A molecular dynamics study and detonation parameters calculation of 5,5’-dinitramino-3,3’-bi[1,2,4-triazolate] carbohydrazide salt (CBNT) and its PBXs

Molecular dynamics (MD) simulation has been used to investigate the new explosive 5,5ʹ-dinitramino-3,3ʹ-bi[1,2,4-triazolate] carbohydrazide salt (CBNT) and its polymer-bonded explosives (PBXs) with polymethyl methacrylate (PMMA), polyisobutylene (PIB), cellulose acetate butyrate (CAB) and polyurethane (Estane 5703). The binding energy, isotropic mechanical properties (tensile modulus, bulk modulus, shear modulus, and Poisson’s ratio) and moldability are reported for CBNT and its based PBXs. Moreover, the detonation parameters (detonation velocity, detonation pressure, detonation temperature, and detonation heat) of CBNT and CBNT-based PBXs are calculated using EXPLO5. The binding energy between each of the crystalline surfaces and each polymer is different, of which the descending order is CBNT/CAB > CBNT/Estane5703 > CBNT/PMMA > CBNT/PIB. The obtained mechanical properties results indicate that the mechanical properties of the CBNT can be effectively improved by adding a tiny amount of polymer binders and the ability of different polymer binders improving the plasticity and moldability of CBNT in the descending order of Estane 5703 > CAB > PMMA > PIB. The calculated detonation performances show that when 5% binders are added, the detonation velocity and detonation pressure of PBXs are lower than those of pure CBNT, of which the detonation velocity is higher than 8500 m/s and the detonation pressure is higher than 26 GPa. Due to the high enthalpy of formation, the detonation temperature and detonation heat of CBNT/CAB are larger than those of pure CBNT.