甲基二乙醇胺双脂肪酸酯的合成与表征

研究了不同碳链长度的脂肪酸与N-甲基二乙醇胺的酯化反应。以月桂酸为原料,通过正交实验考察了反应温度、物料摩尔比、回流液温度、催化剂用量等因素对该酯化反应的影响,确定了较优的工艺条件为:反应温度200℃,n(月桂酸)∶n(N-甲基二乙醇胺)=1.8∶1.0,回流液温度70℃,催化剂用量(相对于反应原料的质量)0.3%。在该工艺条件下,酯化产物中甲基二乙醇胺双月桂酸酯(双酯胺)的质量分数可达98%以上。并对正辛酸、正癸酸、棕榈酸和硬脂酸与N-甲基二乙醇胺的酯化反应条件进行了优化,得到的产物中双酯胺的质量分数达98%以上。采用IR和1HNMR对双酯胺的结构进行了表征。

Synthesis and Characterization of Methyl Diethanolamine Fatty Acid Di-ester

The esterification reactions between the fatty acids with different alkyl chain length and the N-methyl diethanolamine were investigated. The reaction conditions were optimized by orthogonal experiments with lauric acid as materials. The effects of reaction temperature, catalyst dosage, molar ratio of raw materials and reflux temperature on the esterfication were examined, and the optimized reaction condition were determined as following: reaction temperature of 200 oC, catalyst dosage of 0.3%(mass ratio of catalyst/total raw materials), n(lauric acid) : n(N-methyl diethanolamine)=1.8:1, reflux temperature 70 oC. Under the optimized condition, the mass fraction of methyl diethanolamine lauric acid di-ester in the product was more than 98%. In addition, the conditions of esterification reactions between the fatty acids with different alkyl chain length and N-methyl diethanolamine were optimized. Under the optimized condition, the mass fraction of fatty acid diethanolamine di-ester in all of these products was greater than 98%. The products were characterized by IR and 1HNMR.