Thermal and AC breakdown properties of polypropylene/ethylene-butene elastomer blends

Recently, many types of elastomers have been explored in polypropylene (PP) blend systems as they can modify the mechanical and electrical properties of PP. However, the addition of elastomer to PP may negatively affect the electrical properties of the final blend and hence become the main challenge in PP modification. In this paper, the electrical properties and thermal behaviour of polypropylene/ethylene-butene elastomer (PP/EBE) blends were evaluated. Six samples were prepared by a melt-mixing technique, including pure PP and PP/EBE blends at different elastomer contents. The thermal behaviour of PP blends was characterized by using differential scanning calorimetry (DSC). The obtained results indicated that the addition of 20 wt.% of EBE led to the highest AC breakdown strength. EBE content beyond 30 wt.% appeared to reduce breakdown strength significantly. Meanwhile, the inclusion of EBE in PP blend did not remarkably affect the thermal properties. The crystallinity reduced as the EBE content increased.