Effects of SiO2 and ZrO2 on the AC breakdown performance of polyethylene

In electrical insulation, polymer nanocomposites become one of the main research areas for exploring the potential of insulating materials in terms of dielectric strength enhancement. This is due to many promising results of nanocomposites reported by the dielectrics community. For this, the interfaces between the filler and base polymer is one of the major factors for improving the filler/ polymer interaction within the nanocomposites. This paper reports on an investigation into the AC breakdown performance of unfilled and nanofilled polyethylene. With different nanofillers (silicone dioxide (SiO 2 ) and zirconium oxide (ZrO 2 )) and different loading levels (1 wt%, 4 wt%, 8 wt%). The thermal behavior of the materials was characterized using differential scanning calorimetry (DSC) and the melting traces for the materials were determined. The breakdown results showed that a low nanofiller loading level (1 wt%) did not significantly affect the breakdown strength compared to the unfilled sample. When comparing samples containing SiO 2 and ZrO 2 nanofillers, it appeared that those with ZrO 2 filler had slightly higher breakdown strength compared to those containing SiO 2 nanofiller. The significance of the results is discussed.