Supramolecular double networks of cellulose nanofibrils and algal polysaccharides with excellent wet mechanical properties

Supramolecular double network films, consisting of cellulose nanofibrils (CNF) entangled with the algal polysaccharides alginate or carrageenan, were prepared to achieve water-resistant CNF nanopapers with excellent mechanical properties in both the wet and dry states following the locking of the structures using Ca²⁺.