Comparative study of methyl position effect in poly(methyl) cyclohexyl methacrylates by TSDC and TW

A comparative study of the effect of the position of the methyl group in the cyclohexyl ring in poly (2-methy) cyclohexyl methacrylate (P2MCHM), poly (3-methyl) cyclohexyl methacrylate (P3MCHM) and poly(4-methyl) cyclohexyl methacrylate (P4MCHM) has been carried out by thermally stimulated depolarization currents (TSDC), and thermal windows (TW) measurements. In the TSDC global spectra we appreciate the evolution of the subglass and glass transition absorptions as a function of the position of the methyl group. For each sample fractional polarization is used to describe the fine structure of these complex spectra. By fitting the experimental data to standard models, the kinetic parameters of the relaxations observed have been evaluated. In the glassy state, the complex dielectric permittivity in the frequency domain was calculated at several temperatures from elementary- peaks obtained by partial TSDC curves.