Abstract In the present work, three kinds of halogen-free ionic liquids (ILs) incorporating long-chain quaternary phosphonium as cations and dioctylsulfosuccinate (DOSS) as the anion were synthesized and characterized and the tribological properties of phosphonium ionic liquids were investigated as neat lubricants for steel ball–steel disc friction pairs at room temperature (RT) and elevated temperature (100 °C). The ILs were found to be noncorrosive and highly thermally stable and showed better antiwear and friction reduction performance than commercially available synthetic lube base oil poly-α-olefin (PAO10) and conventionally used IL 1-methyl-3-hexylimidazolium hexafluorophosphate (L-P106). Scanning electron microscopy (SEM) and energy-dispersive spectroscopic (EDS) analysis of the worn-out surfaces of the steel discs was performed and the results revealed that physical adsorption and tribochemical reactions occurred and formed a protective boundary film on the worn steel surface to prevent direct steel–steel contact between rubbing surfaces.

中文翻译：

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用于润滑应用的无卤磷基离子液体的合成与研究

摘要 在目前的工作中，合成并表征了三种以长链季鏻为阳离子和二辛基磺基琥珀酸酯 (DOSS) 为阴离子的无卤离子液体 (ILs) 作为纯润滑剂的摩擦学性能。适用于室温 (RT) 和高温 (100 °C) 下的钢球-钢盘摩擦副。与市售合成润滑油基础油聚α-烯烃 (PAO10) 和常规使用的 IL 1-甲基-3-己基咪唑鎓六氟磷酸酯 (L-P106) 相比，发现这些 IL 无腐蚀性和高度热稳定性，并显示出更好的抗磨损和减摩性能。 ）。