Molecular Dynamics prediction of elastic and plastic deformation of semi-crystalline polyethylene

The plastic deformation of a semi-crystalline polyethylene is predicted by a molecular dynamics method. A full-atom model is able to predict the correct amorphous and crystalline phases. Two high molecular weight molecules are involved in these two phases with 3D-periodic conditions. This is one of the first fully coupled model including the main features of the molecular organization. A tensile experiment is applied on the molecular system perpendicular to the lamellae surface. The deformation mechanism inside the amorphous and crystalline phases, and the force evolution, are detailed. This analysis is able to check the effect of details of molecular structure in the amorphous phase on the solid-state rheology. Moreover, a cavitation appears very early in the amorphous phase for all the simulations.