Preparation and study on the volume phase transition properties of novel carboxymethyl chitosan grafted polyampholyte superabsorbent polymers

A series of promising and novel polyampholyte superabsorbent polymers (CMCTS-g-P(AA-co-LCADMAAC)) were prepared using carboxymethyl chitosan (CMCTS) as skeleton accompanied with graft copolymerization of acrylic acid (AA) and long-chain alkyl dimethyl allyl quaternary ammonium salts (LCADMAAC). The structure of LCADMAAC and prepared superabsorbent polymers were characterized. The optimal conditions for synthesizing polyampholyte polymers with the highest swelling ratio was identified by examining the equilibrium swelling ratio of the polymer prepared under different conditions. Moreover, the unique volume phase transition properties of these polyampholyte superabsorbent polymers were studied. The effects of pH, ionic strength and the ratio of alcohol/water mixture solution on the water absorbency of the polymers were determined.