Universal and Green Strategy for Super-Tough Citrate-Based Polymers via Strong Hydrogen Bonds

Citrate-based biodegradable elastomers face significant practical limitations due to their inherently poor mechanical properties. While existing enhancement strategies can partially address this issue, they often rely on toxic catalysts or damage inherent material advantages. Here, we establish strong hydrogen bonds in the cross-linked networks of citrate-based polymers by a PBS impregnation method to improve their mechanical properties. Based on the strategy, poly(1,8-octanediol-co-citrate) can increase its toughness by 109-fold, transforming it into a bioplastic with mechanical characteristics superior to those of polylactic acid. Moreover, the strategy demonstrates universal applicability across the family of citrate-based polymers while preserving intrinsic specialties and advantages.