利用溶液聚合法制备了壳聚糖接枝聚丙烯酸钠/高岭土复合树脂,研究了复合树脂在蒸馏水中的吸水速率、重复吸水性能和人工尿液中的吸水倍率,以及在不同温度、不同电解质溶液离子强度和不同pH值的环境下复合树脂的吸水性能。结果表明,复合树脂的吸水速率较慢,在多次重复吸水后吸水性能也逐渐降低,在人工尿液中的吸水倍率高于聚丙烯酸钠树脂,低于壳聚糖接枝丙烯酸钠树脂;随着温度的升高,复合树脂的吸水能力增强,超过50℃后变化较小;树脂的吸液倍率随着电解质溶液浓度和价态的增大而下降;随着pH值的增大而出现驼峰,在pH=3.5和pH=8.5处分别出现吸液倍率最大值。
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.