DC Breakdown Performance of Silica and Zirconia Based Polyethylene Nanocomposites

Polymer nanocomposites have become one of the main research studies in exploring the potential use of advanced insulating materials in high voltage insulation. From previous research on nanocomposites, promising results of polyethylene nanocomposites have been reported, and the interface between the base polymer and the nanofiller has been attributed as one of the factors affecting the dielectric breakdown performance. This paper reports on an investigation into the DC breakdown performance of unfilled and polyethylene nanocomposites containing silicone dioxide (SiO2) and zirconium oxide (ZrO2) nanofillers at 1 wt%, 4 wt%, and 8wt% loading levels. The chemical structures of the materials were characterized using Fourier transform infrared (FTIR) spectroscopy and the morphology of the materials were determined using scanning electron microscopy (SEM). The breakdown results showed that, introducing small amounts of nanofillers could have a major impact on the DC breakdown strength. Nevertheless, samples containing ZrO2 had higher breakdown strength than those containing SiO2. The mechanisms governing these changes are discussed.