Cavitating Gels: Macroscale Failure to Molecular Structure

Failure, or fracture, remains one of the most important, yet most challenging, topics in materials science. This challenge is especially true for soft materials, such as hydrogels and biological tissues. Understanding failure in these systems is critical for developing important technologies, from robust prosthetic materials to protective gear for mitigating debilitating injuries. However, the ultra-soft nature of these materials makes quantifying failure processes difficult. Here, I present recent advances in understanding how cavitation-based deformations lead to either reversible or irreversible damage in model polymer gel materials. These advances were developed as a result of a multi-university, multi-disciplinary study that combined the use of precisely-defined polymer networks, molecular dynamic simulations, and new characterization methods to develop and validate theoretical relationships between molecular architecture and macroscale cavitation and fracture. Collectively, these results enhance fundamental understanding of ultra-soft gel materials and the mechanisms that control their failure across a range of size scales.