Enhanced dielectric properties of graphene and conjugated terpolymer-blended polyvinylidene difluoride

In this study, electrically conductive composites of ethylenedioxythiophene-based terpolymer (PETCH), polyvinylidene difluoride (PVDF) and graphene nanosheets (GNS) have been prepared by compression molding and characterized. A new conjugated PETCH polymer was synthesized and its chemical structure has been confirmed by Fourier transform infrared and 1H-NMR spectroscopy. The varying weight percentages of (1, 3 and 5%) GNS and 10 wt% PETCH dispersed PVDF nanocomposites were prepared and characterized using X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDX) analysis. The thermal studies indicated that the decomposition occurred at a temperature around 220°C, and 480°C corresponds to the PETCH and PVDF/PETCH/GNS (1, 3 and 5%), respectively. The EDX spectrum of neat PETCH polymer and their composites of PVDF/PETCH/GNS (1, 3 and 5%) result clearly shows the presence of all elements such as, C, O, S, F and Cl with an atomic weight percentage. The PVDF/PETCH/5% GNS has a dielectric constant value of 3.9 at 1 MHz and the conductivity of this polymer composites value is found to be 5.8 × 10–6 S cm–1 at 1 MHz, respectively. Results obtained from the dielectric studies indicated that the GNS and terpolymer-dispersed PVDF composites exhibit good interfacial adhesion as evidenced from conductive behaviours.