Molecular Modeling and Mechanics of Acrylic Adhesives on a Graphene Substrate with Roughness

Understanding the mechanics of amorphous polymeric adhesives on a solid substrate at the fundamental scale level is critical for designing and optimizing the mechanics of composite materials. Using molecular dynamics simulations, we investigate the interfacial strength between graphene and polyacrylic and discuss how the surface roughness of graphene affects the interfacial strength in different loading directions. Our results show that a single angstrom increase in graphene roughness can lead to almost eight times higher shear strength, and that such result is insensitive to compression. We have also revealed that the graphene roughness has modest effect on tensile strength of the interface. Our simulations elucidate the molecular mechanism of these different effects in different loading conditions and provide insights for composite designs.