Preparation of polyacrylic acid IPN hydrogel

Using acrylic acid as monomer,N,N'-methylene bisacrylamide as crosslinking agent,ammonium persulfate as initiator,polyacrylic acid IPN hydrogel was prepared through free radical polymerization. The influence of crosslinking agent,initiator,neutralization degree,polymerizing temperature and salt solution on swelling behaviors was investigated. The results indicated that when the mass of initiator was 0. 6% of monomer,crosslinking agent was 0. 8%,and neutralization degree was 70%,the swelling property of the IPN hydrogel was optimal,and the water adsorption achieved more than 3 000%. The swelling property of the polyacrylic acid IPN hydrogel decreased with the increasing of salt solution concentration.