Effect of degradation on electrical charging of polymer

Static electrification of polypropylene polybutene-1 copolymer was investigated by means of a corona discharge. The charging characteristic of the photodegraded film was compared with that of the original film. The initial surface potential of the degraded film was smaller and decayed faster than that of the original film. The chemical change of the films was measured by means of Fourier transform infrared absorption spectrum analysis. It was confirmed that the carbonyl group and the hydro-peroxide had increased due to the irradiation of ultraviolet rays applied to the specimens. The activation energy of the electrical conduction was measured by the thermally stimulated current method. It was surmised that the activation energy of the electrical conduction of the degraded film became small because the physical trap in the crystalline part had increased due to the cutting of the molecular chain. The decrease of the activation energy affected the charging characteristic of the polymer