Preparation and properties of multilayer graphite/silicon resin thermal conductive materials

With silicon resin as the base matrix materials, filled with multilayer graphite, the thermal conductive multilayer graphite/silicon resin composites were prepared by using the method of rotating-mixer. The effect of filler on the thermal conductivity, coefficient of thermal expansion (CTE) and the thermal stability of the composites were investigated. Results show that the multilayer graphite in silicon resin has good dispersibility. The thermal conductivity of the composites increases with the increasing content of multilayer graphite, and it reaches 2.26 W?(m稫)^-1 when the mass fraction of the filler is 45%, and it begins to decrease when the mass fraction of the filler higher than 45%. CTE decreases as the filler loading increasing. The thermal stability of the silicone resin can be effectively improved through adding multilayer graphite. With the same filler loading, multilayer graphite filled silicone resin possesses higher thermal conductivity compared to SiC and AlN filled silicone resin. It proves that the flake graphite with big radius-thickness ratio can be more likely to form thermal network and improve the thermal contact.