Abstract:
In order to investigate the properties of semi-conductive screen material for PP cable, polypropylene/ethylene octene copolymer elastomer (PP/POE) was used as the base material, and carbon black was added to the matrix resin as the conductive filler. The semi-conductive shielding materials with different POE ratios were prepared by a torque rheometer. The distribution of carbon black in the material was observed by scanning electron microscope (SEM), and the crystallization behavior of the material was characterized by differential scanning calorimetry (DSC). Moreover, the thermodynamics of the sample was analyzed, and the volume resistivity at different temperatures was measured by a four-electrode system. The results showed that the addition of POE changed the distribution of carbon black, which was mainly distributed in POE. With the increase of POE content, the distribution area of carbon black network becomes larger, but the concentration of carbon black is lower. The PTC effect of volume resistivity is enhanced. In general, PP and POE with the ratio of 60:40 and 50:50 possess ideal mechanical and electrical properties.