以玉米淀粉为原料,3-氯-2-羟丙基三甲基氯化铵(CTA)为醚化剂,在碱性条件下,采用半干法制备低取代度阳离子淀粉。采用Box-Behnken中心组合响应面设计,对半干法工艺进行优化,并分析反应温度、反应时间、碱的用量、体系含水量对阳离子淀粉取代度的影响。结果表明:回归方程能较好地预测取代度随工艺条件变化的规律,半干法制备低取代度阳离子淀粉工艺条件为:反应温度64.40℃,反应时间6.58 h,NaOH与醚化剂摩尔比2.12,体系含水量25.28%,在此条件下制得的阳离子淀粉取代度为0.051 9。

The cationic starch with low degree of substitution was half-dry prepared from corn starch,CTA and NaOH.The preparation of cationic starch were optimized by response surface methodology(RSM),based on a Box-Behnken design.The effects of the reaction temperature,the reaction time,the ratio of NaOH and CTA,the water content were explored.Regression coefficient and variance analysis showed that the regression model fits the actual process well.The optimum technology conditions were confirmed as followings: the reaction temperature 64.40℃,the reaction time 6.58 h,the ratio of NaOH and CTA 2.12,the water content 25.28%,the degree of substitution was 0.0519.