Effects of electrodes on space charge in low-density polyethylene

The effects of electrode on space charge in low-density polyethylene (LDPE) were measured with the pulsed electro-acoustic (PEA) method. The thickness of a specimen was about 100 /spl mu/m. The electrode materials used were aluminum and semiconductive (SC) polymer. Charge carriers were mainly injected from the SC electrode in a specimen of A1/LDPE/SC and they moved to the counter A1 electrode. The evaporated A1 electrode injected much less carriers than the A1 plate electrode mechanically contacted. We also used a fluorinated ethylene propylene copolymer (FEP) film as a blocking layer.