Dielectric Relaxation Studies of Bisphenol A Polyarylates

Abstract

The dielectric relaxation characteristics of two polyarylates based on Bisphenol A and isophthalic (ISO) and terephthalic (TA) acids (75/25 and 50/50) have been examined across both the glass-rubber (α) and sub-glass (β) relaxations. The higher isophtalate content in the 75/25 ISO/TA polymer resulred in a lower α relaxation temperature as compared to the 50/50 sample and a stronger relaxation response; this latter result is consistent witha lower degree of dipolar cancellation in the 75/25 material owing to its lower TA content