Modelling of electrical percolation and conductivity of carbon nanotube based polymer nanocomposites

Carbon nanotube based polymer nanocomposites due to their excellent electrical, thermal, mechanical and physical characteristics has emerged as a promising material in diverse fields like military, commercial, industrial sectors. The high electrical conductivity of carbon nanotubes is mainly responsible for such diverse applications as in aerospace and electromagnetic interference shielding. This paper deals with the modelling of electrical conductivity and percolation of carbon nanotube based composites for shielding application. It also deals with the effect of carbon nanotube dimensions and interface properties on electrical conductivity of the nanocomposite. It also explains the modification of the existing model so as to avoid the overestimation of electrical conductivity before percolation. The selection of optimum filler volume which helps in optimizing the cost involved in electromagnetic shield preparation is also discussed. Micromechanics modelling is used for estimating the electrical conductivity taking into account the electron hopping and the formation of conductive networks.