Volume recovery of glassy poly‐α‐methylstyrene

Abstract

A method for evaluating the relaxation time as a function of both temperature and volume from volume contraction experiments, as proposed by Kovacs, was experimentally examined by using monodisperse poly‐α‐methylstyrene samples of various molecular weights and blends. It was concluded that his theory can be successfully applied to the present experimental data, though his two different approximations give somewhat different values of the shift factor for the time‐temperature superposition of volume contraction data. A difference was observed between the temperature dependence of the shift factor of monodisperse polymers and that of blends.