winding method using Toray TI 000G carbon fiber and YLA RS- 14A cyanate ester resin as the constituent materials. The study shows that the cyanate ester resin has a broad process envelope but that an inert-atmosphere cure is essential for obtaining optimum resin and composite properties. Minimizing moisture exposure prior to and during cure is also crucial as it affects the glass transition temperature of the resin and composite. Composite cylinders wound and cured with these methods yielded excellent ring tensile strengths both at room and elevated temperature. A summary of the measured mechanical and thermal property data for these composites is presented. Potential applications for these materials include flywheeI energy storage systems for space and satellite structures.
Date: May 23, 1999
Creator: Frame, B.J.
Partner: UNT Libraries Government Documents Department

Epoxy Foam Encapsulants: Processing and Dielectric Characterization

Description: The dielectric performance of epoxy foams was investigated to determine if such materials might provide advantages over more standard polyurethane foams in the encapsulation of electronic assemblies. Comparisons of the dielectric characteristics of epoxy and urethane encapsulant foams found no significant differences between the two resin types and no significant difference between as-molded and machined foams. This study specifically evaluated the formulation and processing of epoxy foams using simple methylhydrosiloxanes as the flowing agent and compared the dielectric performance of those to urethane foams of similar density.
Date: January 1, 1999
Creator: Domeier, Linda & Hunter, Marion
Partner: UNT Libraries Government Documents Department