在氨基酸离子液体中均相合成马来酰化壳聚糖

合成了氯化2-氨基乙酸离子液体(Gly]Cl),由FTIR、1HNMR对其结构进行了确证,并以其质量分数2%的水溶液为反应介质,制备水溶性马来酰化壳聚糖(MACH)。用XRD和FTIR对产物进行了表征,测试结果表明:壳聚糖(CS)中引入了马来酰基,并且反应主要发生在氨基上。考察了反应时间、温度和反应物摩尔比对马来酰化壳聚糖取代度(DS)的影响,得到较佳反应条件为:n(马来酸酐)/n(壳聚糖)=2.5、反应温度60℃,反应时间5h,在该条件下马来酰化壳聚糖的取代度达90%以上。离子液体Gly]Cl具有重复使用性,反应后的离子液体未经处理重复使用3次后,马来酰化壳聚糖的取代度仍大于89%。

Synthesis of Maleyl Chitosan in Amino Acid Ionic Liquid

Gly]Cl ionic liquid was synthesized and its structure was confirmed by the IR and 1HNMR.Maleyl chitosan (MACH) was prepared by the homogeneous reaction in the Gly]Cl ionic liquid aqueous solution of which weight percentage is 2%.The structure was characterized by XRD and FTIR.The results indicated that OCHCHCOOH was introduced to the —NH2 of chitosan molecule.The influence of reaction time,temperature and the mole ratio of maleic anhydride and the amino group of chitosan on the degree of substitution were investigated respectively.The optimum conditions were obtained as follows:n(maleic anhydride)/n(chitosan)=2.5,reaction temperature 60 ℃ and reaction time 5 h,the degree substitution of maleyl chitosan was over 90%.The repeating usage of the ionic liquid was also investigated.Furthermore,Gly]Cl could be reused 3 times without any disposal and the degree substitution was still above 89%.