功能化离子液体润滑剂的合成及其润滑性能研究

通过两步法合成了含酯基官能团的功能化离子液体1-乙酸乙酯基-3-甲基咪唑四氟硼酸盐(EAMIM]BF4),用核磁共振和红外光谱对其进行了结构表征;对其作为润滑剂的物化性质进行了测定,并选择了含有相同烷基的传统离子液体1-丁基-3-甲基咪唑四氟硼酸盐(BMIM]BF4)进行对比;在四球机上评定两种离子液体的承载能力,在SRV摩擦磨损试验机上评价了两种离子液体的润滑性能,并选择低蒸气压的含氟润滑剂全氟聚醚(PFPE)作为对比。结果表明:在常温下,两种离子液体较PFPE具有更高的承载能力和更好的润滑性能;两种离子液体相比,EAMIM]BF4由于粘度较大其在低载荷下减摩性较BMIM]BF4稍差,但其抗磨性始终优于BMIM]BF4。

Study on the Synthesis and Lubricity of a Functionalized Ionic Liquid as a Lubricant

A new kind of ester-group functionalized ionic liquid, 1-ethoxycarbonylmethyl-3-methyl imidazolium tetrafluoroborate （EAMIM]BF4）, was synthesized through a typical two-step way and the product was characterized by 1HNMR and FT-IR analysis.The physicochemical properties of the functionalized ionic liquid as a lubricant were studied and compared with a traditional ionic liquid, 1-butyl-3-methyl imidazolium tetrafluoroborate （BMIM]BF4）, which had the same alkyl as the functionalized one. The load-carrying capacities of these two ionic liquids were evaluated on the four-ball machine. The lubricities of them were studied on an SRV friction and wear tester and compared with the perfluoroalkylpolyether （PFPE）, a low-volatility and fluorine containing lubricant. Results showed that the two ionic liquids are superior to PFPE in terms of load-carrying capacity and lubricity at normal temperature. EAMIM]BF4 shows worse friction-reducing ability at relatively low loads owing to its higher viscosity but it always exhibits better anti-wear ability than BMIM]BF4.