Synthesis of chitosan derivative graft acrylic acid superabsorbent polymers and its application as water retaining agent.

A new superabsorbent polymer was synthesized using amino ethyl chitosan and an acrylic acid by a free radical polymerization. The chemical structure of the superabsorbent polymer was characterized using FTIR, TGA, XRD and solid-state 13C NMR. The results revealed that the acrylic acid was successfully grafted onto the amino ethyl chitosan backbone. As revealed by SEM, a surface with homogeneous and interconnected pore structure was obtained. The influences of different factors (e.g., the initiator, cross-linker and monomer) on the water absorbency of the superabsorbent polymers were investigated. The results indicated that the superabsorbent polymers have a good swelling ability, water evaporation rate, excellent salt tolerance and pH sensitivity. The new superabsorbent polymers have potential as a water-retaining agent.