Effects of drawing on space charge behavior of LDPE film

In this paper, the effects of drawing on space charge behavior of LDPE have been investigated by the pulsed electro-acoustic method at 20/spl deg/C with the electrode system of aluminium/sample/semiconductive layer. Two kinds of LDPE films were used, one was an original LDPE film without drawing and the other was LDPE film with drawing process. The LDPE film after drawing had more space charge than the LDPE film without drawing under a DC field of 50 MVm/sup -1/. The decay of positive space charge during short-circuiting has two time constants. The drawn film has longer time constants than the original film. This result suggests the modification of traps by drawing.