Transport properties of PMMA-Carbon Nanotubes composites

We report transport measurements on PMMA-singlewalled carbon nanotubes composites films. The films are characterized by Raman spectroscopy, optical absorption and electron microscopy. At room temperature, classical percolation theory applies. It shows that the composites resistivity is indeed controlled by the nanotubes. Decreasing the temperature shows a unusual behavior which suggests that a distribution of intertube/interbundle barriers of some 10 of Kelvin is superposed to the topological percolation problem.