Mechano-assisted ionic liquid-modified MXene enhances tribological properties of waterborne epoxy coatings

Two-dimensional MXene nanosheets have attracted considerable attention as lubricating fillers in polymer coatings owing to their excellent interlayer sliding and high tribofilm-forming capabilities. However, their aggregation within the polymer matrix and weak interfacial interactions hinder their ability to achieve high wear resistance. Existing modification strategies for MXenes (such as silane coupling or catechol-based modifications) frequently involve complex processes, toxic reagents, and/or specific chemical reaction environments, and the direct surface modification of MXene using lubricating agents for synergistic lubrication remains underexplored. Herein, we propose a mechano-assisted surface modification strategy to synthesize ionic liquid-functionalized MXene (MX-IL) using 1-aminopropyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, a water-soluble ionic liquid (IL). The IL anchors to MXene nanosheets via Ti–N coordination bonds and electrostatic interactions, whereas its highly polar anions/cations and –NH 2 groups enhance the dispersibility and interfacial compatibility of MXene with waterborne epoxy resin, improving the storage modulus, adhesion strength, and hardness. This dual-action mechanism, involving the combination of the inherent weak interlayer shear strength of MXene with the strong adsorption effect of IL, considerably improves the tribological properties of nanocomposite coatings. Tribological tests reveal that incorporating 1.0 wt% MX-IL decreases the friction coefficient and wear rate of pure epoxy coating by 39.8 % and 84.5 %, respectively. The mechano-assisted IL modification eliminates the need for toxic reagents and intricate synthesis steps, offering a simple, ecofriendly approach for fabricating high-performance, self-lubricating polymer coatings. This study addresses critical challenges in MXene–polymer composite design and provides a foundational framework for the development of advanced lubrication materials via synergistic surface engineering.