Tribological Properties and Biotoxicity of Gluconate-Based Ionic Liquids as Glycerol Lubricant Additives
Xiaoli Li, Nana Wang, Siyu Liu, Yuchen Sun, Liang Zeng, Jia Li, Chufeng Sun, Meirong Cai, Qiangliang Yu, Feng Zhou
Abstract
With increasing environmental awareness and a growing emphasis on green practices, water-based lubricants have gained significant traction in the lubrication industry. In this study, we incorporated a synthesized environmentally friendly and biodegradable gluconate ionic liquid (ILs), [OMIm][gluconate], into a glycerol. The tribological properties of [OMIm][gluconate] as a water-based lubricant additive were comprehensively investigated. Compared with glycerol, the results of the study showed that the friction coefficient and wear volume of the dispersions were reduced by 38.9% and 97.2%, respectively. In addition, [OMIm][gluconate] has excellent tribological properties, significant antimicrobial properties, and low toxicity to animals. The excellent tribological properties of [OMIm][gluconate] are attributed to the tribologically active element N in the molecular structure of ILs to the surface of the friction pair during the friction process. At the same time, a physicochemical adsorption process occurs at the interface of the additive molecules with the friction pair and a complex tribochemical took place. This process culminates in the formation of a highly durable tribofilm, contributing to the material’s exceptional toughness. Furthermore, the outstanding antimicrobial properties can be attributed to certain lipid-soluble carbon chain structures that disrupt the integrity of bacteria, leading to the effective eradication of Escherichia coli .