Preparation and ferroelectric properties of poly (vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) filled with graphene-nanoplatelets film composites

Abstract

The poly(vinylidene fluoride-co-hexafluoropropylene), PVDF-HFP composite films with addition graphene-nanoplatelets (GPN) was prepared by using the tape casting solution method. The obtained composite films were stretched with help from thermal stretching machine at 80 °C with 5 mm/min rate. Dielectric constant and hysteresis loop (PE-loop) between the stretching and non-stretching films at different fillers percentage were compared in this study. Dielectric constant was investigated by the LCR meter. The PE-loop was measured by the ferroelectric polarization loop test system. The experimental results showed that the dielectric constant of all samples increases with increasing fillers content, regardless of frequency. The dielectric constant of stretching composite films was higher than non-stretching composite films. In addition, the PE-loop shapes of the stretching films have slimmer than the non-stretching films regardless of filler content. However, the PE-loop produced the shape to be bigger loop with increasing filler content. The energy efficiency of obtained PVDF-HFP composite films will be discussed on their dielectric constant, dielectric loss, AC conductivity, and polarization performances for electric–capacitor materials applications.