Electret state of butadiene-styrene copolymers

Abstract

Thermally stimulated depolarization currents (TSDC) in the range of 120-350 K are exploited to study triblock and statistical styrene-butadiene copolymers. TSDC peaks occur at the butadiene phase glass transition, due to the reorientation of butadiene dipolar groups. The peak is accounted for by a distribution of relaxation times. In block copolymers the TSDC signal is monitored at the butadiene phase transition temperature even if the sample is not previously polarized. Ordering effects induced by the sample preparation are discussed.<>