Abstract:

Increasing global demand for improved absorbent materials with biodegradable，non-toxic, antimicrobial, and salt-tolerant properties creates an incentive for research and development of efficient absorbent materials and systems with additional benefits, such as biodegradability or certain biomedical functions.Organic-inorganic superabsorbent composite emerges to meet this demand.Chitosan grafted poly(acrylic acid sodium)/kaolin superabsorbent composite was prepared by solution polymerization in this paper.The absorption rate and repeated absorption properties in distilled water, water absorbency in artificial urine solution, and the influence at different temperatures, electrolyte concentrations and pH values on absorbency properties of the superabsorbent composite were discussed, respectively.The results showed that absorption rate of superabsorbent composite was slower than that of polyacrylic resin and chitosan grafted polyarylic resin and water absorbency decreased with increasing repeat number, and water absorbency in artificial urine solution was higher than poly(acrylic acid）and lower than chitosan grafted poly(acrylic acid).As temperature increased, water absorbency was enhanced, while began to drop after 50℃.Water absorbency of superabsorbent composite decreased simultaneously when ionic strength and valence of electrolyte solution increased.Along with the increase of pH value，the absorption curve showed a hump at pH=3.5 and pH=8.5.According to this study, basic information of absorbency properties about organic-inorganic superabsorbent composite based on chitosan，poly(acrylic acid）and kaolin was provided.