Page 27 - 摩擦学学报2025年第4期

第 4 期 孙学敏, 等: 环境友好型氨基酸基离子液体作为水润滑添加剂的摩擦学机制研究 515

3. State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics,
Chinese Academy of Sciences, Gansu Lanzhou 730000, China)
Abstract: The utilization of water-based lubricants in certain applied fields, as an alternative to oil-based lubricants that
are prone to causing environmental pollution, represents one of the effective strategies for achieving green tribology. To
tackle the issues of subpar lubrication properties and susceptibility to corrosion of friction interface for water-based
lubrication, two amino acids-based ionic liquids, Lys-LS and Arg-LS, were synthesized in this manuscript by a simple
proton exchange reaction using L-lysine or L-arginine and Lauroyl sarcosine, and were utilized as water-based lubricant
additives. The thermal decomposition 5% temperatures of Lys-LS and Arg-LS reached 219.8 ℃ and 217.5 ℃,
respectively, exhibiting exceptional thermal stability. The corrosion resistance properties of Lys-LS and Arg-LS aqueous
solutions against first-grade gray cast iron sheets were assessed in accordance with the methodologies outlined in the
national standard GB 6 144-2010. Both the corrosion area and the number of corrosion stains were significantly reduced
compared to deionized water when the two amino acids-based ionic liquids were incorporated at a mass fraction of ≥
0.5%. The tribological properties of Lys-LS and Arg-LS additives were investigated using an SRV-V fretting friction
and wear tester and automatic true-color confocal microscope. Compared with deionized water, the friction coefficient
and wear volume of the water-based lubricants were reduced by about 70% and 85%, respectively, when Lys-LS and
Arg-LS were supplemented at a concentration of 0.5%, providing a significant friction reduction and anti-wear
performance. The micro-morphological analysis results of the wear spot surface revealed that the wear surface was
smoother after lubricated by the aqueous solution containing ionic liquids additives, and at the same time, the adhesive
wear and corrosive wear were effectively suppressed. The lubrication mechanisms of two ionic liquids additives were
investigated in depth using the quartz crystal microbalance (QCM) and the X-ray photoelectron spectroscopy (XPS). The
QCM tests indicated that the two amino acid-based ionic liquids could be effectively adsorbed onto the rubbing interface
during the friction process to form a stable adsorption films. The XPS analysis results revealed that the tribochemical
reaction occurred between the two additives and the surface of the friction pair, and a tribological protective films
enriched with C, Fe, O and N elements were generated. The tribochemical reaction films and physical/chemical
adsorption films formed by the ionic liquids at the interface worked synergistically to effectively prevent direct contact
between the sliding pairs, endowing the water-based lubricant with excellent tribological properties. The two amino
acids-based ionic liquids additives were characterized by simple preparation, non-toxicity and greenness, and were
promising to be employed as critical additives for metalworking fluids and flame-retardant hydraulic fluids.
Key words: amino acid-based ionic liquids; water-based lubricants; tribological properties; lubrication mechanism; eco-
friendly additives

摩擦磨损会导致机械零件的损坏和资源的浪费， 离子液体是1种完全由阴阳离子构成的室温熔融
[9]
在大多数工业化国家，这些损失总计约占国民生产总 盐 ，具有低挥发性、不可燃、蒸汽压低、热稳定性高
[1-2] [10-16]
值的5%~7% . 合理的使用润滑液是减少摩擦磨损最 和表面吸附性能强等优点 . 自2001年离子液体首
有效的方式之一. 润滑油因其优异的摩擦学性能，在 次作为润滑剂应用于摩擦学领域以来 ，得到了广泛
[17]
工业各个领域得到了广泛的应用. 但润滑油存在导热 的关注. 将离子液体作为润滑添加剂使用既可保留其
[18]
系数小和易燃易爆等缺点 [3-4] ，限制了其在煤矿、金属 优异的摩擦学特性 ，又可以节约成本. 早期对于离
[19]
加工和液压传动等领域的应用. 此外，油基润滑液还 子液体添加剂的研究，多数集中于水-甘油溶液 和
[5]
[20]
存在着生物降解性差、污染环境等弊端 . 因此，寻找 水-乙二醇 2种体系中，且多数含有杂原子 [21-22] 和卤素 [23]
资源节约和环境友好型的绿色润滑介质逐渐成为科 等，水解稳定性较差，在摩擦过程中容易对摩擦副产
[6]
学家关注的重点 . 生腐蚀，同时对环境具有一定的污染. 近年来，人们对
水基润滑液具有冷却性能优异、难燃、导热系数 于离子液体添加剂的研究重点偏向于含氨基酸及其
[24]
高、来源广泛和易降解等优点 ，被广泛用作金属加 衍生物的绿色离子液体. Zheng等 利用N-油酰肌氨
[7]
工液和难燃液压液. 然而，水基润滑普遍存在着润滑 酸与甲基乙醇胺原位合成了离子液体[osar][mea]，研
性不足和抗腐蚀性能差等问题，严重制约了水基润滑 究其在水-甘油中的摩擦学性能，证明了[osar][mea]可
[8]
体系的发展与应用 . 合理的使用添加剂能显著提高 显著提升水-甘油的抗腐蚀能力，同时具有优异的摩
[25]
水的物理化学性能和润滑性能. 擦学性能. Yang等 合成了7种氨基酸-四丁基磷离子