N,O-羧甲基壳聚糖制备工艺的优化研究

Study on Optimization of Craft of Preparing N,O-carboxymethylated Chitosan

通过综合分析目前国内外制备N ,O 羧甲基壳聚糖工艺现状和反复对比试验,确定了制备N ,O 羧甲基壳聚糖的优化新工艺,即以壳聚糖为基本原料,以异丙醇作溶胀剂,采用在不同温度段添加不同碱量的制备方法,将最佳投料比定为w(壳聚糖)∶w(一氯乙酸)∶w(氢氧化钠) =1∶4 .8∶5 ,最佳羧化反应时间定为4h ,最佳反应温度定为6 0℃,结果与传统制备工艺相比,产品的羧化度提高了0 .4 7,收率提高了7% ,制备成本下降12 %以上,主要经济技术指标均优于传统制备工艺。

This paper confirmed the optimal craft of preparing N,O-carboxymethylated chitosan, by a great deal of information about preparing N, O-carboxymethylated chitosan in the world. This optimal craft included that rate of reactant's weight was w(chitosan):w(ClCH2COOH):w(NaOH) = 1:4.8:5, and its optimal reacting temperature was 60°C, its optimal reacting time was 4 h, using chitosan as a basic reactant, using iso-propyl alcohol as a solvent, adding the different deal of NaOH to reactants on the different temperature stage. Compared with traditional craft, the carboxylated degree of this product had enhanced 0.47, yield had enhanced 7%, and the cost of preparing this product had cut down more than 10%, the main economic and technical indexes of this product were all superior to traditional one made from traditional craft.