Combination of acid treatment and dual network fabrication to stretchable cellulose based hydrogels with tunable properties

Cellulose based hydrogels with a relatively high stretchability were fabricated in the NaOH/urea system via sequential chemical crosslinking and dual network fabrication. The first step involved crosslinking of cellulose using epichlorohydrin as a crosslinker. Cryo-electron microscopy analysis revealed the utilization of diluted acid to treat hydrogels significantly affected the morphology of the first network and improved the mechanical properties. After diffusion of precursors into the first network, the dual network hydrogels were generated after the UV light-initiated polymerization.