壳聚糖丙酮酸衍生物的合成及吸湿保湿性能

摘要

以丙酮酸改性壳聚糖制备了N-(1-羧乙基)壳聚糖(CET),用1H NMR、电位滴定等方式对产物进行了表征.研究发现,丙酮酸与糖元比例、反应时间、pH和壳聚糖相对分子质量(Mw)对产物取代度(DS)影响较大,最佳丙酮酸与糖元比例、反应时间、pH分别为8∶ 1, 8 h, 4.5. 随壳聚糖Mw降低,DS增加. CET比壳聚糖的吸湿保湿明显增加,并呈现与HA类似的吸湿保湿性能.%N-(1-carboxyethyl) chitosan(CET) was successfully prepared from chitosan and pyruvic acid(PA) under reducing conditions, via aldimine formation. The chemical structure of the derivative obtained was determined by 1H NMR. It was found ratio between pyruvic acid and glucose residue(RPT), reaction time, pH and molecular weight(Mw) of chitosan had great influence on the degree of substitution(DS). CET had similar moisture absorption-retention abilities with HA, and much better abilities than the original chitosan.