ELECTRICAL-PROPERTIES OF CHEMICALLY-MODIFIED POLYETHYLENES

This report describes electrical properties such as space charge distr ibution, water treeing characteristics and ac breakdown strength in PE (polyethylene) modified by grafting and blending techniques. A contro l PE shows heterocharge. In AA (acrylic acid)-grafted PE (LDPE-g-AA), the heterocharge observed in PE decreases at low AA contents and homoc harge is observed at high AA contents. In NEA (n-butyl acrylate)-graft ed PE (LDPE-g-NBA), on the other hand, this heterocharge gets larger a t all graft ratios to 0.12%. However, these components decrease the wa ter tree length measured under specific conditions and increase ac bre akdown strength. Details of the results are described and their origin s are discussed. The results obtained with the LDPE-g-NBA are compared with those of PE/ethylene NEA copolymer blends.