水相中高取代度低黏度羧甲基淀粉的制备

羧甲基淀粉(CMS)是一种阴离子淀粉醚,广泛应用于医药、食品、纺织、石油钻探等领域。以玉米淀粉为原料,采用酸化-醚化复合变性的方法在水相中制备高取代度低黏度羧甲基淀粉(CMS),探讨了酸化时间、液固比、NaOH用量、ClCH2COOH用量、醚化反应时间、反应温度对羧甲基化过程的影响,研究发现,对原淀粉进行酸化,可以在不增加其它反应试剂用量的基础上提高产物的取代度(DS),但是酸化时间不应过长。同时得到了其他单因素变化时各自对产物取代度的变化趋势,为进一步优化反应条件提供了依据。

Preparation of carboxymethyl starch with high degree of substitution and low viscosity in aqueous media

Carboxymethyl starch(CMS)is a kind of anion starch ether, which is widely used in many fields such as pharmaceutical, food, textile, oil drilling industry and so on. In this article, high DS and low viscosity carboxymethyl starch was prepared in aqueous media through the reaction between corn starch with acid treatment and etherifying agent, the effect of acid treatment time, liquor/material ratio, the amount of sodium hydroxide, the amount of monochloroacetic acid, etherification time, and reaction temperature on the carboxymethylation process was discussed. It shows that DS increases through prolonging the acid treatment time but without adding additional reactant agents, but the duration of acid treatment should be in a proper range. The effect of other factors on the DS was also obtained, which laid good foundation for further optimizing process conditions.