【摘要】 采用D -近似最优设计法研究了NaOH质量分数、碱处理时间及温度对制备壳聚糖的影响。结果表明 ,脱乙酰度随着碱液质量分数的增加而出现峰值 ,当碱液质量分数增加时 ,脱乙酰度增加但其速度却在减小 ,当碱液质量分数达到 4 0 %时 ,脱乙酰度达到 90 %左右 ,而后增加碱液质量分数时 ,脱乙酰度反而下降 ;随着反应温度的升高 ,其脱乙酰度几乎线性递增 ,当温度达到 2 0 0℃附近时 ,曲线趋于平直且脱乙酰度达到最大 ;随着反应时间的增加 ,脱乙酰度开始呈线性增加 ,当反应时间超过 5 0min后 ,脱乙酰度有下降趋势 ;在一定碱液质量分数 (40 % )条件下 ,脱乙酰度随着温度的增加而增加 ,但若需获得较高质量的壳聚糖必须提高反应温度更多还原

【Abstract】 This paper reported the study on the effects of three factors (Concentration of NaOH, time of NaOH treatment, and temperature of NaOH treatment) in preparation of chitosan.The concentration of NaOH influences the degree of deacetylation of chitosan to much high extent according to D approximate design experimental method. When the temperature attains 200℃, the degree of deacetylation of chitosan shows a peak value, while it will increase with the concentration of NaOH, and then with the concentration of NaOH increasing, the degree of deacetylation of chitosan will increases hardly. The ascend pace of the degree of deacetylation of chitosan will diminish with the concentration of NaOH increasing, and the degree of deacetylation of chitosan is 90% when the concentration of NaOH attains 40%. The degree of deacetylation of chitosan may descend if the concentration of NaOH is increased further. The degree of deacetylation will increases with the temperature increasing in linearnrity. The curve goes to flat when at 200℃ or so, and the degree of deacetylation of chitosan will reach the maximum.The degree of deacetylation increases in linearity at the beginning, and then it begins to descend when the time exceeds 50 minutes. However it will increase with the temperature increasing at the special concentration of NaOH(40%). So the temperature must be increased if higher quantity of chitosan needs to be acquired.更多还原