Study on the preparation of the chitosan graft poly (acrylic acid) superabsorbent polymer

Acrylic acid was graft polymerized onto the chain of chitosan, initiated with ammonium persulfate. After crosslinked with N,N'-methylene diacrylamide, a kind of novel superabsorbent polymer was prepared. The structure of the polymer was characterized through FT-IR and SEM. Influence of the reaction conditions on the swelling ratio of the polymer was studied. It is found that the optimization condition to synthesize the polymer with the highest swelling ratio is as follows: m(AA)/m(CTS) = 10, the mass ratio of the initiator and the crosslinking reagent to acrylic acid is 3.3% and 0.16% respectively, the reaction temperature is 65°C and the reaction time is 5.5 h. The polymer synthesized at this condition can absorb 1180 times distilled water and 120 times normal saline.