Effect of thermal conductive fillers on the physical and thermal properties of silicone elastomers

The effect of thermally conductive particles on the physical and thermal properties of silicone rubber was studied. Different sized aluminum oxide was blended with addition cured silicone resin at various crosslink densities and filler loading levels. The hardness and thermal impedance of each sample was measured. Statistical analysis of the experimental data showed that hardness was not affected by filler type/size or filler amount; however, the amount of crosslinker was statistically significant with respect to hardness.; Thermal impedence was affected by crosslinker and filler amount in a statistically significant way. As the filler particles are more conductive than the polymer, the greater the amount of filler present, the higher the composite conductivity. Deformation of the material during the test was found to influence the results of the testing.