薄膜蒸发合成壬二酸二辛酯

SYNTHESIS OF DIOCTYL AZELATE BY THIN FILM EVAPORATION

以壬二酸和2-乙基己醇为原料、对甲苯磺酸为催化剂,采用薄膜蒸发技术合成了壬二酸二辛酯。测定了产物的酸值、羟值、色泽、倾点及开口闪点,并采用IR、^(1)H NMR及^(13)C NMR表征了产物结构。考察了薄膜蒸发真空条件、催化剂用量、2-乙基己醇和壬二酸摩尔比对酯化反应的影响。结果表明,适宜的反应条件为:真空度为0.06 kPa,催化剂用量为0.5%(占酸和醇总质量分数),醇酸摩尔比为2.8。与传统合成法相比,薄膜蒸发法的酸值达标所需时间缩短了92.5%,羟值达标时间缩短了89.3%,产品色泽较好。

Dioctyl azelate was synthesized by thin film evaporation technology using azelaic acid and 2-ethylhexanol as raw materials and p-toluenesulfonic acid as catalyst.The acid value,hydroxyl value,color,pour point,and open flash point of the product were determined and the structure was characterized by IR,^(1)H NMR and^(13)C NMR.The effects of vacuum conditions,catalyst dosage(percentage of total mass of acid and alcohol,the same as below),and the molar ratio of 2-ethylhexanol to azelaic acid(Hereinafter referred to as molar ratio of alcohol to acid)on the esterification were investigated.The optimum reaction conditions are as follows:vacuum is 0.06 kPa,the catalyst dosage is 0.5%,and the molar ratio of alcohol to acid is 2.8.Compared with the traditional synthesis method,the time required for the acid value to reach the standard is shortened by 92.5%,the time for hydroxyl value is shortened by 89.3%,and the color of the final product is better.