Molecular dynamics simulation of bilayer core-shell structure of CL-20 surface-modified by polydopamine coated with polymer binder

Insensitive coating materials and coating structures have always been the focus of attention in the field of energetic materials. Molecular dynamics simulation provides convenience for material screening and performance prediction and has been widely used. In this paper, CL-20 was used as the high-energy component of the inner layer, PDA was used as the middle layer, and different polymer binders were selected as the outermost coating material. The simulation analysis of the formed bilayer core-shell structure (CL-20/PDA/Binder) was carried out. It was found that PDA/EVA has a higher Tg as the shell material. Compared with directly coating CL-20 with binder, the interaction energy between CL-20 and binder after PDA surface modification is improved, the maximum stress increase before tensile fracture of each system. When the outermost binder is Hytemp4454, the improvement effect is more obvious, and the interaction energy is the largest, and the Young's modulus of this system is more excellent. Compared with CL-20, the trigger bond length of CL-20/PDA/Hytemp4454 system is significantly reduced after coating CL-20 with double shells. This work provides theoretical guidance for more rational design of CL-20/PDA/Binder system formula and better play of the modification effect of polymers on PBXs.