Thermally Stimulated Discharge Currents of Poly(acrylonitrile-co-acrylic Acid)-Polypyrrole Composites

Abstract

Thermally Stimulated Discharge Currents, one of the oldest destructive method widely used for studying the mechanisms of polarization and depolarization within the dielectrics was employed for determining information related to trapped and/or detrapped charges and activation energy (Ea) within P(AN-co-AA)-PPy composite films. Two peaks or two relaxation regions could be noticed on the TSDC spectra for each material under test: one at a temperature around 323.15K (50°C), attributed to decomposition due to DMF removal as presented in our previous studies, and a second one at 363.15K (90°C), attributed to glass transition temperature. An increased of detrapped charges was observed when the PPy quantity within the P(AN-co-AA) matrix was increased. The same time, both relaxations appeared at very close temperatures for all three samples under test. Complementary measurements for an in-depth electrical analysis were performed with the help of Broadband Dielectric Spectroscopy (BDS), while further information regarding conductive composites structures was obtained through FTIR-ATR analysis.