Percolation of particles on recursive lattices: (III) percolation of polydisperse particles in the presence of a polymer matrix

TL;DR

This paper investigates how particle size, shape, and polymer matrix properties influence percolation thresholds using an exact recursive lattice model, aligning well with experimental observations.

Contribution

It introduces a lattice model that accurately predicts percolation behavior of polydisperse particles in a polymer matrix, considering various physical factors.

Findings

Increasing particle size disparity lowers percolation threshold.

Higher aspect ratio particles also decrease the percolation threshold.

Model results agree with experimental data.

Abstract

We use a recently developed lattice model to study the percolation of particles of different sizes and shapes in the presence of a polymer matrix. The polymer is modeled as an infinitely long semiflexible chain. We study the effects of the stiffness of the polymer, the size disparity of the filler particles, their aspect ratio and the interactions between fillers and polymer on the percolation properties of the system. The lattice model is solved exactly on a recursive Husimi lattice. The solution represent an approximate solution for a regular lattice. Our results are able to reproduce most of the experimental findings that have been observed in the literature. In particular, we observe how an increase in the size disparity of the filler particles dispersed in the matrix as well as an aincrease of their aspect ratio decreases the percolation threshold.