Study of $$\upbeta $$ β -phase development in spin-coated PVDF thick films

Abstract

A study was conducted to ascertain the effect of variation in spin speed and baking temperature on $$\upbeta $$ -phase content in the spin-coated poly(vinylidene fluoride) (PVDF) thick films ( $${\sim }4{-}25\,\upmu \hbox {m}$$ ). Development of $$\upbeta $$ -phase is dependent on film stretching and crystallization temperature. Therefore, to study the development of $$\upbeta $$ -phase in films, stretching is achieved by spinning and crystallization temperature is adjusted by means of baking. PVDF films are characterized using Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy. It is observed that crystallization temperature lower than $$60^{\circ }\hbox {C}$$ and increase in spin speed increases the $$\upbeta $$ -phase content in PVDF films. Crystallization temperature above $$60^{\circ }\hbox {C}$$ reduces $$\upbeta $$ -phase content and increases $$\upalpha $$ -phase content. It was also observed that viscosity of the PVDF solution affects the $$\upbeta $$ -phase development in films at a particular spin speed.