Carbon nanotube composites for thermal management

Single-wall carbon nanotubes (SWNTs) were used to augment the thermal transport properties of industrial epoxy. Samples loaded with 1 wt % unpurified SWNT material showed a 70% increase in thermal conductivity at 40 K, rising to 125% at room temperature; the enhancement due to 1 wt % loading of vapor grown carbon fibers was three times smaller. Electrical conductivity data showed a percolation threshold between 0.1 and 0.2 wt % SWNT loading. The Vickers hardness rose monotonically with SWNT loading up to a factor of 3.5 at 2 wt %. These results suggest that the thermal and mechanical properties of SWNT-epoxy composites are improved, without the need to chemically functionalize the nanotubes. (C) 2002 American Institute of Physics.