Solution Properties of Partially Hydrolysed Polyacrylamide and Chitosan Mixed Solutions

Summary: In this paper, the properties of a partially hydrolysed polyacrylamide with a low charge density and chitosan mixtures were evaluated in an aqueous acid solution. The formation of a soluble complex was followed by conductometry and potentiometry, and the stoichiometry at the titration endpoint was investigated as a function of the polyanion added. The influence of salts on the titration endpoint and on the rheological behavior of the mixed solutions was also studied. The mixture of equal concentration of both polymers, in the absence of salt, presented synergy, with a significant viscosity increase. Nevertheless, in the presence of salts, this mixture presented minimum viscosity. These results were discussed as a function of the polymers structural features and the environment used in the study.