Effect of Carbon Nanotube Aspect Ratio on the Thermal and Electrical Properties of Epoxy Nanocomposites

The novel properties of carbon nanotubes have generated much interest in polymer nanocomposites. The thermal and electrical properties of multi-walled carbon nanotube-epoxy composites were investigated both experimentally and theoretically. Experiments were performed to evaluate the effect of the aspect ratio of carbon nanotubes. Comparisons were made between the results obtained for the nanocomposite materials containing carbon nanotubes with a high (800) and a low (80) aspect ratios. Design recommendations were made, and potential applications were also discussed. It was shown that the aspect ratio plays an important in determining the physical properties of the epoxy nanocomposite. The electrical conductivity of the nanocomposite is highly dependent on the aspect ratio of carbon nanotubes. In contrast, the aspect ratio plays a considerable role in the thermal conductivity of the nanocomposite. Carbon nanotubes have clearly demonstrated their capability as thermally and electrically conductive fillers in epoxy nanocomposites. In contrast to the orders of magnitude enhancement in electrical conductivity with a very low loading of carbon nanotubes, the thermal conductivity of the nanocomposite has shown only moderate improvement. The improvement in physical properties of the nanocomposite can be interpreted in terms of carbon nanotube networks.