Octavinyl Polyhedral Oligomeric Silsesquioxane on Tailoring the DC Electrical Characteristics of Polypropylene

This work reports the effect of octavinyl polyhedral oligomeric silsesquioxane (OvPOSS) on tuning the electrical performance of polypropylene (PP). OvPOSS with different content are introduced into PP using the solution method. The microstructural morphology, crystallinity behaviour, breakdown strength, DC conductivity, space charge formation, and trapping level distribution are measured. The results indicate that the OvPOSS nanofiller can be dispersed uniformly with a doping content of 2.0 phr or less. The DC conductivity is decreased, and the breakdown strength of OvPOSS/PP nanocomposites is significantly increased. The space charge accumulation of the OvPOSS/PP nanocomposites is significantly suppressed due to the introduction of deeper traps by the OvPOSS nanofiller. Finally, the experimental results demonstrate that the OvPOSS nanofiller can greatly increase the electrical performance of the base PP and the OvPOSS/PP nanocomposites have much potential for HVDC applications. They further demonstrate that the PP is environmental-friendly due to its thermo-plastic property, which can be recycled after the manufacture.