Chemically fueled covalent crosslinking of polymer materialsElectronic supplementary information (ESI) available: Experimental details, supplemental characterization of polymers, additional rheological and infrared data. See DOI: 10.1039/c8cc09823a

Transiently crosslinked dynamic polymer networks are developed, using carbodiimide hydration to link carboxylic acids as anhydrides. From aqueous polymer solutions, non-equilibrium hydrogels are transiently formed, which dissolve upon anhydride hydrolysis. The materials can be refueled using a subsequent injection of carbodiimide. The gels exhibit higher storage moduli compared to transient supramolecular gels as a result of their covalent crosslinks. Non-equilibrium covalently crosslinked hydrogels are synthesized using carbodiimide fueled coupling of carboxylic acids to anhydrides which eventually dissipate by hydrolysis.