The phase state and rheological properties of chitosan-acetic acid-water system

The phase state and rheological properties of the chitosan-acetic acid-wate r ternary system were studied over a wide composition range. The proportion of acetic acid was shown to affect the solvent power, viscosity, viscous-f low activation energy E-a, and stability of dilute and concentrated chitosa n solutions in a nonmonotonic manner. The maximum intrinsic viscosity was o bserved for solutions in 10% acetic acid, hut the relative and the dynamic viscosity of semidilute (1-3%) solutions show maximum values for acetic aci d concentrations of 2 and 70-77%. Reasons for the observed behavior are dis cussed.