合成了几种三丁基烷基四氟硼酸季膦盐离子液体,用核磁共振氢谱仪表征其结构,用差热分析仪测定其热稳定性,在SRV摩擦磨损试验机上评价其作为润滑剂对钢/锡青铜摩擦副的摩擦磨损性能,并与磷嗪X-1P和2-乙基-3-已基眯唑四氟硼酸盐(L-P206)进行比较,采用X射线光电子能谱仪和扫描电子显微镜分析磨损表面元素的化学状态及其磨斑形貌.结果表明,三丁基烷基四氟硼酸季膦盐离子液体的热稳定性和抗氧化性能较好,作为钢/锡青铜摩擦副润滑剂具有优异的摩擦磨损性能,摩擦系数极低(〈0.05),抗磨性优于常规二烷基咪唑基离子液体.
Some ionic liquids of tributylalkyl phosphonium tetrafluoroborate were prepared and characterized by 1H-NMR. Thermal stability was characterized by thermogravimetric analysis (TGA). Tribological properties of these phosphonium ionic liquids as a new kind of promising lubricant for a steel/Cu-Sn alloy contact, were investigated with an Optimal SRV friction and wear tester. As a comparison, phosphazene X-1P and L-P206, were also tested at the same conditions. Elemental composition and chemical nature of the boundary films generated on the worn surface were analyzed with a Kevex energy dispersive X-ray analyzer equipped on a scanning electron microscope, and an X-ray photoelectron spectroscope. As a result, the synthetic ionic liquids showed better friction-reduction and antiwear behavior than the L-P206 did. For applied load ranging from 100 N to 300 N, TPTB exhibited only 1/2 friction coefficient and 1/a wear volume in comparison with L-P206.