Electrical properties of single wall carbon nanotube reinforced polyimide composites

Electrical properties of single wall carbon nanotube (SWNT) reinforced polyimide composites were investigated as a function of SWNT concentration. AC and DC conductivities were measured, and the frequency behavior of the specific admittance was investigated. The experimental conductivity was found to obey a percolation-like power law with a relatively low percolation threshold. The current-voltage measurement results exhibited a non-ohmic behavior, indicating a quantum tunneling conduction mechanism. Analytical modeling and numerical simulation using high aspect ratio, rigid, spherocylinders as models for the SWNT were carried out to aid in understanding these results. The predictions were in good agreement with the experimental results.