为获得制备醋酸酯淀粉的新工艺,采用机械活化固相化学反应法制备木薯醋酸酯淀粉。以醋酸酯淀粉的取代度为评价指标,分别探讨醋酸酐用量、NaOH用量、球磨温度、球磨时间、搅拌速度、球磨介质的堆体积等因素对木薯淀粉醋酸酯反应的影响,并对影响因素进行了正交优化。结果表明:在醋酸酐质量分数60%、NaOH质量分数2.0%、球磨温度60℃、球磨时间60 min、搅拌速度380 r/min、球磨介质堆体积500 mL的反应条件下,制备得到的木薯醋酸酯淀粉的取代度为0.263 2,反应效率为25.57%。并采用红外光谱(FTIR)、X-射线衍射(XRD)对木薯醋酸酯淀粉的结构进行了表征。机械活化对淀粉发生酯反应有显著的强化作用。

In order to develop a new preparation method of starch acetate,the cassava starch acetate was synthesized by mechanical activation-strengthened solid phase chemical reaction.The effects of acetic anhydride content,sodium hydroxide content,ball-milling temperature,ball-milling time,stirring speed and the volume of the stack for ball-milling media on esterification of cassava starch were investigated.The degree of substitution(DS) of starch acetate was used as the evaluating parameter.The best conditions of preparation technique were confirmed by orthogonal test.The optimum conditions of cassava starch acetate preparation were 60% acetic anhydride,2.0% sodium hydroxide,ball-milling temperature 60℃,ball-milling time 60min,stirring speed 380r / min,tack media 500 mL,the DS of the products 0.2632,and the RE was 25.57%.Furthermore,the structure of native starch and the starch acetate were further characterized by using Fourier transform infrared spectrometry(FTIR) and X-ray diffraction(XRD).The mechanical activation considerably enhanced the esterification of cassava starch.