This paper presents the results of a study concerning the dependence of ethylene-propylene rubber's (EPR) conductivity on temperature and electric field. At first, the values of the electrical conductivity are determined experimentally on flat samples of EPR at temperatures of 30, 50 and 70 oC and for dc electrical fields of 5, 10, 15 and 20 kV/mm. Next, the electrical conductivity values are calculated with different empirical equations proposed in the literature, and the obtained results are compared with the experimental ones. It has been found that the difference between the experimental and calculated values is relatively high. As a result, in this paper, a new empirical equation is proposed for calculating the electrical conductivity as a function of temperature and electric field. Finally, it is shown that the differences between the experimental and calculated values for the conductivity using the new equation are much smaller.

Keywords: Ethylene-propylene rubber (EPR), Space charge, Electric field, Temperature, Electrical conductivity, Experimental values, Empirical equation