glass transition temperature

Thermophysical Properties of Composite Metal-Filled Copolymers of Polyvinylpyrrolidone

The effect of the presence of finely dispersed metal fillers of various natures (Zn, Co, Ni) on the thermophysical characteristics (Vick heat resistance, glass transition temperature) of polyvinylpyrrolidone block copolymers with 2-hydroxyethylmethacrylate was studied. It was found that the heat resistance of the obtained composites significantly exceeds the heat resistance of unfilled copolymers and is in the range of 360-395K, depending on the nature and content of the metal filler.

Correlation of the glass transition temperature and average energetic connectivity in network chalcogenide glasses

A correlation ratio between a glass transition temperature Tg and average bond energy E (obtained for chalcogenide glasses in L. Tichý & H. Tichá [J. Non-Cryst. Solids, 189, 1995]) was critically analyzed in this paper. As a result, this ratio was shown to have been obtained using incorrect calculations of the average bond energy E through inappropriate application of different averaging procedures for different terms of this parameter and, therefore, it cannot be used in practice.

Properties of Multifunctional Polymers – Carbon Black Composite Vapor Detectors

In this work the electrical properties of vapor detectors, formed from composites of conductive carbon-black and insulating organic multifunctional polymers having metal ions complexing ability, were investigated. The new composites are tailored to produce increased sensitivity toward specific classes of analyte vapors. Resonant frequency shift of a Quartz Crystal Microbalance (QCM) and dc resistance measurements have been also performed simultaneously on polymer-carbon black composite materials.

Role of the Structure and Composition of Macromolecule Chain in Chemical Plasticization of Polymers

The correlation between the parameters of chemically plasticized polar polymers (glass transition temperature, solubility parameter, cohesive energy, polarizability, modulus of elasticity in shear) with polarity and van der Waals volume of macromolecule link was investigated. It was shown that the chemical plasticization of PVAc and PVME by the alkylated polar groups replacement in weakly polar methyl group is not associated with the parameters of isolated macromolecule and is mainly determined by the intermolecular interaction.