Preparation of a superabsorbent polymer by graft copolymerization of corn starch and acrylic acid

By using ceric ammonium nitrate as the initiator,a superabsorbent polymer was prepared from graft copolymer of corn starch and acrylic acid.The influences of the amount of crosslinking agent and initiator,neutralization degree of acrylic acid,reaction temperature and reaction time on the water absorbency of the graft copolymer were investigated.The optimum reaction conditions are(0.95)×10~(-5) molar ratio of crosslinking agent to acrylic acid,(4.8)×10~(-3) molar ratio of initiator to acrylic acid,71% neutralization degree of acrylic acid,polymerization at 45 ℃ and 2 h.Water absorbency in distilled water and tap water in 30 min is about 1000 g/g and 200 g/g,respectively.