Electrical properties of surfaces of unirradiated and irradiated polymers in humid environments

The surface charge decay of corona-charged polyether ether ketone (PEEK) and polypropylene (PP) for different charging potentials in humid environment is studied. The PEEK charge decay consists of a fast decay followed by a slow decay. The fast decay process may have originated from a field-induced dielectric polarization and the slow process from a thermal hopping process. The PP charge decay is insignificant over an extended period of time. The adsorption of water in humid environment is more for PEEK with gamma irradiation and less for PP.