玉米淀粉醋酸酯的研制

Development of Acetate Cornstarch

以玉米淀粉为基料,以冰醋酸和醋酸酐为乙酰化试剂、硫酸为催化剂,制备了玉米淀粉醋酸酯;用红外光谱对淀粉醋酸酯进行了初步表征,并用酸碱滴定法测试了其取代度和乙酰基含量;系统讨论了酯化剂和催化剂等对淀粉醋酸酯的取代度、乙酰基含量的影响。实验结果表明:酯化剂浓度增大,取代度和乙酰基含量增大;当反应温度为50℃,反应时间为6h,冰醋酸和醋酸酐的质量比例为1∶1,催化剂质量分数为0.1%时,取代度、乙酰基含量较高。

Acetate cornstarch was synthesized by using cornstarch as raw material, glacial acetate acid and acetic anhydride as acetylating agent, H2SO4 as catalyst. It was characterized by using IR, and degree of substituted （DS） and content of acetyl of the products were determined. The effects of ratio of reactants on DS and content of acctyl of the products were discussed. The results showed that the DS and content of acetyl increases with increasing of catalysts and acetic acid, acetic anhydride. The product was better when the reaction temperature is about 50 ℃ , reaction time is about 6 hours, and the condensation of catalyst is about 0.1%.