INTERFACIAL CHARGE IN POLYETHYLENE ETHYLENE VINYLACETATE LAMINATES/

Space charge formation in polyethylene (PE)/ethylene vinylacetate copo lymer (EVA) laminates has been investigated using a pulsed electroacou stic method. The PE shows heterocharge while the EVA shows a broad dis tribution of positive charge over the sample. The positive charge in E VA decreases with the increase of vinylacetate (VA) content in EVA. In terfacial charge is found in all laminates and remains unchanged by he at treatment at 100 degrees C to 1h and by coating chemicals such as s ilicone oil and trimethylolpropane trimethacrylate at the interfaces. This interfacial charge distorts the electric field distribution in th e direction of increasing the electric field in the PE layers. The cha rge distribution in PE/EVA blends has been measured and is explained v ia the results obtained with the laminates.