通过季铵化法合成一系列咪唑类离子液体并附着在表面硅烷化的Fe₃O₄磁性纳米颗粒上,用于催化季戊四醇/三羟甲基丙烷与油酸的酯化反应制备季戊四醇油酸酯和三羟甲基丙烷油酸酯。FT-IR、BET、XRD、VSM等表征结果表明成功制备了磁性聚合离子液体。确定了合成季戊四醇油酸酯的最佳反应条件为:催化剂质量分数5%、酸醇摩尔比4:1、反应温度190℃、反应时间7 h,此时磁性聚合离子液体酯化率达到94.43%;合成三羟甲基丙烷油酸酯的最佳反应条件为:催化剂质量分数5%、酸醇摩尔比3.5:1、反应温度150℃、反应时间7 h,此时磁性聚合离子液体酯化率达到97.60%。在2种不同的酯化反应体系中,磁性聚合离子液体在重复使用多次后依旧保持较高的酯化率。同时对磁性聚合离子液体的2种酯化反应的催化动力学进行了研究,得出活化能Ea₁=26.27 kJ/mol、Ea₂=20.38 kJ/mol。

A series of imidazole-based ionic liquids are synthesized through quaternization method,attached to the surface-silanized Fe₃O₄ magnetic nanoparticles,and used to catalyze the esterification reaction of pentaerythritol/trimethylolpropane with oleic acid to prepare pentaerythritol oleate.By using FT-IR,BET,XRD,VSM and other characterization techniques,it is proved that magnetic polymeric ionic liquids are successfully prepared.A 5% of catalyst dosage,a 4:1 of molar ratio between oleic acid and pentaerythritol,a reaction temperature at 190℃,and 7 h of reaction time are determined as the optimal reaction conditions for the synthesis of pentaerythritol oleate.Under these conditions,the esterification rate over magnetic polymeric ionic liquid reaches 94.43%.The optimal reaction conditions for the synthesis of trimethylolpropane oleate are as follows:the catalyst dosage is 5wt.%,the molar ratio of oleic acid to trimethylolpropane is 3.5:1,the reaction temperature is at 150℃,and the reaction lasts for 7 h.Under these conditions,the esterification rate over magnetic polymeric ionic liquid reaches 97.60%.In these two different esterification reaction systems,the magnetic polymeric ionic liquid still maintains a high esterification rate after repeated uses for many times.The catalytic kinetics of magnetic polymeric ionic liquids in two esterification reactions are studied and it is found that the activation energies are 26.27 kJ·mol^-1 and 20.38 kJ·mol^-1,respectively.