Molecular dynamics simulations of the buckling behavior of defective carbon nanotubes embedded in epoxy nanocomposites

Many investigations have identified buckling of CNTs as a common mode of failure of CNT-reinforced nanocomposites. Several studies have also focused on the influence of defects on the buckling properties of freestanding CNTs. However, it is found that molecular dynamics (MD) based investigations concerned with the buckling of embedded CNTs are rare in the literature. In this research, the effects of various vacancy and Stone-Wales (SW) defect configurations on the buckling behavior of freestanding and embedded single-walled CNTs (SWCNTs) are investigated using MD. The simulations are based on the consistent valence forcefield (CVFF) and performed with the aid of LAMMPS. Our findings revealed different degradation effects and buckling modes for freestanding and embedded SWCNTs. The defects generally have the same influence on the buckling strain of the freestanding and embedded SWCNTs. However, it is found that increasing the number of missing atoms generally reduces the buckling load of freestanding SWCNTs, while increasing it for embedded armchair SWCNTs.