Post-annealing effects of electroless Ni-B-plated MWCNTs on thermal conductivity of epoxy-based composites

This study investigated the heat-treatment-induced changes on the surfaces of electroless Ni-B-plated MWCNTs, in addition to the MWCNTs' resultant effects on the thermal conductivity of epoxy composites. The surfaces of the heat-treated MWCNTs were analyzed by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The ASTM D5470 standard test was used to record the composites' thermal conductivity. The surface crystallinity of the MWCNTs was shown to improve with increasing heat-treatment temperatures, and their incorporation increased the thermal conductivity of the epoxy composite. In particular the Ni-B 500/EP sample showed more than 110% enhancement of thermal conductivity compared to the Ni-B 0/EP sample. These results were attributed to the interfacial adhesion between the CNTs and EP matrix in the composites.