Strain-Stiffening polymer networks as advanced biomimetic materials

Strain-stiffening is a natural phenomenon exhibited by biopolymer networks that constitute soft tissue and cellular cytoskeleton. This unique mechanical property of biopolymers is a consequence of their inherent semi-flexibility and the network architecture that controls its interconnectivity. Often at large strains, the network microstructure becomes increasingly important in regulating the mechanical behavior of biomaterials. Synthetic polymer chains that are flexible in nature, fail to stiffen in response to large strains, and therefore, replicating strain-stiffening behavior in synthetic polymer networks is often challenging. This review highlights various aspects of strain-stiffening in synthetic polymer networks. From discussing the origin of strain-stiffening in biopolymers, to evaluating the network framework of strain-stiffening synthetic materials, to critically reviewing their aptness as potential biomaterials, this review addresses various challenges that persist for the successful transition of synthetic strain-stiffening materials to next-generation biomimetic materials.