Abstract Novel lubricant oil-loaded multilayer composite microcapsules with poly(urea-formaldehyde) (PUF) shells assembled with polydopamine-functionalized oxidized carbon nanotubes (CNTs-o-PDA) are fabricated. Results indicate that the PUF microcapsules show spherical shape structure with a mean diameter of 110 μm and an encapsulation capacity of 83.5%. CNTs are successfully assembled on the surface of lubricant oil-containing PUF microcapsules (LPMs). Thermal stability tests reveal the initial decomposition temperature of microcapsules elevated by 75 °C. Furthermore, the microcapsules are embedded into epoxy to prepare self-lubricating composites. The coefficient friction and wear rate of self-lubricating composites incorporating 20 wt% CNTs-o-PDA assembled LPMs are 33.79% and 74.28% lower than that of composites incorporating LPMs, and which are 64.07% and 99.54% lower than that of the pure epoxy resin, respectively. Further studies confirm that the interface bonding strength between epoxy and microcapsules is effectively improved by the introduction of CNTs-o-PDA on the surface of PUF microcapsules. The synergistic effect between microcapsules containing lubricant oil and CNT layer played an important role in improving the tribological properties of polymer composites.

中文翻译：

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新型多层复合微胶囊的合成及其在自润滑聚合物复合材料中的应用

摘要 制备了新型负载润滑油的多层复合微胶囊，其聚脲甲醛 (PUF) 壳与聚多巴胺功能化的氧化碳纳米管 (CNTs-o-PDA) 组装在一起。结果表明，PUF微胶囊呈球形结构，平均直径为110 μm，包封率为83.5%。碳纳米管成功地组装在含润滑油的 PUF 微胶囊 (LPM) 的表面上。热稳定性测试表明微胶囊的初始分解温度提高了 75 °C。此外，将微胶囊嵌入环氧树脂中以制备自润滑复合材料。包含20 wt% CNTs-o-PDA组装LPMs的自润滑复合材料的摩擦系数和磨损率比包含LPMs的复合材料低33.79%和74.28%，分别比纯环氧树脂低64.07%和99.54%。进一步的研究证实，在PUF微胶囊表面引入CNTs-o-PDA可有效提高环氧树脂与微胶囊之间的界面结合强度。含润滑油的微胶囊与碳纳米管层之间的协同作用在提高聚合物复合材料的摩擦学性能方面发挥了重要作用。