RESUMO
Water-soluble carboxymethyl chitosan was prepared from dried shrimp shells. The intrinsic viscosities of its samples were measured to evaluate the stability of carboxymethyl chitosan. The influential factors of stability, such as heat, pH, ionic strength, ultraviolet radiation, and sterilization were studied. The results demonstrate that the intrinsic viscosities of water-soluble chitosan will be influenced, to a certain extent, by the change of pH and ionic strength. Ultraviolet radiation and sterilized processes not only exept influence on the degradation of chitosan, but also have prominent effects on the molecular structure of it. Besides, temperature will also affect the speed of degradation, and chitosan can be stored at a temperature as low as 2 degrees C-8 degrees C.