Wang Tiantian, Wang Yixin, Wang Xinnan, He Baoluo, Liu Shujuan, Ye Qian, Zhou Feng, Liu Weimin
State Key Laboratory of Solidification Processing, Center of Advanced Lubrication and Seal Materials, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, P. R. China.
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, P. R. China.
ACS Nano. 2024 Dec 10;18(49):33468-33478. doi: 10.1021/acsnano.4c10433. Epub 2024 Nov 25.
Supramolecular Oleogel lubricants provide a versatile and reliable strategy for optimizing the long-term dispersion stability of nanoadditives in the base oils. In this work, GLM-based ionic gelators constructing supramolecular oleogels were prepared by adding ultrasonically treated gallium-based liquid metal (GLM) nanodroplets carrying free radicals and vinyl-containing ionic liquids (ILs) directly to a free radical polymerization system of polymer gelators. The electrostatic interactions between the ionic liquids and GLM nanodroplets enhanced the cross-linking degree of supramolecular gels and formed denser self-assembled structures. The as-prepared GLM-based ionic oleogels as thermoreversible gels exhibit exceptional thixotropic properties. Compared to the base oil PAO10, the coefficient of friction (COF) for both GLM@IGel-1 and GLM@IGel-2 decreased significantly from 0.192 to 0.097, while the wear volume dropped from 100.10 × 10 μm to 13.28 × 10 μm for GLM@IGel-1, and to 9.69 × 10 μm for GLM@IGel-2. In addition, GLM@IGel-2 demonstrates a higher load-bearing capacity of 550 N due to further chemical cross-linking by ionic liquids. The outstanding lubrication performance of GLM-based ionic oleogels is achieved by the synergy of GLM nanodroplets and gel lubricants, promoting the formation of a stable tribo-chemical reaction film.
超分子油凝胶润滑剂为优化纳米添加剂在基础油中的长期分散稳定性提供了一种通用且可靠的策略。在本工作中，通过将携带自由基的超声处理镓基金属液体（GLM）纳米液滴和含乙烯基离子液体（ILs）直接添加到聚合物凝胶剂的自由基聚合体系中，制备了构建超分子油凝胶的基于GLM的离子凝胶剂。离子液体与GLM纳米液滴之间的静电相互作用提高了超分子凝胶的交联度，并形成了更致密的自组装结构。所制备的基于GLM的离子油凝胶作为热可逆凝胶表现出优异的触变性。与基础油PAO10相比，GLM@IGel-1和GLM@IGel-2的摩擦系数（COF）均从0.192显著降低至0.097，而GLM@IGel-1的磨损体积从100.10×10μm降至13.28×10μm，GLM@IGel-2的磨损体积降至9.69×10μm。此外，由于离子液体进一步的化学交联，GLM@IGel-2表现出更高的550 N承载能力。基于GLM的离子油凝胶出色的润滑性能是通过GLM纳米液滴和凝胶润滑剂的协同作用实现的，促进了稳定的摩擦化学反应膜的形成。
