Extremely Tough Hydrogels with Cotton Fibers Reinforced

Creating both strong and tough hydrogel materials have been a challenging task, due to their nature of generally mutual exclusion. Interestingly, natural materials such as bone and shells usually offer an unprecedented combination of strength and toughness, which would provide inspiration for novel materials. Herein, the design of natural cartilage is mimicked with collagen fibers incorporated into extracellular matrix, and fabric-reinforced composite hydrogels are prepared. The poly (vinyl alcohol) (PVA) hydrogel composite exhibits significant improvement in the mechanical properties, compared with cotton scaffold or neat PVA gel. Under deformation, the fibers in the hydrogel network are pulled out and break up gradually to dissipate energy, providing significant stiffness and toughness for the gel composite. This work opens up a novel and simple method to construct tough materials and displays potential application in joint-replacement.