微波场中KCl浓度对几丁质脱乙酰反应的影响

研究了KCl浓度对几丁质在微波场中脱乙酰反应的影响. 结果表明，引入盐离子促进了反应的进行. 随着反应时间的延长，几丁聚糖的脱乙酰度上升，但上升速度逐渐变慢，呈一级反应特征；分子量随时间延长而降低. 脱乙酰度随KCl浓度上升而减小，但在实验范围内，均高于对照组. 当KCl]=0.05 mol/L时脱乙酰度达到79.26%，与对照组相比(脱乙酰度=69.84%)提高了13.5%. 随KCl浓度的上升，分子量开始减小，当KCl浓度上升到0.2 mol/L附近时，分子量又呈上升趋势. 这是由于KCl浓度影响体系介质损耗角正切值，在较高KCl浓度时降低了体系对微波的吸收能力.

Influence of KCl Concentration on Chitin Deacetylation in Microwave Field

This paper presents the effect of KCl concentration on chitin deacetylation in the microwave field. The experimental result shows that the reaction was enhanced when salts were introduced into the reaction system. The degree of deacetylation (DD) of chitosan increases with time, but the rate of increase slows down gradually, revealing the characteristics of first order reaction. The molecular weight (MW) of chitosan decreases with time. The DD of chitosan decreases with the increase of the concentration of KCl, but it is higher than that of the control in the concentration range of KCl investigated. When KCl concentration equals 0.05 mol/L, the DD is 79.3%, as compared with that of the control (69.6%). Along with the increase of KCl concentration, the MW of chitosan decreased, but it increased when the concentration was greater than 0.2 mol/L.