Thermal conductivity of in situ epoxy composites filled with ZrB2 particles

Abstract The incorporation of highly thermally conductive ceramic materials in polymers could improve effectively the thermal conductivity of polymer matrix. In this work, Zirconium diboride (ZrB 2 ) particles with high thermal conductivity were introduced into an epoxy polymer matrix by in situ synthesis method for the improvement of thermal conductivity of epoxy matrix. The thermal conduction of epoxy composites was investigated by laser flash method and numerical analysis. The dispersive status of the fillers was characterized by transmission electron microscopy (TEM). The results showed that the thermal conductivities of epoxy resin were increased significantly due to the addition of ZrB 2 particles. The thermal conductivity of epoxy composites increases with the increase of ZrB 2 particles loading ranging from 0 wt% to 16 wt%. The enhancement of thermal conductivity exhibited a little change when the particles content exceeded 12 wt%. The influence of the temperature on the improvement of thermal conductivity was inconspicuous. The thermal conductivity of ZrB 2 /epoxy composites increased slightly with the increase of temperatures in the range of 25–100 °C. The distribution of ZrB 2 particles in the matrix affected the thermal conductivities of epoxy composites greatly. In comparison, the composites with 12 wt% ZrB 2 particles loading presented better dispersion of the particles in the epoxy matrix than those of the other composites. The thermal conductivity values of the composites at 12 wt% loading obtained by finite-element analysis (FEA) were in good agreement with the experimental value.