Thermal properties and percolation in carbon nanotube-polymer composites

Thermal properties of single walled carbon nanotube (SWNT)/polymethylmetacrylate composite thick films have been investigated at room temperature. The introduction of ∼7% SWNT into the polymer matrix enhances the thermal conductivity of the composite by 55% while the electrical conductivity increases by several orders of magnitude. Despite this difference, we show that the (moderate) enhancement of the thermal conductivity is quantified by the percolation of the SWNT network. A thermal conductivity of the SWNT network of ∼55W∕mK is estimated.