A numerical study on electrical conductivity in hybrid composites—Quantitative analysis of morphology variations in percolating networks

Hybrid composites comprising conducting nanowires (NWs) and insulating particulate fillers exhibit varying trends in their electrical conductivity based on the conditions of the constituent fillers. This study presents a quantitative model that comprehensively describes these changes, encompassing both increasing and decreasing trends. The model is formulated as an equation with two parameters quantifying the excluded volume effect and the NW bending effect, which are considered the primary factors determining NW network morphology in the composites. The influence of the parameters on the electrical conductivity of hybrid composites is analyzed with respect to the size and content of the constituent fillers using Monte Carlo-based simulations and statistical regression techniques. Numerical investigations reveal that distinct conductivity patterns under various particulate filler dimensions result from the interplay of these effects. The proposed model, validated through 2-D and 3-D simulations, effectively captures these complex interactions across diverse configurations of the constituent fillers.