Viscometric Properties of Carboxymethylchitosan Solutions

Abstract

The viscosity of carboxymethylchitosan solutions was measured via an Ubbelohde viscometer. The effect of carboxymethylchitosan concentration, pH of the carboxymethylchitosan solution, and concentration of added NaCl and CaCl 2 on the reduced viscosity of the carboxymethylchitosan solutions were comparatively investigated. The results showed that the reduced viscosity of the carboxymethylchitosan solution decreased with the increase of carboxymethylchitosan concentration. The reduced viscosity of carboxymethylchitosan decreased with the addition of NaCl and CaCl 2 , and CaCl 2 affected the viscosity more significantly than NaCl. With the increase of pH, the reduced viscosity first decreased and then increased. The interaction between Ca 2+ ions and carboxymethylchitosan was studied by means of dynamic light scattering and scanning electron microscopy.

Studies on Intermolecular Interaction of N-Glycidyltrimethyl Ammonium Chloride Modified Chitosan/N,N-Dimethyl-N-dodecyl-N-(2,3-epoxy propyl) Ammonium Chloride and Curcumin Delivery

“…The reduced viscosity decreases quickly from 0.33 to 0.01 L/mg when the DDEAC concentration is increased from 0 to 8.0 mmol/L, and then with further increasing DDEAC concentration to 90 mmol/L, the reduced viscosity reduces slightly. The phenomenon is typical for polyelectrolyte solutions [ 37 ]. It is known that the reduced viscosity of pure polyelectrolyte solution decreases while its concentration is increased, because the macromolecular chains are expanded at a low concentration, and are overlapped at a high concentration [ 37 ].…”

“…The phenomenon is typical for polyelectrolyte solutions [ 37 ]. It is known that the reduced viscosity of pure polyelectrolyte solution decreases while its concentration is increased, because the macromolecular chains are expanded at a low concentration, and are overlapped at a high concentration [ 37 ]. For GTA-m-CS/DDEAC system, the decrease of reduced viscosity is ascribed to the adsorption of DDEAC on GTA-m-CS, and the decrease of intermolecular repulsion.…”