The physical chemistry of mechanoresponsive polymers

Stretching a polymer can accelerate chemical reactions of its monomers by many orders of magnitude. Exploiting such effects may enable materials scientists to engineer a material's response to mesoscopic loads at the single-monomer level. Such mechanochemical coupling underlies diverse phenomena including the operation of actuating polymers, the catastrophic failure of strained materials, the behaviour of polymer flows and chemical mechanosensing. Yet, our conceptual understanding of this coupling, which cannot be described either by continuum mechanics or chemical kinetics alone, is very limited. A general, physically sound and quantitative model to relate structural distortion at any length scale to reaction rates is needed to facilitate the design of new mechanoresponsive polymers. This article reviews the state-of-the-art recent efforts to understand the physical chemistry of such polymers, particularly the effect of mechanical loads on the reactivity of its building blocks.