A polymeric material is subject to mechanical loads throughout its lifetime. Its response to such loads spans many orders of magnitude in length and time, from the familiar changes in the shape (bending, stretching, compression) at the macroscopic level all the way to changes in the kinetic stabilities of individual chemical bonds. The latter remains the least understood component of the complex hierarchy of processes that are triggered when a polymeric material is loaded. Yet abundant empirical evidence suggests that the resultant load-induced chemistry plays a critical role in surprisingly diverse applications, ranging from the operation of bulletproof vests, high-performance lubricants and polymer additives widely used in oil and gas drilling, to the behavior of tires, adhesives and water-desalination membranes, to the dynamics of polymer extrusion and ink-jet printing of polymer solutions to degradation of surface-anchored proteins in microfluidics. Exploiting the coupling between mechanical loads acting on a polymeric material and the propensity of its monomers to undergo chemical reactions offers the potential to create new stress-responsive and energy-storing materials, including those for autonomous reporting of local internal stresses and for direct conversion of light to propulsion at the micro- and nanoscales.
At present the field largely lacks a conceptual framework within which to generalize the existing empirical observations about the chemical response of soft matter to mechanical loads or to guide our thinking in designing new materials, reactions and processes to exploit the capacity of mechanical loads to affect chemistry within individual monomers. Over the past few years we have focused on developing theoretical, computational and experimental tools to derive a general relationship between macroscopic control parameters that define mechanical loads (e.g., stress and strain tensors) and molecular properties that govern kinetic stabilities of individual monomers.