Dielectric properties enhancement of PVC nanodielectrics based on synthesized ZnO nanoparticles

Nanodielectrics based on metal oxide nanoparticles (NPs) exhibit significant improvement in dielectric performances. This study was carried out to examine the dielectric properties of Poly vinyl chloride (PVC) with the introduction of zinc oxide (ZnO) NPs synthesized by simple sol gel method. The microstructure and surface morphology of the synthesized ZnO NPs were characterized by X-ray diffraction (XRD) and field emission scanning microscopy (FE-SEM). The formation of the wurtzite-type ZnO was verified from XRD with average crystallite sizes around 35 nm. PVC/ZnO-NPs nanocomposites were prepared by the solution-cast technique with two different procedures of NPs addition. The dielectric properties of PVC/ZnO nanocomposites were studied by measuring the DC dielectric strength with constant 1 kV/s ramp and the dielectric response as function of frequency from 500 Hz to 1 MHz. A significant enhancement in breakdown strength has been observed with addition of ZnO NPs. The breakdown strength values reached up to 45 % (for PVC/0.14 vol% ZnO) more than obtained for the pristine PVC sample. The effect of dispersibility of NPs due to the used procedures of addition on the DC dielectric strength was studied and confirmed by FE-SEM. The dependency of the real part of permittivity (ε ^′) on filler concentration was observed and confirmed the obtained results from DC dielectric strength.