通过对魔芋葡甘露聚糖进行羧甲基化改性，制备出具有不同取代度的羧甲基魔芋葡甘露聚糖，并确定其最佳工艺条件。利用红外光谱法、差示扫描热量法及电镜扫描对羧甲基魔芋葡甘露聚糖进行表征。结果表明，以取代度为参考指标，魔芋葡甘露聚糖羧甲基改性的工艺条件为：乙醇体积分数为70%，反应体系pH为11.0，醚化温度为50.0℃，醚化时间为3 h，碱化时间为2 h；KGM主链分子上引入了羧甲基基团，其热力学行为被改变，随着取代度的增加，羧甲基魔芋葡甘露聚糖颗粒体积比未改性的大。

Carboxymethyl konjac glucomannan (KGM) with different substitution degrees is prepared by carboxymethyl modification of konjac glucomannan,and the optimal process conditions are determined.A series of characterization studies of carboxymethyl konjac glucomannan are carried out by infrared spectroscopy,differential scanning calorimetry and scanning electron microscopy.The results show that the optimum conditions taking substitution degree as reference index are as follows:volumetric concentration of ethanol is 70%,pH of reaction system is 11.0,etherification temperature is 50.0℃,etherification time is 3 h,and the alkalization time is 2 h.The thermodynamic behavior is changed because the carboxymethyl groups are added into KGM backbone molecules.With the increase of the substitution degree,the volume of carboxymethyl konjac glucomannan particles is larger than that of unmodified ones.

方坤(1992-),男,硕士研究生,研究方向为多糖结构修饰与功能材料,774025180@qq.com