Effect of small additions of carbon nanotubes on the electrical conductivity of polyurethane elastomer

The effect of small (0.002–0.018 wt %) additions of single-walled carbon nanotubes on the dielectric properties and electrical conductivity of crosslinked polyurethane elastomer is studied in the temperature range of 133–453 K and the 10−3 to 105 Hz range of electric field frequencies. It is shown that the dependence of direct current conductivity σdc on temperature deviates significantly from the Arrhenius dependence and is described by the Vogel-Fulcher-Tamman equation σdc = σdc0exp{−DT0/(T − T0)}, where T0 is the Vogel temperature and D is the strength parameter. A correlation is found between the nonmonotonic dependences of the glass transition temperature (Tg), D parameter, and σdc and the concentration of nanotubes with earlier results for their effects on the physicomechanical characteristics (strength and Young’s modulus) of these systems.