Zhang Zhenyu, Du Yuefeng, Zhu Chunhua, Guo Liangchao, Lu Yao, Yu Jinhong, Parkin Ivan P, Zhao Junhua, Guo Dongming
Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China.
Institute of Mechanics and Advanced Materials, School of Mechanical Engineering, Jiangnan University, Wuxi 214122, China.
Nanoscale. 2021 Feb 11;13(5):2855-2867. doi: 10.1039/d0nr08600b.
Epoxy resins (ERs) have extraordinary mechanical, electrical and chemical properties, and are widely used in the aerospace, electronics and marine industries. Nonetheless, solidified ERs have intrinsic brittleness and low wear resistance. Until now, the promotion of the wear resistance of ER is limited to 30 times, through blending from one to four reinforcing materials. Therefore, it has been a challenge to enhance the wear resistance of ER to over 30 times. Additionally, mechanisms to improve the tribological properties of polymer composites are elusive. In this study, novel ER/graphene composites (ECs) were developed, and the wear resistance of EC with 5 wt% graphene (EC5) was shown to be 628 times that of pure ER at 10 N. To the best of our knowledge, the unprecedented enhancement of wear resistance for ER is the highest reported. The enhancement mechanisms of graphene reinforcement to ER were determined by molecular dynamics simulations. When the content of graphene reaches 5 wt%, exfoliated graphene flakes adhere the most on the surface of a stainless-steel ball during sliding tests, reducing the wear most effectively. However, when the content of graphene is over 5 wt%, graphene flakes accumulate inside the composites, and less exfoliated graphene flakes adhere to the surface of the ball during sliding, increasing the wear. The developed binary ECs are light-weight and cost-effective and have minimal impact on the environment. This composite has many potential applications for high-performance components used in the aerospace, electronics and marine industries.
环氧树脂（ERs）具有优异的机械、电气和化学性能，广泛应用于航空航天、电子和海洋工业。然而，固化后的环氧树脂具有固有的脆性和低耐磨性。到目前为止，通过添加一到四种增强材料进行共混，环氧树脂耐磨性的提升仅限于30倍。因此，将环氧树脂的耐磨性提高到30倍以上一直是一个挑战。此外，改善聚合物复合材料摩擦学性能的机制尚不清楚。在本研究中，开发了新型的环氧树脂/石墨烯复合材料（ECs），结果表明，含5 wt%石墨烯的复合材料（EC5）在10 N载荷下的耐磨性是纯环氧树脂的628倍。据我们所知，环氧树脂耐磨性前所未有的提高是目前报道的最高水平。通过分子动力学模拟确定了石墨烯增强环氧树脂的增强机制。当石墨烯含量达到5 wt%时，在滑动测试中，剥离的石墨烯薄片在不锈钢球表面的附着最多，最有效地减少了磨损。然而，当石墨烯含量超过5 wt%时，石墨烯薄片在复合材料内部堆积，在滑动过程中附着在球表面的剥离石墨烯薄片减少，从而增加了磨损。所开发的二元复合材料重量轻、成本低，对环境影响最小。这种复合材料在航空航天、电子和海洋工业中用于高性能部件方面有许多潜在应用。
