Effect of GNPs debonding on mode I fracture toughness of polymeric nanocomposites

One of the most important applications of nanomaterials in polymer resins is to achieve high fracture toughness even in small volume fractions of filler nanoparticles. Such performance is related to energy released through damage mechanisms that occur at the nano scale. Among these mechanisms, nanoparticle surface separation is more important. In the present work, considering the hierarchical structure of nanocomposites, it has been tried to investigate the effect of debonding of graphene nanoparticles from the surrounding resin on the fracture toughness of the first mode of the presented epoxy/graphene nanocomposite using a multi-scale method. Therefore, a representative volume element has been selected and using the data available in the experimental works of other researchers, the effect of several parameters such as Young's modulus, weight fraction and dimensions of nanographene was investigated. Finally, it was observed that the fracture toughness has a direct relationship with the Young's modulus of the nanocomposite. Also, the smaller the dimensions of the nanoparticles used, the greater the improvement in the fracture toughness.