Conductivity Characteristics of CB/LDPE Composites at Different Temperatures

As a new kind of nanocomposite material, CB/LDPE has attracted wide attention in recent years. In this paper, CB/LDPE composites with a small doping content (0.03wt%) were fabricated by using the melt blending method. Conductivity characteristics of LDPE and CB/LDPE films were measured at different temperatures and different electric field. Space charge injection threshold and activation energy at different temperatures were calculated for both films. The experimental results show that, compared with LDPE material, the CB/LDPE material increases the space charge injection threshold and weakens the dependence of the conductivity on temperature. The analysis indicates that the improvement of conductivity characteristics of CB/LDPE is related to the formation of the homo-polarity charge layer on the surface of the sample. This is beneficial to the development and utilization of CB/LDPE materials in the new materials of HVDC cable.