合成酯类基础油三羟甲基丙烷油酸酯(TMPTO)具有优异的润滑性能和多种优异特质,广泛应用于环保液压油、发动机油等抗燃液压油中。为提高TMPTO在复杂工况下的润滑性能,并实现添加工艺简便、成本低廉、合成方法绿色,本研究利用酯化反应合...合成酯类基础油三羟甲基丙烷油酸酯(TMPTO)具有优异的润滑性能和多种优异特质,广泛应用于环保液压油、发动机油等抗燃液压油中。为提高TMPTO在复杂工况下的润滑性能,并实现添加工艺简便、成本低廉、合成方法绿色,本研究利用酯化反应合成了两种常用的润滑油添加剂1,6-己二异氰酸酯(HDI)和丙烯酸-2-羟乙酯(HEA)的半封端产物(HDI-HEA),通过化学接枝在石墨烯及其衍生物的表面,制备出了多种功能化改性石墨烯添加剂,其中功能化改性石墨烯(G-HDI-HEA)可作为TMPTO的最佳润滑油添加剂。通过FTIR、XRD、SEM、TEM、Raman、XPS等表征分析证实HDI-HEA成功接枝到石墨烯表面。为了验证不同G-HDI-HEA含量的改良基础润滑油(G-HDI-HEA/TMPTO)的润滑性能,通过四球摩擦试验机测试磨斑直径、摩擦系数确定G-HDI-HEA对TMPTO摩擦性能的影响。结果表明:先合成HDI-HEA后接枝石墨烯的方法可以避免HDI上两个NCO同时连接一个或多个石墨烯,提高石墨烯的扩散性能的同时也减少了石墨烯的团聚。由于采用的一锅串联法无需催化剂,可以减少大量成本和复杂的后处理。当G-HDI-HEA的含量为0.01%时,G-HDI-HEA/TMPTO的磨斑直径减小约27%,最大润滑系数降低10%。Synthetic ester base oil trimethylolpropane oleate (TMPTO) has excellent lubrication performance and various outstanding characteristics, and is widely used in environmentally friendly hydraulic oils, engine oils, and other fire-resistant hydraulic oils. To improve the lubrication performance of TMPTO base oil under complex working conditions, and to achieve simple addition process, low cost, and green synthesis method. This work utilized a catalyst free esterification reaction to connect two commonly used lubricant additives, 1,6-hexanedioic acid (HDI) and 2-hydroxyethyl acrylate (HEA), into a half sealed end product (HDI-HEA), which was grafted onto the surface of graphene and its derivatives to prepare various functionalized modified graphene additives. Among them, functionalized modified graphene (G-HDI-HEA) can be used as the best lubricant additive for TMPTO base oil. Characterization techniques such as FTIR, XRD, SEM, TEM, Raman, and XPS confirmed the successful grafting of HDI-HEA onto the graphene surface. To evaluate the lubricating performance of the modified base oil (G-HDI-HEA/TMPTO) with varying G-HDI-HEA content, a four-ball friction tester was used to measure the wear scar diameter and friction coefficient, determining the impact of G-HDI-HEA on the frictional properties of TMPTO. The results showed that the method of first synthesizing HDI-HEA and then grafting it onto graphene prevents the two NCOs of HDI from simultaneously bonding to one or multiple graphene sheets, thereby improving graphene dispersion while reducing agglomeration. Additionally, the one-pot tandem method employed requires no catalyst, significantly reducing costs and complex post-processing. When the G-HDI-HEA content was 0.01%, the wear scar diameter of G-HDI-HEA/TMPTO decreased by approximately 27%, and the maximum friction coefficient was reduced by 10%.展开更多
文摘合成酯类基础油三羟甲基丙烷油酸酯(TMPTO)具有优异的润滑性能和多种优异特质,广泛应用于环保液压油、发动机油等抗燃液压油中。为提高TMPTO在复杂工况下的润滑性能,并实现添加工艺简便、成本低廉、合成方法绿色,本研究利用酯化反应合成了两种常用的润滑油添加剂1,6-己二异氰酸酯(HDI)和丙烯酸-2-羟乙酯(HEA)的半封端产物(HDI-HEA),通过化学接枝在石墨烯及其衍生物的表面,制备出了多种功能化改性石墨烯添加剂,其中功能化改性石墨烯(G-HDI-HEA)可作为TMPTO的最佳润滑油添加剂。通过FTIR、XRD、SEM、TEM、Raman、XPS等表征分析证实HDI-HEA成功接枝到石墨烯表面。为了验证不同G-HDI-HEA含量的改良基础润滑油(G-HDI-HEA/TMPTO)的润滑性能,通过四球摩擦试验机测试磨斑直径、摩擦系数确定G-HDI-HEA对TMPTO摩擦性能的影响。结果表明:先合成HDI-HEA后接枝石墨烯的方法可以避免HDI上两个NCO同时连接一个或多个石墨烯,提高石墨烯的扩散性能的同时也减少了石墨烯的团聚。由于采用的一锅串联法无需催化剂,可以减少大量成本和复杂的后处理。当G-HDI-HEA的含量为0.01%时,G-HDI-HEA/TMPTO的磨斑直径减小约27%,最大润滑系数降低10%。Synthetic ester base oil trimethylolpropane oleate (TMPTO) has excellent lubrication performance and various outstanding characteristics, and is widely used in environmentally friendly hydraulic oils, engine oils, and other fire-resistant hydraulic oils. To improve the lubrication performance of TMPTO base oil under complex working conditions, and to achieve simple addition process, low cost, and green synthesis method. This work utilized a catalyst free esterification reaction to connect two commonly used lubricant additives, 1,6-hexanedioic acid (HDI) and 2-hydroxyethyl acrylate (HEA), into a half sealed end product (HDI-HEA), which was grafted onto the surface of graphene and its derivatives to prepare various functionalized modified graphene additives. Among them, functionalized modified graphene (G-HDI-HEA) can be used as the best lubricant additive for TMPTO base oil. Characterization techniques such as FTIR, XRD, SEM, TEM, Raman, and XPS confirmed the successful grafting of HDI-HEA onto the graphene surface. To evaluate the lubricating performance of the modified base oil (G-HDI-HEA/TMPTO) with varying G-HDI-HEA content, a four-ball friction tester was used to measure the wear scar diameter and friction coefficient, determining the impact of G-HDI-HEA on the frictional properties of TMPTO. The results showed that the method of first synthesizing HDI-HEA and then grafting it onto graphene prevents the two NCOs of HDI from simultaneously bonding to one or multiple graphene sheets, thereby improving graphene dispersion while reducing agglomeration. Additionally, the one-pot tandem method employed requires no catalyst, significantly reducing costs and complex post-processing. When the G-HDI-HEA content was 0.01%, the wear scar diameter of G-HDI-HEA/TMPTO decreased by approximately 27%, and the maximum friction coefficient was reduced by 10%.
