Preparation and Properties of BN/Si3N4/Epoxy Composites

The effect of a hybrid filler on the thermal conductivity of an epoxy composite is described. The hybrid filler, containing boron nitride (BN) particles and silicon nitride (Si3N4) whiskers with different wt% ratios (20:0, 18:2, 15:5, 10:10, 5:15, 2:18 and 0:20), was loaded into the epoxy resin. The thermal conductivities of the doped composites were higher than that of the pure EP (0.4287 W center dot m(-1)center dot K-1); with addition of BN and Si3N4 fillers the 10%BN/10%Si3N4/EP composites exhibited the highest thermal conductivity (1.1486 W center dot m(-1)center dot K-1), which was 185% and 214% that of the 20%BN/EP composite (0.6200 W center dot m(-1)center dot K-1) and the 20%Si3N4/EP (0.5374 W center dot m(-1)center dot K-1), respectively. The impact strength of the composite material 10%BN/10%Si3N4/EP also was the maximum (3.48 KJ/m(2)). Thus, the 10%BN/10%Si3N4/EP composites not only exhibited excellent thermal conductivity, but also slight improvements in thermal stability and impact strength. Suggesting it would be useful for thermal sensor interconnections of electronic circuits.