Fabrication and characterization of thermally conducting laminate using spherical aluminum nitride powders and synthesized twin mesogenic epoxy oligomer

Thermally conducting insulation laminates with high peel strength as well as high thermal conductivity were fabricated by the addition of sintered spherical A1N powders as fillers into twin mesogenic epoxy matrix. A twin mesogenic epoxy oligomer based on biphenyl structure was synthesized. Bimodal or trimodal fillers were added to the synthesized epoxy resin with a curing agent and formed to an insulation laminate, and the thermal conductivity of the cured laminate was measured. Aluminum nitride powders having average size 50 and 10um were used as the bimodal fillers. In particular, 50um A1N powders are sintered spherical particles with narrow size distribution. In addition, 5um BN powders were used the third fillers. The thermal conductivity of the cured thermoset without fillers was over 0.236 W/m-K and that of the thermally conducting laminate reached about 12.55 W/m-K at 75vol% filler loading. Cu peel strength of about 16 N/cm was obtained by 90° peel method. The 20vol% BN-replaced composite showed the higher thermal conductivity of 15 W/m-K.