Effect of Plasma Polymer Treatment on Aging of Polyethylene Films

Aging degradation of solid insulation is traditionally studied using various failure acceleration mechanisms alone or in combination. For example, multiple stress conditions, including electrical signals, elevated temperature, and/or a corrosive (saline) environment are often applied to molded insulation blocks that have been cut, scratched, or implanted with sharp metallic electrodes to provide a site for the onset of failure. The test configuration used in this study involves thin (50 ?m) commercially available polyethylene sheets lacking artificially induced defects. Periodic measurements are made on films while they are under soak in a saline solution with a sinusoidal voltage applied. Capacitance and dissipation results are presented which are indicative of the degradation induced by the stress conditions on untreated polymer films and on polymer films which have been coated with extremely thin (\u3c100 nm) plasma polymerized films of two monomer