Numerical investigation on the influence factors of the electrical properties of carbon nanotubes-filled composites

In order to predict the electrical properties of carbon nanotubes-filled composites, a three-dimensional (3D)numerical model is proposed. A random distribution of impenetrable conducting cylinders inside a cubic insulating matrix models the morphology of the considered material. The variation of the macroscopic electrical performances of the simulated structures is estimated through a suitable 3D resistance and capacitance network associated with the different percolating paths. The introduction in the model of the capacitive effects exhibited by the material, usually not considered in other simulation approaches, allows also a significant analysis in the frequency domain. The electron tunneling effect between conducting structures, determinant in the polymer nanocomposites, is also accurately taken into account to study the composite properties. The obtained results are in good agreement with theoretical predictions and experimental data suggesting that the proposed model can properly estimate different effects upon the electrical properties providing useful hints for the optimization of nanocomposites.