Charge motion on moist polymer surfaces

Solid polymeric insulation materials such as low density polyethylene (LDPE) and cross linked polyethylene (XLPE) are employed in high voltage situations and in sensitive current measuring apparatus because of their very high resistivities. However, a consequence of these insulation properties is that charges, once deposited onto a surface, may remain there for a very long time and give rise to spurious surface potentials. Indeed the decay of surface charge may be so slow that it is often impossible to determine whether conduction occured through the bulk or along the surface.