The synthesis of propylene glycol monoester, using coconut oil and 1,2- propanediol as raw materials via alcoholysis in solvent - free system was studied, and the reaction products were analyzed by HPLC - RID. Compared with other eleven kinds of common commercial lipases, the immobilized Jipase Novozyme 435 from Candida antarctic had the best effect. The effects of enzyme dosage, substrate molar ratio, reaction temperature and water dosage on the alcoholysis reaction were investigated. The reaction conditions were optimized as follows; molar ratio of 1 ,2 -propanediol to coconut oil 8 : 1, reaction temperature 50 ℃ , enzyme dosage 300 U/g(based on the mass of substrate) , water dosage 1. 0% (based on the mass of 1,2 - propanediol). After reaction for 6 h under the optimal conditions, the content of propylene glycol monoester was 53.48% .%在无溶剂体系中,对脂肪酶催化椰子油与1,2-丙二醇醇解反应合成椰子油基丙二醇单酯进行了研究,采用HPLC-RID对目标产物进行分析.比较了12种常用商品化脂肪酶,结果表明固定化脂肪酶Novozyme 435合成椰子油基丙二醇单酯的效果最好.以Novozyme 435为催化剂,进一步研究了酶加量、底物摩尔比、反应温度和水加量对醇解反应的影响.确定最优的反应条件为:1,2-丙二醇与椰子油摩尔比8∶1,反应温度50℃,水加量1.0％(以1,2-丙二醇质量计),酶加量300U/g(以底物质量计).在最优反应条件下,醇解反应6h,椰子油基丙二醇单酯生成量达到53.48％.
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