Preparation of High Water Absorption and Retention Material by Graft Copolymerization of Calcium Lignin Sulphonate with Acrylic Acid and Acrylamide

High water absorption material was prepared by graft copolymerization of calcium lignin sulphonate with acrylic acid and acrylamide. Effect of process parameters on graft copolymerization and sample properties was investigated by means of the single-factor method, and the microstructure of fracture surface of the water absorbent resin was analyzed by SEM. The result shows that: when mass percents of acrylic, acrylamide, calcium lignin sulphonate, initiator and crosslinking agent are 65.5%, 19.5%, 15%, 0.09%, and 0.05%, respectively, and neutralization degree is 60% with 2h of initiation reaction time and 1.5h of crosslinking reaction time. The water absorption rate of material is up to 1010g/g, and 0.9wt% NaCl solution absorption rate is up to 110g/g.