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The compatibility of binders and plasticizers has a significant influence on the properties of polymer-bonded explosives. Molecular dynamics was employed to explore the compatibility between nitrocellulose (NC) with different nitrogen contents and three azido plasticizers by the solubility parameter, mean square displacement, binding energy, radial distribution function (RDF), radius of gyration, and volume distribution. With the increase of nitrogen content, the solubility parameters of NCs decreased and were in good accordance with the reporting results. 1,5-diazido-3-oxapentane (AZDEGDN) had a stronger diffusion ability in NC than that of the other two plasticizers. The introduction of the RDF suggested that the strong interaction between the NC and AZDEGDN mainly came from the hydrogen bonds between hydroxyl groups of NC molecules and the azido in plasticizers. AZDEGDN increased the free volume in NC/AZDEGDN blends, and the mobility of the molecular chains was enhanced, thus the radius of gyration of the NC molecular chains increased. The comprehensive performances demonstrated that AZDEGDN had a strong plasticizing effect on NC because of hydrogen bonds, presenting a potential option for optimizing explosives formulations. [ABSTRACT FROM AUTHOR]

The thermal decomposition characteristics and fuel oxidation mechanism of ammonium dinitramide (ADN)‐based liquid propellant are of great practical significance, but it is difficult to detect the whole intermediates and products using traditional experimental methods. In this paper, the thermal decomposition of ADN‐based liquid propellant at different temperatures (1500, 2000, 2500, and 3000 K) was simulated using the reactive molecular dynamics method. The effect of temperature on the thermal decomposition of propellant and the distribution of the main products were investigated. The results showed that the temperature played a role in promoting the decomposition of propellant. The main products of ADN‐based liquid propellant were N2, H2O, NH3, HNO3, ⋅NHO, CH2O, CO2, and NO2, while their evolution and generation pathways were also described in detail. The initial decomposition of ADN was the breakage of N−H bonds in ⋅NH4 or N−N/N−O bonds in ⋅N(NO2)2, and methanol generated free radicals by dehydrogenation. There was no direct chemical reaction between ADN and methanol, and the interaction was accomplished through the generation and consumption of free radicals. H2O provided a large amount of ⋅H and ⋅HO leading to a lower activation energy of ADN in propellant than that from reference. The overall reaction mechanism of the liquid propellant was deduced. The results would help to further investigate the reaction mechanism of ADN‐based liquid propellants. [ABSTRACT FROM AUTHOR]