The Preparation of Chitosan with High Viscosity by Ultrasonic Method
Abstract: This work used cartilage of squid as raw material. After removingcalcium by 6% hydrochloride, removing protein by hot alkali and decolorizing by sodium hypochlorite, and got chitin from Squid pens. Under the condition of ultrasonic wave reaction, through studied the effect of concentration of alkali, temperature and time on deacetylation of chitin and viscosity-average molecular weight. The degree of deacetylation increased as concentration of alkali and temperature increased. Viscosity-average molecular weight decreased as concentration of alkali and time increased. Temperature hardly has any effect. The best condition is as follows: deacetylation by 50% NaOH at 80℃ for 2h. The results showed that the chitosan had the viscosity of 263.98×104and the deacetylate rate up to 92.91% under the optimal reaction condition. Infrared analysis shows that chitosan of Squid pens is β-chitosan.
