ABSTRACT
When plasma polymers of hydrophilic monomers were deposited or the surface of LDPE grafted with hydrophilic poly(acrylic acid), the dielectric breakdown occurred in a very short time. These observations indicate that hydrophilic sites act as the gate for salt intrusion. Since the bulk properties of LDPE are believed to be unchanged with these surface modifications, the quick failure can be interpreted as the consequence of an interfacial phenomenon. The population of the potential salt intrusion sites is a very important factor that ultimately determines the breakdown of the insulation occurring in the presence of salt and electrical stress.
