The Crystallization Effect of Thermal Relaxation of Dipoles on Poly （Ethylene Terephthalate）

A series of PET films with different crystallinity were obtained by annealing at 110℃ . The behavior of thermal relaxation of dipoles of crystallized PET had been studied with method of TSC. The α peak of short-circuit thermally stimulated current was shifted to higher temperature when the crystallinity was increased. The activation energy of thermal relaxation of dipoles for main-chain segmental motion in amorphous region was decreased linearly and the time constant of dipolar thermal relaxation was increased exponentially with increasing of crystallinity.