Simulation-Based Assessment of the Molecular Origin behind Yielding

Solid polymers fail when subjected to high-enough loads. This failure, brittle or ductile, limits the practical use of many commodity and high-tech polymer products. While experimental techniques and phenomenological models are able to provide a macroscopic description of the plastic deformation of polymers in the glassy state, the underlying microscopic mechanisms are to date not well understood. In order to address important design questions, e.g. “Why does atactic polystyrene fails brittle, while polycarbonate fails ductile?”, molecular modeling can be employed to elucidate the origin of plastic deformation in glassy polymers. Particularly, we are interested in shedding light on which aspects of the chemical structure of the polymers have a significant effect on the resulting mechanical (specifically, yielding) behavior. As a prototype system for this study, we are studying atactic polystyrene in the glassy state using molecular simulations. 

Research type: theory/modelling