Abstract: Effects of three kinds of compatibilizers, maleic anhydride grafted high-density polyethylene (PE-g-MAH), ethylene vinyl acetate (EVA) and styrene-butadiene-styrene block copolymer (SBS), on electrical properties of high-density polyethylene (PE-HD) / polycarbonate (PC) /carbon black (CB) composites were studied. It showed that the addition of compatibilizers to PE-HD/PC/CB composites promoted the positive temperature coefficient （PTC）, and the modification effect of SBS was the best among the three compatibilizers. When the content of SBS was 4 wt %, the PTC intensity of the composite increased by 14.3 % based on neat PE-HD/PC/CB composite. The promotion of PTC intensity by PE-g-MAH was less than that of SBS. EVA had the advantage to inhibit the negative temperature coefficient （NTC） phenomenon, the NTC intensity of the composites decreased from 0.3 to 0.08.

Key words: high density polyethylene, polycarbonate, carbon black, compatibilizer, positive temperature coefficient, negative temperature coefficient