Spontaneous current of polyethersulfone investigated through the measurement of space charge distribution by the pulsed electroacoustic method and thermally stimulated current

Abstract

The importance of engineering plastics such as polyethersulfone (PES) has become recognized in the field of machine and cable insulation. PES is an amorphous thermoplastic polymer with a high glass transition temperature of 225°C. In previous reports, the mechanism of electrical conduction in PES was studied through dc conduction current, thermal pulse current, and thermally stimulated current. A current flowing in the sample has been observed without the application of electrical stress. In this work, the origin of this spontaneous current is studied based on the experimental results on thermally stimulated current and space charge distribution. The sample used is PES (TAI PA-1000) in the form of a film with thickness of 125μm. The space charge distribution is measured by the pulsed electroacoustic method.