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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

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 Data was gathered from texts, periodicals, and unpublished data.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

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

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

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
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Date: December 1999
Creator: Bilyeu, Bryan
Partner: UNT Libraries

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

Compressive Creep Response of T1000G/RS-14 Graphite/Polycyanate Composite Materials

Description: The response of a T1000G/RS-14 graphite/polycyanate composite material system to transverse compressive loads is quantified via experimentation. The primary objective of the work was to quantify the effects of process environment and test environment on the T1000G/RS-14 compressive creep response. Tests were conducted on both the neat resin and the composite material system. In addition to the creep tests, static compressive strength tests were conducted to define the stress-strain response. The creep behavior for the RS-14 resin was quantified by conducting a series of tests to study the effects of different process environments (air and nitrogen), different cure temperatures, and different test environments (air and vacuum). The combined effect on the RS-14 resin compressive creep of processing in nitrogen and testing under vacuum versus processing in air and testing in air was a 47% decrease in the creep strain after 2177 hr. The test environment appeared to have a greater effect on the resin creep than the process environment. Following the conclusion of the resin creep tests, composite transverse compressive creep tests were conducted. The composite creep test cylinder was post-cured in a nitrogen environment prior to machining test specimens and all tests were conducted in a vacuum environment. The series of tests investigated the effects of initial stress level and test temperature on the creep behavior. At the end of the 2000-hr tests at 275{degrees}F on specimens stressed at 10,000 psi, the nitrogen-processed and vacuum-tested conditions reduced the composite transverse compressive creep strain by 19% compared to processing in air and testing in air. The effects of process and test environment on the creep behavior are not as great for the composite system as they were for the neat resin, primarily because of the low resin content in the composite material system. At the 275{degrees}F test temperature there was ...
Date: January 1, 1998
Creator: Starbuck, J.M.
Partner: UNT Libraries Government Documents Department

On the Mechanical Response of Chopped Glass/Urethane Resin Composite: Data and Model

Description: This report presents data on the creep response of a polymeric composite that is a candidate material for automotive applications. The above data were used to establish the basis for the mechanical characterization of the material's response over a wide range of stresses and temperatures, as well as under cyclic loading and due to exposure to distilled water. A constitutive model based upon fundamental principles of irreversible thermodynamics and continuum mechanics was employed to encompass the above mentioned database and to predict the response under more complex inputs. These latter tests verified the validity of the model.
Date: November 1999
Creator: Elahi, M. & Weitsman, Y. J.
Partner: UNT Libraries Government Documents Department

Evaluation of Two Solid Forms for Shipping Enriched Uranium

Description: Because of the possibility of an enriched uranium spill in transit, a program has been initiated to develop safer methods of shipment. This report compares uranium on resin with conversion to unpurified UO3, and provides information needed to judge the relative merits of the processes to produce these two solid forms.
Date: August 26, 2002
Creator: Wilds, G.W.
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

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

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

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 and Composite

Description: 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.
Date: March 1998
Creator: Frame, B. J.
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

Enhancements of Mechanical, Thermal Stability, and Tribological Properties by Addition of Functionalized Reduced Graphene Oxide in Epoxy

Description: The effects of octadecylamine-functionalized reduced graphene oxide (FRGO) on the frictional and wear properties of diglycidylether of bisphenol-A (DGEBA) epoxy are studied using a pin-on-disk tribometer. It was observed that the addition of FRGO significantly improves the tribological, mechanical, and thermal properties of epoxy matrix. Graphene oxide (GO) was functionalized with octadecylamine (ODA), and then reduction of oxygen-containing functional groups was carried out using hydrazine monohydrate. The Raman and x-ray photoelectron spectroscopy studies confirm significant reduction in oxygen-containing functional groups and formation of ODA functionalized reduced GO. The nanocomposites are prepared by adding 0.1, 0.2, 0.5 and 1.0 wt % of FRGO to the epoxy. The addition of FRGO increases by more than an order of magnitude the sliding distance during which the dynamic friction is ≤ 0.1. After this distance, the friction sharply increases to the range of 0.4 - 0.5. We explain the increase in sliding distance during which the friction is low by formation of a transfer film from the nanocomposite to the counterface. The wear rates in the low and high friction regimes are approximately 1.5 x 10-4 mm3/N·m and 5.5 x 10-4 mm3/N·m, respectively. The nanocomposites exhibit a 74 % increase in Young’s modulus with 0.5 wt. % of FRGO, and an increase in glass transition and thermal degradation temperatures.
Date: August 2014
Creator: Shah, Rakesh K.
Partner: UNT Libraries

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

DEVELOPMENT AND MANUFACTURE OF COST EFFECTIVE COMPOSITE DRILL PIPE

Description: This technical report presents the engineering research, process development and data accomplishments that have transpired to date in support of the development of Cost Effective Composite Drill Pipe (CDP). The report presents progress made from October 1, 2003 through September 30, 2004 and contains the following discussions: (1) Direct Electrical Connection for Rotary Shoulder Tool Joints; (2) Conductors for inclusion in the pipe wall (ER/DW-CDP); (3) Qualify fibers from Zoltek; (4) Qualify resin from Bakelite; (5) First commercial order for SR-CDP from Integrated Directional Resources (SR-CDP); and (6) Preparation of papers for publication and conference presentations.
Date: March 18, 2005
Creator: Leslie, James C.; II, James C. Leslie; Truong, Lee; Heard, James T. & Manekas, Peter
Partner: UNT Libraries Government Documents Department

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

Description: 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
Date: April 21, 2004
Creator: WOol, Dr. Richard; Sun, Dr. X. Susan & Chapas, Rich
Partner: UNT Libraries Government Documents Department