Piezoresistive response of graphene rubber composites considering the tunneling effect

The piezoresistive behavior of graphene conductive polymer composites is vital for the performance of smart-sensing materials. In this paper, a numerical method for predicting the piezoresistive properties of graphene rubber composites is established in which user subroutines include the quantum tunneling effect. A representative volume element (RVE) with randomly distributed graphene was constructed, taking into account the large deformation characteristics of the rubber matrix, which accurately predicted the conductivity, the percolation value, and the mechanical properties of the graphene rubber composites. Additionally, the strain sensing behavior of graphene rubber composites was calculated, which was in good agreement with the experimental results. The effects of the curved and crumpled graphene configuration, tunneling effect, and nanoparticle distribution on the piezoresistive response are discussed. These results play an essential role in evaluating and designing advanced smart rubber composites.