脱乙酰化反应条件对壳聚糖性能的影响

本文研究了甲壳素在脱乙酰化反应时不同反应条件,如碱浓度、反应时间、反应温度和处理方法对壳聚糖性能,如分子量、脱乙酰化度的影响,探讨了分子主链降解反应与脱乙酰化反应之间的关系。结果表明:随着碱浓度和反应时间的增加,壳聚糖脱乙酰化度提高,而分子量降低;脱乙酰化越高,主链降解程度增加;反应温度升高,脱乙酰化反应速度加快;而采用短时重复多次反应的处理方法,则可增加壳聚糖的脱乙酰化度,并减少主链降解程度。

The Effect of Deacetylating Variables on the Performances of Chitosan

The effect of reaction variables (alkali concentration, time temperature and treatment) on the performances(molecular weight and degree ofdeacetylation) of chitosan was investigated when chitin was deacetylated with alkali, The relation between degrada-tion and deacetylation of chitin was observed in the reaction, It is shown that the higher al-kali concentration and prolonged time increase the degree of deacetylation and reduce molecular size; the higher the degree of deacetylation, the degradation of the molecular chains is more severe; the higher the temperature increases the rate of deacetylation; how-ever, the shortened time and intermittent treatments increase the degree of deacetylation and lower the extent of degradation, The above conclusion will provide scientific basis for the improvement of technological condition in the preparation of chitosan.