Effect of Thixotropic Agent on the Properties of Conductive Silicone Rubber Gasket for EMI Shielding

In this study, a thixotropic agent was applied to improve the aspect ratio of the silicone rubber gasket and the resulting obtained through modification showed an increase in aspect ratio from 0.26 to 0.91 with the relative to the gasket without thixotropic agent. Compared with the silicone rubber without thixotropic agent, the mechanical properties of the silicone rubber with thixotropic agent were discussed and the results revealed that the shift was very small. In addition, using Ag-coated Cu dendritic powder as conductive fillers, conductive silicone rubber with the resistivity (0.004Ω·cm) was prepared comparable to the relative commercial products can be used for electro-magnetic interference (EMI). The reliability of the conductive composites under aging at 85°C and 85% room humidity (RH) in a temperature/humidity chamber for 48 h was also discussed and the results showed that the shift of the volume resistivity was almost negligible which can meet the actual needs completely.