The ethylene-propylene-diene monomer（EPDM）

polyolefin elastomer（POE） and ethylene-vinyl acetate copolymer（EVA）

with the weight ratio of elastomer is 40%

were respectively added into polypropylene（PP） to improve its toughness

and the space charge behaviors of different polypropylene composites were measured with the pulsed electro-acoustic（PEA） method so as to compare the potential of these composites for HVDC cable application. It is found that the PP composites show better toughness and lower tensile strength than pure PP. As charges can easily accumulate in the interfaces between PP and elastomer

the amount of space charge and the electric field enhancement in PP composites are higher than those in PP. The addition of elastomer improves volume resistivity of PP. A large amount of space charge accumulates in PP/EPDM composite and the toughness of PP/EVA composite is unsatisfactory

while the PP/POE composite shows excellent mechanical and electrical properties.