Multiscale study of influence of interfacial decohesion on piezoresistivity of graphene/polymer nanocomposites

Abstract

A multiscale strategy is proposed to study the role of interfacial decohesion on the piezoresistive properties of graphene/polymer nanocomposite. A cohesive zone model is identified by atomistic simulations. This cohesive zone model enriches imperfect interfaces, which model graphene sheets, at mesoscale in our continuum mechanical model. This nonlinear mechanical model is used to generate deformed representative volume element to study influence of strain and interfacial decohesion on the conductivity of graphene/polymer nanocomposites. The effective conductivity is studied with an electric continuum model at mesoscale that incorporates the tunneling effect. A conductor-insulator transition is observed for elongations above 2% for graphene volume fraction just above the percolation threshold. The transition appears for an elongation of 8% instead of 2%, when the interfacial decohesion is removed.

Identification of elastic properties of interphase and interface in graphene-polymer nanocomposites by atomistic simulations

“…The influence of these geometric changes on the yield stress and toughness of the GNP polymer nanocomposite is not obvious. In our opinion, it would merit special study because of deformation mechanism such as cavitation [17] or crazing [91]. The Table 3 summarizes all the conclusions resulting from this discussion, giving the supposed influence of changes in interface properties and geometry on the effective properties of GNP polymer nanocomposites.…”

“…c). The initial system is prepared from the off-lattice self-avoiding random walk combining the simultaneously molecular dynamics relaxation [91]. We assume that the particles interact through the DREIDING potential energy function [92], where the electrostatic contributions are neglected for simplicity reasons.…”

Numerical modeling and experimental characterization of the AC conductivity and dielectric properties of CNT/polymer nanocomposites

“…The nonlinear tunneling effect conduction has been described in details in [32], and has been introduced to several works concerning the electric properties of nanocomposites [33,34]. Considering the tunneling effect in the extremely thin polymer film between the neighbouring CNTs, the current density in the matrix j(x) satisfies:…”

Electromechanical Behaviors of Graphene Reinforced Polymer Composites: A Review

“…Lu et al [148] proposed a multiscale model to study the role of interfacial debonding on the electromechanical behaviors of GRPCs. Atomistic simulation is used to model the cohesive zone.…”