Effect of SO2/salt spray environment on properties of conductive rubber

The adaptability of conductive rubber in SO2/salt spray environment was studied by using graphene-filled conductive fluoroether rubber and alloy nickel powder-filled conductive silicone rubber in“SO2/salt spray” test. The macro morphology，Shore A hardness，tensile strength，elongation at break，tear strength and volume resistivity were tested to analyze the influence of the “SO2/salt spray” environment on the properties of conductive rubber. The results show before the test，the Shore A hardness of conductive fluoroether rubber and conductive silicone rubber are equivalent，the tensile strength of conductive fluoroether rubber is higher than that of conductive silicone rubber，and the volume resistivity is lower than that of conductive silicone rubber. After 8 cycles of “SO2/salt spray” test，the macro morphology of conductive fluoroether rubber does not change，Shore A hardness decreases by 3，tensile strength increases by 0.8 MPa（5%），elongation at break decreases by 18%， the volume resistivity increases by 2.1 Ω·cm（65.8%）and there is no change in tear strength；while the conductive silicone rubber has obvious corrosion，with green corrosion products appeared on the surface，Shore A hardness gradually decreases，and the tensile strength decreases by 1.2 MPa（16.4%），the elongation at break decreases by 2%，the volume resistivity decreases by 3.00 Ω·cm（52.4%）and there is no change in tear strength. The analysis of the comprehensive performances obtained by the study shows that the adaptability of conductive fluoroether rubber in “SO2/salt spray” environment is superior to that of conductive silicone rubber.