面向深地工程装备中关键橡胶密封材料在高温磨粒环境下易发生磨损失效的问题，亟需提升其摩擦学性能与服役可靠性。为此，提出一种协同改性策略：通过PEI/CA对芳纶纤维进行表面改性以增强界面结合能力，并引入PDA修饰TiO₂微胶囊实现界面润滑调控。系统研究了填料含量(5 wt%、10 wt%、15 wt%)及微胶囊与改性纤维配比(1:1-1:3)对复合材料摩擦性能的影响。结果表明，当填料含量为10 wt%、微胶囊与改性纤维质量比为1:3时，复合材料表现出最低摩擦系数（0.3），降低约25%。进一步考察最优体系在SiO₂磨粒参与及50℃、80℃热老化条件下的摩擦磨损行为,并以仅添加10 wt%原始芳纶纤维的复合材料为对照。结果表明，相较于单一纤维增强体系，双改性复合材料具有更低的摩擦系数和更优的磨损稳定性，其性能提升归因于界面结合增强与稳定润滑膜的协同作用。创新性地构建了基于PEI/CA界面改性与PDA微胶囊润滑调控的双功能协同体系，并揭示其在复杂工况下的减摩耐磨机制。为恶劣服役环境下高性能橡胶密封材料的设计提供了新的思路。
To address the wear failure of rubber sealing materials used in deep underground engineering equipment under high-temperature abrasive conditions, improving their tribological performance and service reliability is essential. In this study, a synergistic modification strategy was proposed, in which aramid fibers were modified with polyethyleneimine/citric acid (PEI/CA) coating to strengthen interfacial bonding, while polydopamine (PDA)-modified TiO₂ microcapsules were incorporated to facilitate interfacial lubrication. The effects of filler content (5 wt%, 10 wt%, and 15 wt%) and the mass ratio of microcapsules to modified fibers (1:1 to 1:3) on the tribological performance of the composites were systematically investigated. The results indicated that when the total filler content was 10 wt% and the mass ratio was 1:3, the composite exhibited the lowest friction coefficient (0.3), corresponding to a reduction of approximately 25%. Furthermore, the tribological behaviors of the optimal system were evaluated under SiO₂ abrasive conditions and thermal aging at 50℃ and 80℃, using a composite containing only 10 wt% pristine aramid fibers as a control. The results indicate that the dual-modified composite exhibits lower friction coefficients and superior wear stability compared with the single fiber-reinforced system, which is attributed to the synergistic effect of enhanced interfacial bonding and the formation of a stable lubricating film. A dual-functional synergistic system based on PEI/CA interfacial modification and PDA-assisted microcapsule lubrication is established, providing a new strategy for designing high-performance rubber sealing materials under harsh service conditions.
 

丁腈橡胶、芳纶纤维、TiO2微胶囊、摩擦学性能、磨粒磨损