Relaxational study of poly(2-chlorocyclohexyl methacrylate) by thermally stimulated current, dielectric, and dynamic mechanical spectroscopy

A comparative study of the mechanical and dielectric relaxation spectra of poly(2-chlorocyclohexyl methacrylate) (P2CCM) is reported. Two clear relaxa tional zones are found. The spectra present a moderate subglass gamma absor ption, followed in increasing temperature order by a prominent a glass-rubb er relaxation process. The last peak is not clearly observed in dielectric measurements due to conductivity effects which overlap the loss permittivit y spectrum. Moreover, evidence of remnant mechanical as well as dielectric activity is observed near room temperature. This phenomenon has already bee n observed in poly(2-chlorocyclohexyl acrylate) (P2CCA). To describe in a s uitable way these results, a deconvolution method has been proposed to get information about the relaxational behavior of this polymer. A more detaile d analysis about the third relaxation called beta, between alpha and gamma relaxations, has been achieved by using the thermally stimulated depolariza tion current technique (TSDC). Special attention was devoted to the analysi s of the molecular motion that produces dielectric and mechanical activity in glassy P2CCM as well as to link the elementary TSDC to the ac dielectric spectra. A comparative study of P2CCM and P2CCA is also reported.