Chemical tools for investigating the topology of polymer networks

All polymer networks have topological heterogeneities that span various length scales and dictate their bulk properties. Nevertheless, these features have traditionally been difficult to quantify and control. Informed by classical crossover experiments in physical organic chemistry, we have developed experimental methods for the precise counting of cyclic topologies (loops) in polymer networks. These studies have enabled new theoretical advances pertaining to elasticity and the gel point, and have inspired new stimuli-responsive materials that leverage topology as a design principle.