Degradation of chitosan and chemically modified chitosan by viscosity measurements

Abstract

AbstractChitosan and chitosan‐grafted‐acrylamide were subjected to degradation in the presence and absence of a degrading agent at 37°C by measuring the viscosity of polymer solutions. Extracts from the fresh rat droppings were used as the degrading agent to simulate the environmental degrading conditions. Results of this study indicated that the concentrations of acetic acid in solution and chemical modifications of chitosan affected the degradation both in the presence as well as in the absence of a degrading agent. Reduction in viscosity was used to study the degradation. Chitosan was stable up to sixteen days of immersion in acetic acid without the degrading agent, but it readily underwent degradation in the presence of a degrading agent. Chitosan‐grafted‐acrylamide also followed the same trend, but the extent of reduction in viscosity was much less than pure chitosan, indicating that the chemical modification has improved the stability of the polymer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3255–3258, 2006