Rate-Dependent Damage Mechanics of Polymer Networks with Reversible Bonds
Samuel C. Lamont, Jason Mulderrig, Nikolaos Bouklas, Franck J. Vernerey
Abstract
Dynamic polymer networks utilize weak bonding interactions to dissipate the stored energy and provide a source of self-healing for the material. Due to this, tracking the progression of damage in these networks is poorly understood as it becomes necessary to distinguish between reversible and irreversible bond detachment (by kinetic bond exchange or chain rupture, respectively). In this work, we present a statistical formulation based on the transient network theory to track the chain conformation space of a dynamic polymer network whose chains rupture after being pulled past a critical stretch. We explain the predictions of this model by the observable material timescales of relaxation and self-healing, which are related to the kinetic rates of attachment and detachment. We demonstrate our model to match experimental data of cyclic loading and self-healing experiments, providing physical interpretation for these complex behaviors in dynamic polymer networks.