Three α-alkene lubricants, differentiated by chain length, were selected as model compounds to investigate the influence of chain length on tribological properties. The novelty of this study lies in setting chain length as the sole variable to explore its impact on surface and adsorption energy. Based on the above findings, the study provides a unique explanation of the intrinsic relationship between chain length and tribological performance. The tribological properties of the three α-alkenes were compared, and subsequent characterization methods elucidated the wear mechanisms and explored tribochemical reactions. The study employed the Owens–Wendt–Rabel–Kaelble (OWRK) method and density functional theory (DFT) to investigate each compound’s surface energy and adsorption energy. Experimental results revealed that the average friction coefficients (abridged as COF) for 1-decene, 1-tetradecene, and 1-octadecene decreased sequentially to 0.125, 0.099, and 0.075, respectively. The wear volume of 1-tetradecene decreased by 53.2% and that of 1-octadecene decreased by 64.0% compared to 1-decene. This can be attributed to the simultaneous enhancement of the surface energy and adsorption energy with increasing chain length. On the one hand, the increase in surface energy facilitates tribochemical reactions positively influencing the formation of tribofilms. On the other hand, the increase in adsorption energy enhances the adsorption of lubricants on the substrate surface. The synergy of these two effects allows 1-octadecene and 1-tetradecene (long-chain α-alkenes) to exhibit superior tribological performance compared to that of 1-decene (short-chain α-alkenes). Ultimately, this study offers unique insights into understanding lubrication mechanisms.

中文翻译：

---

不同链长 α-烯烃分子的摩擦学机制与界面行为的视角


选择三种以链长区分的 α-烯烃润滑剂作为模型化合物，研究链长对摩擦学特性的影响。这项研究的新颖之处在于将链长作为唯一变量来探索其对表面和吸附能的影响。基于上述发现，该研究为链长与摩擦学性能之间的内在关系提供了独特的解释。比较了三种 α-烯烃的摩擦学特性，随后的表征方法阐明了磨损机制并探索了摩擦化学反应。该研究采用 Owens-Wendt-Rabel-Kaelble （OWRK） 方法和密度泛函理论 （DFT） 来研究每种化合物的表面能和吸附能。实验结果表明，1-癸烯、1-十四烯和 1-十八烯的平均摩擦系数（缩写为 COF）依次下降至 0.125、0.099 和 0.075。与 1-癸烯相比，1-十四烯的磨损体积减少了 53.2%，1-十八烯的磨损体积减少了 64.0%。这可以归因于随着链长的增加，表面能和吸附能同时增强。一方面，表面能的增加促进了摩擦化学反应，对摩擦膜的形成产生了积极影响。另一方面，吸附能的增加增强了润滑剂对基材表面的吸附。这两种效应的协同作用使 1-十八烯和 1-十四烯（长链 α-烯烃）与 1-癸烯（短链 α-烯烃）相比表现出卓越的摩擦学性能。最终，这项研究为理解润滑机制提供了独特的见解。