Deformation of glassy polycarbonate and polystyrene: the influence of chemical structure and local environment

Understanding the mechanism of deformation is very important in various applications. Although the stress-strain behavior of crystals and glasses are similar, the mechanism of deformation is very different. We used molecular dynamics to study polycarbonate and polystyrene under constant external loads. The results indicate that high atomic/segmental mobility and low local density enable the formation (nucleation) of highly deformed regions that grow to form plastic defects, and the effect of chemical structure was found to dominate the deformation mechanism