Space-charge measurement in polymer films by the new alternating thermal wave method

Space-charge prospecting is commonly used as a way of evaluating the electrical qualities and reliability of insulating polymers. However, the various methods for space-charge measurement are not adapted to thin films. The present work is concerned with the development of a new method suitable for thin polymer films intended for the manufacture of capacitors. The principle is the processing of the current response of a film sample submitted to alternating thermal stimulations. A controlled thermoelectric module is used to generate the thermal stimulations. The current response is processed as arising from an equivalent pattern of discrete charged planes, parallel to the film faces. Some results obtained with this model on 100 mum thick polypropylene films submitted to various treatments are given. (C) 2002 Society of Chemical Industry.