Thermal and electrical properties of carbon nanotube-based epoxy composite materials

Abstract

The novel properties of carbon nanotubes have generated much interest in nanostructured polymer composite materials. The effect of multi-walled carbon nanotube aspect ratio on the thermal and electrical properties of nanostructured epoxy composite materials was investigated both experimentally and theoretically. Both thermal and electrical conductivity measurements were performed, and comparisons were made between the results obtained for the nanostructured composite materials containing carbon nanotubes with different aspect ratios. Potential applications of these nanostructured composite materials were discussed, and design recommendations were also made. The numerical and experimental results indicated that the aspect ratio plays an important in determining the physical properties of the nanostructured epoxy composite materials. The electrical conductivity of the nanostructured composite materials 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 composite materials. Multi-walled carbon nanotubes are capable of improving both thermal and electrical performance of the polymer matrix. In contrast to the orders of magnitude enhancement in electrical conductivity with a very low loading of carbon nanotubes, the thermal conductivity of the composite materials has shown only moderate improvement. The improvement in physical properties of the composite materials can be interpreted in terms of carbon nanotube networks.