Effect of interface on space charge in polyethylene

Reports the results of an investigation into the space charge formation and decay at the interface between two layers of polyethylene. The influence of interface between electrode and polymer or polymer and polymer on the space charge formation and distribution has been studied. Planar samples were subjected to high dc electric stress for extended periods of time and space charge measurements taken using the pulsed electroacoustic (PEA) technique. It has been found that (i) types of interface between electrode and polymer play a significant role in determining charge distribution in the insulation, (ii) the interface between polymer and polymer acts as a potential barrier to electrons while allowing holes through easily.