The mechanism of electrical conduction in polyethylene/carbon black composite

The mechanism of electrical conduction in the polyethylene (PE)/carbon black (CB) composite is investigated in this paper. It has been found experimentally that there are three distinct regions in the J-E curve of the PE/CB composite. On the basis of energy band of the conductance grain--insulation dielectric--conductance grain system, the electrical conduction equation can be derived correspondingly according to the change in barrier potential under different electric fields. It shows that JµE in the low field strength, Log J/EµE in middle-field strength and Log J/Eµ-1/E in the high field strength. The equations fit well with the results obtained from experiments. The evidence suggests that the mechanism of conduction processes in the PE/CB composite can be attributed to the electrons tunnelling through the intergranular gaps among the CB particles