干混法制备阳离子淀粉工艺方法研究

Study on Preparation of Cationic Starch under Dry Process

用醚化剂GTA与玉米淀粉在不加碱或只加催化量碱的情况下 ,进行反应以制备低取代度阳离子淀粉 ,研究了反应温度、反应时间、体系pH值、体系含水量、GTA用量对取代度、反应效率的影响。在不加碱的情况下 ,当淀粉的用量 9.6g ,GTA的用量 0 .4g,反应时间 3h ,温度控制在 5 0℃ ,制得低取代度阳离子淀粉。所得的产物的取代度为 0 .0 379,反应效率为 85 .2 %。其他条件不变 ,体系中加入 2 .5mLpH值为 9的水溶液 ,所得的阳离子淀粉的取代度为0 .0 387,反应效率为 86.8%。

This paper discussed the preparation of low degree of substitution cationic starch in no alkali or a little alkali condition under dry process.It has been discussed the effect of reaction temperature,reaction time,systematic pH value,hydrous quantity,amounts of glycidyl trimethyl ammonium chloride (GTA) on the degree of substitution ( DS ) of product and reaction efficiency.In no alkali condition,the optimun conditions were:starch 9.6g,GTA 0.4 g,reaction time 3h,temperature 50℃, DS =0.037 3,reaction efficiency 85.2%.If these conditions don't change,furthermore adding aqueous solution 2.5mL,which its pH value is 9,then it's DS =0.038 7,reaction effciency 86.8 %.