Frequency dependence of effective permittivity of carbon nanotube composites

Dependence of the permittivity of single-walled and multiwalled carbon nanotube composites on frequency and concentration was investigated experimentally using the coaxial air-line method over 0.1–10 GHz. The results are in good agreement with that obtained using the impedance method. It is found that scaling law based on the percolation theory provides a good description of the frequency dependence of measured permittivity in carbon nanotube composites. Parameters of the scaling law and deviations from the percolation theory are also discussed.