ReSource, Volume 14, 2002-03

ReSource, Volume 14, 2002-03

Date: 2003
Creator: University of North Texas
Description: ReSource magazine includes articles and notes about research at University of North Texas in various academic fields.
Contributing Partner: University Relations, Communications & Marketing department for UNT
ReSource, Volume 13, 2001

ReSource, Volume 13, 2001

Date: 2001
Creator: University of North Texas
Description: ReSource magazine includes articles and notes about research at University of North Texas in various academic fields.
Contributing Partner: University Relations, Communications & Marketing department for UNT
Electric Field Induced Phase Transitions in Polymers: A Novel Mechanism for High Speed Energy Storage

Electric Field Induced Phase Transitions in Polymers: A Novel Mechanism for High Speed Energy Storage

Date: February 23, 2012
Creator: Ranjan, Vivek; Buongiorno Nardelli, Marco & Bernholc, Jerry
Description: This article discusses electric field induced phase transitions in polymers.
Contributing Partner: UNT College of Arts and Sciences
Synthesis and Study of Engineered Heterogenous Polymer Gels

Synthesis and Study of Engineered Heterogenous Polymer Gels

Date: August 1998
Creator: Chen, Yuanye
Description: This dissertation studies physical properties and technological applications of engineered heterogenous polymer gels. Such gels are synthesized based on modulation of gel chemical nature in space. The shape memory gels have been developed in this study by using the modulated gel technology. At room temperature, they form a straight line. As the temperature is increased, they spontaneously bend or curl into a predetermined shape such as a letter of the alphabet, a numerical number, a spiral, a square, or a fish. The shape changes are reversible. The heterogenous structures have been also obtained on the gel surface. The central idea is to cover a dehydrated gel surface with a patterned mask, then to sputter-deposit a gold film onto it. After removing the mask, a gold pattern is left on the gel surface. Periodical surface array can serve as gratings to diffract light. The grating constant can be continuously changed by the external environmental stimuli such as temperature and electric field. Several applications of gels with periodic surface arrays as sensors for measuring gel swelling ratio, internal strain under an uniaxial stress, and shear modulus have been demonstrated. The porous NIPA gels have been synthesized by suspension technique. Microstructures of newly ...
Contributing Partner: UNT Libraries
Development of a Simplified Fracture Toughness Tool for Polymers

Development of a Simplified Fracture Toughness Tool for Polymers

Date: August 1997
Creator: Marnock, Patrick J. (Patrick Joseph)
Description: This thesis presents research toward the development of a simple inexpensive fracture toughness tool for polymeric materials. Experiments were conducted to test the specimen configuration and the fracture toughness tool against an established ASTM standard for polymer fracture toughness, D5045, and a commonly used four-point bend method. The materials used in this study were polycarbonate and high density polyethylene. Reductions in both the production time and the variability resulting from the preparation of the specimens were addressed through the use of specially designed fixtures. The effects from the razor cut depths used in the chevron notch were compared to the fracture toughness values obtained in order to determine the effect upon the validity of the fracture toughness.
Contributing Partner: UNT Libraries
Monodisperse Thermo-Responsive Microgels of Poly(Ethylene Glycol) Analogue-Based Biopolymers, their Manufacture, and their Applications

Monodisperse Thermo-Responsive Microgels of Poly(Ethylene Glycol) Analogue-Based Biopolymers, their Manufacture, and their Applications

Date: July 14, 2009
Creator: Hu, Zhibing; Cai, Tong; Chi, Chenglin & Marquez, Manuel
Description: Patent relating to monodisperse thermo-responsive microgels of poly(ethylene glycol) analogue-based biopolymers, their manufacture, and their applications.
Contributing Partner: UNT College of Arts and Sciences
Determination of Wear in Polymers Using Multiple Scratch Test.

Determination of Wear in Polymers Using Multiple Scratch Test.

Date: August 2004
Creator: Damarla, Gowrisankar
Description: Wear is an important phenomenon that occurs in all the polymer applications in one form or the other. However, important links between materials properties and wear remain illusive. Thus optimization of material properties requires proper understanding of polymer properties. Studies to date have typically lacked systematic approach to all polymers and wear test developed are specific to some polymer classes. In this thesis, different classes of polymers are selected and an attempt is made to use multiple scratch test to define wear and to create a universal test procedure that can be employed to most of the polymers. In each of the materials studied, the scratch penetration depth s reaches a constant value after certain number of scratches depending upon the polymer and its properties. Variations in test parameters like load and speed are also studied in detail to understand the behavior of polymers and under different conditions. Apart from polystyrene, all the other polymers studied under multiple scratch test reached asymptotes at different scratch numbers.
Contributing Partner: UNT Libraries
Plasma Treated Multi-Walled Carbon Nanotubes (MWCNTs) for Epoxy Nanocomposites

Plasma Treated Multi-Walled Carbon Nanotubes (MWCNTs) for Epoxy Nanocomposites

Date: December 19, 2011
Creator: Ritts, Andrew C.; Yu, Qingsong; Li, Hao; Lombardo, Stephen J.; Han, Xu; Xia, Zhenhai et al.
Description: This article describes the depositing of plasma nanocoating of allylamine on the surfaces of multi-walled carbon nanotubes to provide desirable functionalities and thus to tailor the surface characteristics of multi-walled carbon nanotubes for improved dispersion and interfacial adhesion in epoxy matrices.
Contributing Partner: UNT College of Engineering
Compostable Soy-Based Polyurethane Foam with Kenaf Core Modifiers

Compostable Soy-Based Polyurethane Foam with Kenaf Core Modifiers

Access: Use of this item is restricted to the UNT Community.
Date: August 2016
Creator: Hoyt, Zachary
Description: Building waste and disposable packaging are a major component in today's landfills. Most of these are structural or thermally insulative polymer foams that do not degrade over a long period of time. Currently, there is a push to replace these foams with thermoplastic or biodegradable foams that can either be recycled or composted. We propose the use of compostable soy-based polyurethane foams (PU) with kenaf core modifiers that will offer the desired properties with the ability to choose responsible end-of-life decisions. The effect of fillers is a critical parameter in investigating the thermal and mechanical properties along with its effect on biodegradability. In this work, foams with 5%, 10%, and 15% kenaf core content were created. Two manufacturing approaches were used: the free foaming used by spray techniques and the constrained expansion complementary to a mold cavity. Structure-property relations were examined using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermal conductivity, compression values, scanning electron microscopy (SEM), x-ray micro-computed tomography (micro-CT), and automated multiunit composting system (AMCS). The results show that mechanical properties are reduced with the introduction of kenaf core reinforcement while thermal conductivity and biodegradability display a noticeable improvement. This shows that in application properties can be ...
Contributing Partner: UNT Libraries
A Compilation and Evaluation of Mechanical, Thermal, and Electrical Properties of Selected Polymers

A Compilation and Evaluation of Mechanical, Thermal, and Electrical Properties of Selected Polymers

Date: September 1973
Creator: Schramm, R. E.; Clark, A. F. & Reed, R. P.
Description: From Abstract: "This compilation abstracts original experimental data on the mechanical, thermal, and electrical properties of six commercially available polymers. The data are also summarized and a brief description of each polymer is included."
Contributing Partner: UNT Libraries Government Documents Department