화학공학소재연구정보센터
Journal of Polymer Science Part B: Polymer Physics, Vol.39, No.3, 286-299, 2001
Relaxation behavior of acrylate and methacrylate polymers containing dioxacyclopentane rings in the side chains
The synthesis of poly[(2,2-dimethyl-1,3-dioxolan-4-yl) methyl acrylate] (PACCA) and poly[(2,2-dimethyl-1,3-dioxolan-4-yl) methyl methacrylate] (PMCGA) is reported. Both polymers present dielectric and mechanical beta subglass absorptions at -128 and -115 degreesC, respectively, at 1 Hz, followed by ostensible glass-rubber or or relaxations centered in the vicinity of 0 and 67 degreesC, respectively, at the same frequency. The values of the activation energy of both the mechanical and dielectric beta absorptions lie in the vicinity of 10 kcal mol 1. The critical interpretation of the relaxation behavior of PMCGA suggests that dipolar intramolecular correlations play a dominant role in the response of the polymer to an electric field. The subglass relaxations of PACGA and PMCGA are further compared with the relaxation behavior of poly(1,3-dioxane acrylate), poly(1,3-dioxane methacrylate), and other polymers in the glassy state. The strong conductive processes observed in PMCGA at low frequencies and high temperatures were studied under the assumption that that these processes arise from Maxwell-Wagner-Sillars effects occurring in the bulk combined with Nernst-Planckian electrodynamic effects caused by interfacial polarization in the films. (C) 2000 John Wiley & Sons, Inc.