Simulation of tunneling distance and electrical conductivity for polymer carbon nanotubes nanocomposites by interphase thickness and network density

This article develops simple equations for tunneling distance between adjacent nanoparticles (d) and electrical conductivity of polymer/carbon nanotubes (CNT) nanocomposites (PCNT). The developed model considers the significances of CNT dimensions and waviness as well as interphase region surrounding CNT on the conductivity of nanocomposites. Moreover, d is defined by the sizes of CNT, interphase thickness and network density. The roles of all parameters for nanoparticles, interphase, percolation threshold and conductive network in the nanocomposite conductivity and tunneling distance are determined. Among the studied parameters, the fraction of percolated CNT of 0.6 and d = 1 nm provide the highest conductivity of PCNT, while d > 2.5 nm cause an insulated nanocomposite. In addition, the high concentration of thin CNT, a thick interphase, poor waviness, low percolation threshold, and the small fraction of percolated CNT produce an optimized level for d.