Understanding Structural Evolution of α- (γ-) Poly(vinylidene fluoride) during High Temperature Deformation by in-situ Synchrotron X-ray

• 1、College of Polymer Science and Engineering, Sichuan University, Chengdu 610065

Abstract：It is a general and important method to get the electroactive β phase of poly(vinylidene fluoride) by stretching, that is why the α-β transformation during stretching is widely investigated in the past several decades, however, the stretching of another important phase of PVDF (i.e. γ phase) is rarely concerned which may be due to the difficulty for obtaining pure γ phase . In this work, the deformation and transformation behaviors of pure α and γ PVDF under high temperature are investigated by in-situ synchrotron X-ray diffraction and scattering. It is clear that under the temperature which oriented α phase is dominated after stretching, high amount of β phase could be obtained by stretching γ phase. It seems that γ phase could transform to β phase under lower strain. This work extends our understanding about the polymorphism transformation in PVDF, as well as the proper conditions for preparing β PVDF by stretching.

Keywords： PVDF β phase γ phase phase transformation deformation