Synthesis and characterization of a novel superabsorbent polymer of N,O-carboxymethyl chitosan graft copolymerized with vinyl monomers

A novel superabsorbent polymer was prepared by graft copolymerization of sodium acrylate and 1-vinyl-2-pyrrolidone onto the chain of N,O-carboxymethyl chitosan. The molecular structure of the product was confirmed by FTIR. The surface morphologies before and after the polymerization were examined by SEM. By studying the water absorption of the polymer synthesized under different conditions, the optimal conditions for synthesizing the polymer with the highest swelling ratio was defined. We showed that the water absorption rates of the prepared polymers were high, the swelling processes of the polymers showed first-order kinetics, and the swelling ratio of the polymer was pH dependent.