Dielectric Behavior and Transport Properties of Electrospun Polyvinylidene Fluoride Nanofiber Membrane

Poly (vinylidene fluoride) (PVDF) is a chemical resistance polymer with high ferroelectric, piezoelectric and pyroelectric properties. PVDF has been chosen due to its unique properties compared with others in the polymers family and is used in a variety of sensors and transducers. A PVDF nanofiber membrane with relatively uniform morphology was prepared by an electrospinning technique. The surface morphology of the electrospun PVDF nanofibers was observed by scanning electron microscopy (SEM). The microstructure of electrospun PVDF nanofibers was characterized by Fourier Transform Infrared spectroscopy (FTIR) in the range 400 to 4000 cm-1. The functional groups were identified in the membrane. Infrared vibrational spectroscopy (FTIR + Raman) curves revealed a ferroelectric β-phase in the un-annealed membrane intrinsically. It showed that the electrospinning technique induce crystalline and polar β-phase by applying an electric field to the PVDF polymer solution during high solution jet stretching. The membrane (7 mm x5 mm) with full-face copper electrodes was produced to form a capacitor for testing.