Dielectric and mechanical-dynamical studies on poly(cyclohexyl methacrylate)

The relaxation processes in poly(cyclohexyl methacrylate) have been studied by transient and dynamic dielectric means as well as by viscoelastic techniques. The study embraces also the effect of the thermal treatment on the α and β relaxations. The α relaxation has been fitted into the empirical model of Havriliak and Negami, and the functional relation between the mean relaxation times and the temperature has been adjusted to the equation of Vogel. The β relaxation is strongly hindered, so it is scarcely perceivable. The secondary γ relaxation was studied mainly by dielectric means. Its apparent activation energy does not depend on the temperature and amounts to 11.2 ± 0.2 kcal mol^?1. It allows an application of the time-temperature superposition principle and its behaviour is thermorheologically simple. A δ relaxation with a temperature-independent apparent activation energy of 8.5 kcal mol^?1 has been obtained