Effect of single-walled carbon nanotube purity on the thermal conductivity of carbon nanotube-based composites

Raw [as-prepared (AP)] and purified single-walled carbon nanotubes (SWNTs) were utilized for the preparation of SWNT-epoxy composites. Purified functionalized SWNTs provide a significantly greater enhancement of the thermal conductivity, whereas AP-SWNTs allow the best electrical properties because of their ability to form efficient percolating network. A series of SWNT samples of varying purity but identical chemical functionality was prepared to delineate the effect of SWNT purity on the thermal conductivity of SWNT-epoxy composites. The authors found that purified SWNTs provide approximately five times greater enhancement of the thermal conductivity than the impure SWNT fraction demonstrating the significance of SWNT quality for thermal management.