Swelling Kinetics Study of Hydrolyzed Starch-poly Acrylonitrile Superabsorbent Hydrogel with Salt-sensitivity Properties

Abstract

In this paper, we have focused on study of swelling kinetics and salt-sensitivity behaviour of a superabsorbing hydrogel based on starch and polyacrylonitrile. The physical mixture of starch (St) and polyacrylonitrile was hydrolyzed by NaOH solution to yield hydrogel i.e., St-poly(sodium acrylate-co-acrylamide). The swelling kinetics of the hydrogels with various particle sizes was preliminary investigated as well. The swelling of the hydrogel showed a second order kinetics of swelling in water. In addition, swelling measurements of the synthesized hydrogels in various chloride salt solutions was measured. Results indicated that a swelling-loss with an increase in the ionic strength of the salt solutions.