密闭条件下微波场中甲壳素脱乙酰反应的条件研究

Effects of Various Factors on Chitin Deacetylation under Microwave Irradiation in Sealed Container

密闭条件下微波场中研究反应条件对甲壳素脱乙酰反应的影响.结果表明:120℃时,反应18min,脱乙酰度已超过90%,特性黏度达到440mL/g左右.随料液比的增加,壳聚糖的脱乙酰度及特性黏度增大,但料液比超过1∶20,脱乙酰度和黏度反而都有下降的趋势.原料粒径在0.36～0.60mm之间较好.乙醇辅助处理可提高产物脱乙酰度.经红外光谱测定得出,微波处理及常规方法制备得到产物的分子结构基本相似.

The effects of various factors on the deacetylation of chitinalkali solution in sealed container under microwave irradiation were studied.When temperature was 120℃, the degree of deacetylation of chitosan was more than 90% in 18min.The degree of deacetylation of chitosan decreased with the increase of chitin and NaOH solution ratio. When the ratio was more than 1∶20, the degree of deacetylation of chitosan and intrinsic viscosity decreased gradually. It was ~advantageous for the reaction if the grain size of chitin was 0.36～0.60mm. The results of ~reaction assisted by ethanol showed that degree of deacetylation of chitosan could be increased readily IR study showed that the molecular structure of chitosan was similar with that prepared by the traditional method.