Of Hmx And Hmx-based Polymer-bonded Explosive Performance Of The Simulation Study

In this dissertation, by applying the molecular dynamics method and molecular mechanics method, systematic study of the mechanics properties and thermal expansion quotiety of HMX crystal is carried out, and the mechanics properties and interfacial interactions of polymer bonded explosives (PBXs) composed of HMX and a series of polymers is studied.1. Study of applicability of COMPASS force field for HMX crystal is carried out. It is found that COMPASS force field is applicable to P-HMX crystal, and by revising electric charge, the applicability can be further enhanced.2. Molecular dynamics (MD) method using COMPASS force field has been employed to investigate the thermal expansion coefficient of p-HMX crystal. The results show that the thermal expansion of p-HMX crystal along b axis is more than that of other directions.3. MD simulation using COMPASS force field at NVT ensemble is carried out to investigate the interfacial effect of polymer bonded explosives (PBXs) composed of HMX and polyurethane (Estane5703), hydroxy-terminated polybutadine (HTPB), polyethylene glycol (PEG). It is found that the interfacial effect between polymer and HMX is mostly incarnated as intermolecular hydrogen bond composed of hydrogen atoms and oxygen atoms, the intensity of hydrogen bond depend on the electric charge of atoms.4. MD simulation using COMPASS force field at NVT ensemble is carried out to investigate the mechanics properties of polymer bonded explosives (PBXs) composed of HMX and Estane5703, HTPB, PEG. The results show that the mechanical properties of (3-HMX can be improved by adding polymer.5. MD simulation using COMPASS force field at NVT ensemble is carried out to investigate the mechanics properties of polymer bonded explosives (PBXs) composed of HMX and copolymer of vinylidene fluoride and chlorotrifluoroethylene (F2311) and the temperature dependance. The results show that the mechanical properties of p-HMX can be improved by adding a little amount of F2311,and the temperature dependance of the mechanical properties is inapparent at NVT ensemble.