Effect of Titanium oxide Nanofiller on the Electrical Properties of Polypropylene Nanocomposites for HVDC Insulation

Polypropylene (PP) is considered as a potential insulation material to replace conventional cross-linked polyethylene (XLPE) in high voltage direct current (HVDC) as it possesses excellent thermal and electrical properties. This paper aims to investigate the effect of titanium dioxide (TiO2) nanofillers on the DC breakdown strength of PP nanocomposites. TiO2 was synthesized in laboratory using Sol-Gel procedure. PP nanocomposites were prepared by incorporating 0.5 wt%, 1 wt% and 3 wt% TiO2 using melt blending method. The crystallinity and morphology of the synthesized nanofillers are investigated using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Differential scanning Calorimetry (DSC) was carried out for investigating the thermal and crystallization temperature of PP nanocomposites. The dielectric breakdown tests revealed that PP containing TiO2 exhibited lower breakdown strength compared to neat PP. Possible mechanisms governing these changes are discussed.