The correlativity of positive temperature coefficient effects in conductive silicone rubber

A thorough study on the positive temperature coefficient (PTC) effects of conductive silicone rubber was made. Various conductive silicone rubbers with apparent differences in PTC anomalies (defined as the ratio of peak resistivity to room temperature resistivity) were chosen. The correlation between the size of the PTC anomaly and both the thermal expansion coefficient of conductive silicone rubber and the interaction between silicone rubber and carbon black (CB) were found. The effects of cross-linking on the temperature effect of resistivity of conductive silicone rubber were also studied. The results testify the important role of the interaction between silicone rubber and CBs in the temperature effect of resistivity of conductive silicone rubber. (c) 2005 Society of Chemical Industry.