367 / 2019-03-12 08:55:43

Effect of Fullerene Nanoparticle on Tuning Trap Level Distribution of Fullerene/Polyethylene Nanocomposites

HVDC,cable insulation；,fullenren,trap level,polyethylene

PE nanocomposites treated by silane coupling agent KH550 with filler contents of 0, 0.005 and 0.01 wt% were prepared. In order to verify the effect of KH550, the untreated C60/LDPE nanocomposites with filler contents of 0.005 and 0.01 wt% were also prepared as reference. The trap distribution of C60/LDPE nanocomposites with different contents of C60 was studied by isothermal surface potential decay (ISPD) experiments. The results show that C60 can tune the trap level distribution of C60/LDPE nanocomposites. With the content of C60 increasing from 0 to 0.01 wt%, the trap level of C60/LDPE nanocomposites increases first and then decreases, when the content of C60 is 0.005 wt% and treated by KH550, the best modification effect is obtained. In addition, KH550 treated C60/LDPE nanocomposites have higher trap levels and lower carrier mobility than untreated C60/LDPE nanocomposites when C60 content is 0.005 wt% and 0.01 wt% respectively, indicating that well dispersed C60 introduces more deep traps for LDPE. With the temperature increasing from 25 to 80 ˚C, the charges trapping in the deep trap sites are more likely to detrap, resulting in the increase of apparent deep trap levels. It is deduced that large quantities of deep traps distributed in the C60/LDPE interfacial regions play an important role in the modification of deep trap levels and reduction of carrier mobility.