Effect of hydroxyl functionalized ionic liquid additives on rheological and tribological properties of titanium complex grease

• Published in: Tribology international Vol. 193; p. 109416
• Main Authors: Liu, Ningbo, Che, Qinglun, Li, Yi, Hu, Litian, Zhang, Jianjun, Zhang, Songwei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2024
• Subjects: Hydroxyl functionalized ionic liquids; Rheology property; Titanium complex grease; Tribology; Rheology property; Titanium complex grease; Hydroxyl functionalized ionic liquids; Tribology
• ISSN: 0301-679X
• DOI: 10.1016/j.triboint.2024.109416

In this work, two kinds of hydroxyl functionalized ionic liquids (ILs) 1-butyl-3-methylimidazole salicylate [BMIM][SA] and 1-butyl-3-methylimidazole caffeate [BMIM][CA] were synthesized as additives for titanium complex grease (TCG). Two ILs can effectively improve the physicochemical properties of TCG. Among them, [BMIM][CA] significantly improves the yield stress of TCG and improved its ability to resist deformation. Tribological tests showed that both ILs improved the friction reduction and antiwear properties. And [BMIM][CA] containing two adjacent phenolic hydroxyl group performed the best. This may be because it can effectively participate in tribochemical reactions, forming a large number of organic tribochemical products, which play a key role in promoting lubrication. •Two hydroxyl functionalized ILs were synthesized and used as additives in TCG.•Both ILs can form a new interaction with the thickener molecules.•[BMIM][CA] could enhance the yield stress of TCG base grease.•Both ILs can improve the lubrication performance of TCG.•[BMIM][CA] can coordinate with the steel surface to form a stable lubricating film.