A broad spectrum analysis of the dielectric properties of poly(2-hydroxyethyl methacrylate)

The dielectric permittivity, epsilon ', and the loss factor, epsilon '', of dry poly(2-hydroxyethyl methacrylate) were measured using a dielectric analyzer in the frequency range of 0.1 Hz to 100 kHz and between the temperature range of - 150 to 275 degrees C. The dielectric response of the sub-T-g gamma transition of PHEMA has been widely studied before but little to no DEA data above 50 degrees C is present in the literature. In this study the dielectric spectrum is presented up to and above the T-g. The electric modulus formalism is used to reveal the gamma, beta, alpha and conductivity relaxations. The apparent activation energies for the relaxations are presented. (c) 2005 Elsevier Ltd. All rights reserved.