Abstract The excellent physical, mechanical, thermal and electrical properties of carbon nanotubes (CNTs) make them the promising reinforcements for polymer materials. The resulting nanocomposites have been applied in various applications, including but not limited to aerospace components and nanoelectronics. The mechanical performance of CNT reinforced nanocomposites is significantly affected by the interfacial interactions between CNT and polymer matrices. Enhancing the CNT-polymer interface from molecular level, such as chemical functionalization on CNTs, opens new perspectives for improving the mechanical properties of nanocomposites. Although there is a risk that functionalization may destroy the perfect surface of CNTs during fabrication, such chemical treatment can provide desired CNT dispersion state and orientation, resulting in significant improvement in mechanical properties of polymer nanocomposites. In this work, epoxy nanocomposite systems with pristine and functionalized CNTs are modeled respectively. Molecular dynamics simulations are applied to investigate the interfacial characteristics and the mechanical responses of these CNT-polymer nanocomposites. The results reveal that the functionalization can enhance the interfacial shear stress and the Young's modulus of CNT-epoxy nanocomposites. The functional groups not only provide stronger interfacial adhesion with the epoxy matrix, but also act as the sites of mechanical interlocking during deformation. The understanding of the reinforcing mechanism from atomistic level provide physical new insights to material design for advanced nanocomposites.

中文翻译：

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从分子水平了解CNT-环氧树脂纳米复合材料中官能化的影响

摘要 碳纳米管 (CNT) 优异的物理、机械、热学和电学性能使其成为聚合物材料的有前途的增强材料。所得纳米复合材料已应用于各种应用，包括但不限于航空航天部件和纳米电子学。碳纳米管增强纳米复合材料的机械性能受碳纳米管与聚合物基质之间的界面相互作用的显着影响。从分子水平增强碳纳米管-聚合物界面，例如碳纳米管上的化学功能化，为提高纳米复合材料的机械性能开辟了新的前景。尽管功能化可能会在制造过程中破坏 CNT 的完美表面，但这种化学处理可以提供所需的 CNT 分散状态和取向，从而显着提高聚合物纳米复合材料的机械性能。在这项工作中，分别模拟了具有原始和功能化碳纳米管的环氧纳米复合材料系统。分子动力学模拟用于研究这些 CNT-聚合物纳米复合材料的界面特性和机械响应。结果表明，官能化可以提高CNT-环氧树脂纳米复合材料的界面剪切应力和杨氏模量。官能团不仅提供与环氧树脂基质更强的界面粘合，而且在变形过程中充当机械互锁位点。从原子水平理解增强机制为先进纳米复合材料的材料设计提供了新的物理见解。