Superabsorbency, pH-Sensitivity and Swelling Kinetics of Partially Hydrolyzed Chitosan-g-poly(Acrylamide) Hydrogels

Authors : Ali POURJAVADI, Gholam Reza MAHDAVINIA

Pages : 595-608

View : 20 | Download : 4

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Acrylamide insert ignore into journalissuearticles values(AAm); monomer was directly grafted onto chitosan using ammonium persulfate insert ignore into journalissuearticles values(APS); as an initiator and methylenebisacrylamide insert ignore into journalissuearticles values(MBA); as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-polyinsert ignore into journalissuearticles values(acrylamide); insert ignore into journalissuearticles values(chitosan-g-PAAm); with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution insert ignore into journalissuearticles values(0.15 mol/L NaCl, CaCl2 and AlCl3); was examined. Swelling capacity of the chitosan-g-PAAm hydrogels in CaCl2 and AlCl3 solutions was higher than that of its hydrolyzed chitosan-g-PAAm insert ignore into journalissuearticles values(H-chitosan-g-PAAm); hydrogels. It was also indicated that the chitosan-g-PAAm and H-chitosan-g-PAAm hydrogels had different swelling capacities in various pHs. The latter hydrogel showed a pH-reversible property between 3 and 10. The swelling kinetics of both hydrogels were found to obey second-order kinetics.
Keywords : Chitosan, polyacrylamide, hydrogel, superabsorbent, pH reversibility, swelling behavior