Polyprotein Cross-linked Hydrogels with High Stretchability, Fracture Toughness and Low Hysteresis

Abstract

It is challenging to realize both high fracture toughness and low hysteresis perfectly in synthetic systems, which restricts the use of stretchable hydrogels in load-bearing applications. Recently, by imbedding the folded polyprotein cross-linker in a percolating random coiled network, Cao et al. demonstrated a highly stretchable hydrogel, which shows low hysteresis(<5%) but achieves high fracture toughness(ca. 900 J/m2). Moreover, the hydrogel shows outstanding anti-fatigue properties with a fatigue fracture threshold of 126 J/m2. The unique network structure breaks the hysteresis-toughness correlation that is usually reported in stretchable and tough hydrogels. This work has been published in the Nature Communications and can be reached at https://doi.org/10.1038/s41467-020-17877-z .