Molecular Dynamics Studies of Load Transfer in Nanocomposites Reinforced by Defective Carbon Nanotub

This study is concerned with the development of relatively more accurate numerical simulations than those adopted in the literature to investigate the considerable discrepancies between experimental findings and theoretical predictions of the interfacial shear strength (ISS) of nano-reinforced thermoset composites. In this work, extensive molecular dynamics (MD) simulations were conducted to examine the ISS and buckling behavior of carbon nanotube (CNT)-reinforced epoxy composites. We considered different types of defects such as vacancy, Stone-Wales defect, carbon adatom, and phenyl functional group. Pull-out and compressive load simulations were performed via the consistent valence forcefield (CVFF) on a representative volume element comprising a single-walled CNT embedded in an epoxy matrix. Our results revealed that different defects can, to some extent, either enhance or degrade the properties of nanocomposites. The findings will assist in improving our understanding of the toughening/weakening mechanisms associated with nanoscopic reinforcement and the load transfer capability in epoxy-based nanocomposites.