Energy dissipation after the fracture of end-linked polymer networks using molecular simulations

The fracture of end-linked polymer networks and gels strongly affects the performance of these versatile and widely used materials, and a molecular-level understanding of the fracture energy is important to the design of new materials. The Lake-Thomas theory serves as a framework to understand and quantify the energy dissipation due to the chain scission in these materials based on an idealized picture of fracture in networks. Recent extensions of the Lake-Thomas theory have incorporated the effect of topological defects, such as loop defects, and in some examples enabled accurate prediction of the fracture. In this talk, I will describe how we use coarse-grained molecular dynamics simulations and network analysis techniques to provide a molecular view of the energy dissipated during chain scission in polymer networks. In addition to the energy of the broken strand, we also consider the amount of energy released by the networks connected to the broken chain and other sources of energy dissipation due to the fracture process. Our results can be used to further refine the description of the processes at play during the failure of polymer networks.