Effect of Annealing and Time of Crystallization on Structural and Optical Properties of PVDF Thin Film Using Acetone as Solvent

Abstract

In this report pure poly(vinylidene fluoride) (PVDF) films were prepared by casting method using acetone solvent. The crystallization of both α and β phase from acetone solvent by varying the time of crystallization has been described. This paper also describes the enhancement of β phase at different annealing condition. β phase dominant thin films were obtained when as cast thin films were annealed at 90 ºC for 5 hours. The PVDF films with dominant α-phase were obtained, when time of crystallization is extend. From (X-ray diffraction) XRD and Fourier Transform Infrared Spectrum (FTIR) it is confirmed that the PVDF thin films, cast from acetone solution and annealed at 90 ºC for 5 hours, have maximum percentage of β-phase. Presence of the crystalline α and β phases in each sample was confirmed by X-ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). We found that of PVDF when crystallized from its acetone solutions led to the formation of β phase. UV-visible optical absorption analysis revealed a change in the optical gap and shift in absorption edge with annealing temperature.