A Holistic Approach to Evaluate EMI Shielding Characteristics of Carbon Nanotube-based Polymer Composites

Abstract: The work presents a comprehensive methodology to determine the Shielding Effectiveness (SE) of single-walled carbon nanotubes (SWCNTs)/polymer nanocomposites. Here, an algorithm based on Ant Colony Optimization (ACO) was employed to determine the electrical conductivity ({\sigma}) of these nanocomposites as a function of SWCNT concentration. Then, these {\sigma} values were used to compute the SE values as a function of frequency and concentration. Specifically, a pseudo three-dimensional (3D) percolation model was developed to study the effects of random connectivity of SWCNTs to one another on the {\sigma} values of the nanocomposites. Both intrinsic and tunneling resistances were taken into account. The consequences of the presence of both well-exfoliated and aggregated SWCNTs with varying lengths distributed inhomogeneously on {\sigma} and SE values were investigated.