Preparation And Experimental Study On The Thermal Interface Materials Of Silicone Rubber

To fulfill the increasing requirements of the thermal conductivity of TIM (Thermal Interface Materials) in the field of micro-electronics, the composite materials of silicone rubber of high thermal conductivity was prepared by mechanical mixing with alumina, aluminum nitride and nanometer flake carbon powder as thermal conductive fillers and methyl vinyl silicone rubber as matrix. And some experiments were performed to study the modification technology of coupling agent to the fillers and its effect on the thermal conductivity of the composite materials. Also, the effects of the type, content, particle size and ratio of thermal conductive fillers on the thermal conductivity, mechanical properties and thermal stability of the composite materials were studied. The research results showed that:(1)With the fillers of the composite materials processed with coupling agent, all the thermal conductivities were increased. The thermal conductivities of alumina, aluminum nitride and nanometer flake carbon powder composite materials increased while the volume fraction of the fillers increased. However, when the filling fraction at a low level, the thermal conductivity of silicone rubber was changed slowly, and when the filling fraction reached a certain high level, the thermal conductivity would increased faster.(2) With our different particle sizes (75μm,35μm,3μm, and100nm) of alumina used together for preparation of composite materials, when their content ratio was1:5:1:1, the highest thermal conductivity would be2.90W/(m-K); With alumina and aluminum nitride used together for preparation of composite materials, when the content ratio of AlN (aluminum nitride) was0.6, the thermal conductivity reached the highest value of4.34W/(m-K); With AlN and nanometer flake carbon powder used together for preparation of composite materials, when the content ratio of AlN was0.8, the thermal conductivity reached the highest value of3.98W/(m-K).(3)The tensile strength of the composite material was positively correlated with the volume fraction of the fillers, and elongation at break and tear strength was negatively correlated with the volume fraction of the fillers. And the thermal stability of the composite materials would be better when the volume fraction of the fillers was higher...