Study On Percolation Threshold Of Carbon-based Conductive Polymer Based On Monte Carlo Simulation

With the deep application of carbon-based filled conductive polymer materials in the field of robotic skin,carbon-filled conductive polymer materials with good comprehensive performance have become a research hotspot in the field of material science and information science.Due to the limitation of objective conditions in the experimental study,the structure of conductive network in the filled system can hardly be accurately controlled,leading to the difficulty to reproduce the microstructural changes in macroscopic performance and impossibility to accurate design of sensitive material systems.However,the relevant structural information can be accurately controlled and provided by computational simulation technology.In this work,a three-dimensional simulation model of filled conductive polymer system based on Monte Carlo method is studied.The simulation method is used to analyze the internal correlation mechanism between the structure characteristic parameters of the conductive filler and the percolation characteristics and the percolation threshold of the filled conductive polymer material,which is promising to optimize the design of the carbon-filled system accurately and efficiently.Simulation results provide a theoretical basis for the design of composite conductive materials with high electrical network stability and mechanical network repeatability,which are expected to further expand the application of filled conductive polymers.Based on the theory of percolation and tunnel effect theory,a three-dimensional numerical model was established based on the study of microscopic characteristics of carbon filled polymer system and random distribution of conductive fillers in finite space,taking the advantage that the Monte Carlo method can generate random conformations.The neighbor particle search algorithm based on KD-Tree data structure and the conductive pathway search algorithm based on graph theory are constructed.The effects of the dimensions,content and size of the conductive filler on the percolation characteristics and the percolation threshold of carbon-lack filled,carbon-nanotube filled and hybrid filled conductive polymer system are systematically studied.The mechanism of synergistic conduction between two-phase conductive fillers is revealed,which has important research significance and application value for the flexible electronic skin field.