Chao Song,Ting Hu,Yan Liu,Rong Guo,Jie Han,Juqun Xi,Lei Fan
Conventional industrial conductive lubricants often contain various components to meet their functional requirements for long-term stabilization, lubrication, and conductivity. The complexity of these components makes their preparation, storage, and recycling difficult. To solve this problem, a simple three-component lamellar liquid crystals (LLCs) containing surfactant Brij30, H 2 O, and ionic liquid [C 10 mim]Br was designed and prepared. The results demonstrated that the Brij30/[C 10 mim]Br/H 2 O LLCs system has high stability, lubricity, and conductivity. In the friction test, compared with LLCs without ionic liquids, LLCs with 70 wt% [C 10 mim]Br content showed the best antiwear performance, reducing wear depth by 64.96 % and wear volume by 61.79 %. The lowest coefficient of friction was 0.0877 in the extended cycle test. The conductivity test illustrated the LLCs exhibited high electric conductivity in the [C 10 mim]Br concentration range of 40 wt% to 60 wt%. The addition of ionic liquid not only acts as a co-surfactant in the liquid crystal system to promote the assembly of the surfactant but also improves the lubrication performance and enhances the conductivity of the liquid crystal system. The generation of friction chemically reaction and physically adsorption films formed by LLCs at the friction interface has a synergistic effect on lubrication in the sliding friction process. The spherical wear particles generated by the friction process facilitate rolling friction to promote lubrication. In addition, LLCs can easily realize reusability by removing the wear debris generated by the friction process using the magneto-thermal method. These advantages make the LLCs a promising green, efficient conductive lubricant system.
The lamellar liquid crystal (LLCS) system constructed by surfactant aggregation was demonstrated to exhibit superior tribological properties due to its unique lamellar structure and creep recovery properties. However, the lubrication performance of this kind of liquid crystal system was greatly hindered by its soft nature. Emerging as two-dimensional material, MXene has been promising candidate in tribology on account of its unique layer structure and versatile composition . Taking account of the above fact, herein, nonionic surfactant polyoxyethylene lauryl ether (Brij30), MXene (Ti 3 C 2 T x ), and H 2 O were employed to construct a triple-component composite LLCS system and the related tribological properties were systematically investigated. The results demonstrated that the lubrication performance of the liquid crystal system formed in the presence of Ti 3 C 2 T x was significantly improved compared with that of Brij30/H 2 O LLCS. The average friction coefficient of the composite LLCS system was in the range of 0.1155–0.1266, and the best lubrication performance was achieved when the Ti 3 C 2 T x content was kept as 6 mg/mL. MXene is also able to achieve good dispersion in liquid crystal systems. The enhanced lubrication performance of the composite LLCS system was mainly due to the synergistic effect of MXene nanosheets and LLCS. In addition, the iron oxides generated by the reaction during the friction process also promote lubrication. It is believed that the current work provides an alternative method for the development of MXene/LLCS-lubricating materials.
危险品化学品经营许可证（带存储）