The effect of uniaxial orientation on the dielectric relaxation behavior of α‐PVDF

Abstract

Abstract α‐crystalline phase poly(vinylidene fluoride) (PVDF) film was oriented uniaxially at different draw ratios. Morphological effects of orientation were investigated by X‐ray diffraction and differential scanning calorimetry (DSC) measurements on the oriented samples. The dielectric loss factor was measured from 100 Hz to 1 MHz range between 80 and 400 K as a function of frequency and temperature. While the activation energy of the α‐relaxation transition was not affected by the orientation, it was observed that there is a linear increase in the activation energy of the β‐relaxation transition with draw ratio. The relaxation time of the β‐relaxation transition was more affected by the orientation process at lower temperatures. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008