Surface charge relaxation in silicone rubber and EPDM

The paper focuses on analyzing relaxation of charges deposited on surfaces of silicone rubber and ethylene propylene diane rubber samples by positive impulse corona in air. The developed computer model accounted for gas neutralization of the surface charges, their injection and transport in the bulk of solid materials. The simulations showed that surface charge decay takes place mostly due to neutralization by atmospheric ions while charge injection and transport in the solids led to formation of homo charge layers at interfaces. Characteristics of surface charge decay were found to be similar for both materials in the beginning of the relaxation process and slightly different at long times. The model results are in agreement with surface potential decay measurements.