Molecular dynamics (MD) simulations were carried out to explore the ideal structure design of graphene oxide (GO) modified by poly(dopamine) (PDA) which is more conducive to performances improvement of epoxy resin composites. The epoxy resin matrix was compounded with PDA-modified GO (PDA-GO) particles with different structures including the surface modification and the interlayer inserted modification. The interaction energy (E_inter), molecular mobility (MSD), packing density (RDF), thermal and mechanical properties of different structure of PDA-GO/epoxy composites were calculated. Interestingly, it was found that the increased layer number of GO weakened the interfacial binding between GO particles and the epoxy matrix, and prevented the compact stacking of epoxy molecular chains, but the PDA-GO with inserted-modification structure displayed a desirable interfacial binding with epoxy resin and dramatically improved thermal and mechanical performances of the resulting composites. In addition, the surface-modification of single layer GO using PDA had negative effects on micro and macro performances of epoxy matrix composites. This work provided special revelation for rationally designing the structure of GO nanofillers and better exerting its excellent properties in epoxy matrix composites.

进行了分子动力学（MD）模拟，探索了聚（多巴胺）（PDA）改性的氧化石墨烯（GO）的理想结构设计，该结构设计更有助于提高环氧树脂复合材料的性能。将环氧树脂基质与具有不同结构的PDA改性GO（PDA-GO）颗粒复合，包括表面改性和插入层间改性。相互作用能（ē_间），计算了PDA-GO /环氧复合材料不同结构的分子迁移率（MSD），堆积密度（RDF），热和机械性能。有趣的是，发现增加的GO层数削弱了GO颗粒与环氧基质之间的界面结合，并阻止了环氧分子链的紧密堆积，但是具有插入修饰结构的PDA-GO表现出理想的界面结合力。环氧树脂，大大改善了所得复合材料的热和机械性能。另外，使用PDA对单层GO进行表面改性对环氧基复合材料的微观和宏观性能有负面影响。