Multiscale investigation of debonding behavior in anisotropic graphene-polyethylene metamaterial nanocomposites

The first phase of this study aimed to validate multi-scale approaches based on Representative Volume Elements (RVEs) for graphene-polyethylene nanocomposites. stress-strain curves of experimental results were compared with numerical homogenization results. The stress amplification obtained from these simulations was used to predict GNP aspect ratios, demonstrating good agreement with permeability results. After validation of the multiscale approach, this study investigates the adhesion between nanoparticles and matrix in anisotropic GNP-HDPE metamaterial nanocomposites, emphasizing the role of the carboxyl (COOH) functional group in improving adhesion. The RVE model is used to investigate the debonding initiation and progression in these anisotropic nanocomposites under tensile and shear loading. Results indicate a variance in debonding onset and growth depending on orientation relative to the GNP axis. In tensile loading, debonding initiates at higher strains along the GNP axis than perpendicularly. Under shear loading within an anisotropic distribution, debonding behaviour varies significantly between planes perpendicular and parallel to the GNP axis. GNP surfaces with fully debonded surfaces slightly exceed 0.6% perpendicular to the GNP axis but increase to over 10.5% parallel to it.