Oxidized Graphite Nanoplatelets as an Improved Filler for Thermally Conducting Epoxy-Matrix Composites

Abstract

We report a 40% improvement of the thermal conductivity of graphite nanoplatelets–epoxy composites by chemical functionalization of graphite nanoplatelets utilizing nitric acid treatment, which also serves to enhance the spreadability of the material. FTIR and Raman spectroscopy confirmed the presence of a variety of oxygen functional groups at the edges and basal plane of the functionalized graphite nanoplatelets, which contributed to improved interaction with the polymer matrix. A comparative statistical analysis of the particle size distributions in pristine and functionalized graphite nanoplatelets based on scanning electron microscopy showed an increasing degree of exfoliation of the functionalized material. We compare the performance of the functionalized graphite nanoplatelets and carbon nanotubes as fillers in the polymer matrix and discuss the prospects for utilization of graphite nanoplatelets-based thermal interface materials in electronic packaging.