TRIBOLOGICAL APPLICATIONS OF PROTIC IONIC LIQUIDS: EFFECTS OF IONIC STRUCTURE, CHALLENGES, AND FUTURE PERSPECTIVES
DOI:
https://doi.org/10.11113/jtse.v13.257Keywords:
Protic ionic liquids (PILs), lubrication, ion moiety, solubility, hydrolytic stabilityAbstract
Protic ionic liquids (PILs) have emerged as promising candidates for advanced lubrication owing to their intrinsic thermal stability, negligible volatility, and ability to form protective boundary layers at sliding inter faces. This review revealed ionic species present with long alkyl group, or specialised functional group that enhanced intermolecular interaction which tend to improves tribological ability, thermal stability and raise viscosity. Additionally, the compatibility of PIL with base oils is critical for effective additive performance, as insufficient miscibility limits ion transport and interfacial coverage. Hydrolytic stability is another critical concern for application in high-moisture environment which are rarely examined in literature. Collectively, the current findings highlight the need for integrated molecular design strategies that simultaneously consider chain length, ion-pair chemistry, oil compatibility and hydrolytic stability, to realize the full potential of PILs as tunable, high-performance lubricants or additives.
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