Electrical Properties Of Carbon Black/Graphene Filled Composites Based On Monte Carlo Method

With the continuous development of carbon black/graphene filled conductive composites in the field of wearable electronic devices and robots,how to make materials have the characteristics of high performance and low cost has gradually become a research hotspot in the field of materials science.In the process of experiment,it is difficult to accurately control the micro conductive network in the composite,and the accurate design of the composite system is difficult to achieve.Therefore,the computer simulation technology is used to provide detailed micro information by modeling the micro network inside the composite.Generating RVE(Representative Volume Element)is the first step in simulation,but the lack of systematic research on RVE results in low simulation accuracy and reliability.In this work,a study of the appropriateness,geometry,size,and fillers boundary restraint on RVE for conductive nanocomposites filled with single filler of carbon nanotubes,carbon black or graphene nanoplatelets is studied.The results show that it is reasonable to use RVE in the simulation.The cube is suggested as the standard shape of RVE and the size of RVE can determine by the Chi-square test results obtained from percolation threshold.It is also concluded that periodic and aperiodic boundary restraint are superior to truncated boundary restraint.This study can provide the theoretical and technique foundation for reasonably setting RVE parameters and accurately predicting the electrical properties for nanocomposites filled with different dimension fillers.Then the electroosmosis of carbon black/ graphene nanoplatelets filled composite was studied in this paper.Firstly,the influence of packing particle size on the electroosmotic flow of single packing is discussed.Then,based on the three-dimensional model and parameters of carbon black and graphene nanoplatelets,the nonlinear synergistic enhanced conductivity effect NSECE and the conditions affecting the formation of NSECE were studied.The results show that the reason for NSECE is that the networking capabilities of carbon black and graphene nanoplatelets are different.When the diameter of carbon black is much smaller than the side length of graphene nanoplatelets,the electrical properties of carbon black and graphene nanoplatelets filled hybrid nanocomposites are more likely to exhibit NSECE.