Description of thermal and mechanical properties of drawn polymers over a wide temperature range

Temperature dependencies of the thermal expansion coefficient for segments of macromolecular helices, α( T ), were obtained for polymers by infrared (IR) spectroscopy. It was shown that the α( T ) are complicated (nonlinear) over a wide temperature range. Wunderlich and Bauer's idea concerning “freezing out” of normal vibrations of polymer chains was used to describe them. It was shown that the substitution of the classical rather than quantum statistics for both torsional and bending vibrational modes of macromolecules causes complications in α( T ). Mechanical properties of drawn linear polymers are connected with the thermal expansion. Therefore, such an approach may be used to describe the temperature dependence of Young's modulus and failure strength for drawn polymers in the range from cryogenic to melting temperatures.