Reactive Molecular Dynamics Study on the Effect of H₂O on the Thermal Decomposition of Ammonium Dinitramide

Abstract

Ammonium dinitramide (ADN) is a halogen-free green oxidizer, which is widely used in energetic materials because of its positive oxygen balance and low characteristic signal. However, ADN is easy to absorb moisture, which affects its storage and safety performances. It is of great significance to study the effect of water on its thermal decomposition mechanism. In this paper, the thermal decomposition processes of the ADN with water contents of 0 %, 1 %, 2 %, 5 %, and 10 % are simulated by large-scale reactive molecular dynamics simulations. The reaction pathway and the evolution of the main products are analyzed in detail. The results show that the ADN is not stable and decompose easily, namely ADN!NH 3 (NH 4) + HN 3 O 4 (N 3 O 4). The H 2 O has a significant effect on the thermal decomposition of the ADN. The water contents of 2 % and 5 % can better promote the decomposition of the ADN and the degree of decomposition is also more thorough.

Insight into thermal decomposition behavior of ammonium dinitramide‐based liquid propellant through reactive molecular dynamics simulations

“…A product is defined as the main product when its maximum occurrence frequency exceeds 5 times in the whole decomposition process and its lifetime exceeds 20 ps [13]. According to the analysis of the simulation results, the main decomposition products of ADN‐based liquid propellant were N 2 , H 2 O, NH 3 , NO 2 , CH 2 O, HNO 3 , ⋅NHO, and H 2 at different temperatures.…”

“…20 ps [13]. According to the analysis of the simulation results, the main decomposition products of ADN-based liquid propellant were N 2 , H 2 O, NH 3 , NO 2 , CH 2 O, HNO 3 , •NHO, and H 2 at different temperatures.…”

“…Zeng et al. [13] simulated the thermal decomposition process of ADN with the water content of 0 %, 1 %, 2 %, 5 %, and 10 % by means of ReaxFF‐MD, and analyzed the reaction pathways and evolution of main products in detail. Gonçalves et al.…”

“…With the rapid improvement of computing power and the development of new algorithms, coupled with the challenges of obtaining the reaction mechanism for some free radicals and observing the detailed reaction pathway, the reaction force field based on molecular dynamics (ReaxFF-MD) simulation is playing an increasingly important role in studying thermal decomposition at the atomic level. Zeng et al [13] simulated the thermal decomposition process of ADN with the water content of 0 %, 1 %, 2 %, 5 %, and 10 % by means of ReaxFF-MD, and analyzed the reaction pathways and evolution of main products in detail. Gonçalves et al [14] analyzed the thermal decomposition mechanism, main reactions, and combustion products of ADN and ADN/glycidyl azide through reaction force field (ReaxFF).…”

First principle study and Hirshfeld surface analysis on the effect of type, number, and position of small molecules on the structural stability and optical property of a powerful energetic crystal 6-nitro-7-azido-pyrazol[3,4-d][1,2,3]triazine-2-oxide

“…In addition, the hot H 2 O was found that can catalyze the decomposition of pentaerythritol tetranitrate 13 and furoxan 14 by transporting oxygen between reaction centers under extremely high temperature/pressure, and the content of H 2 O was found to affect the thermal decomposition of ammonium dinitramide. 15 Our previous work 16 found that the H 2 O can stabilize the crystal structure and reduce the impact insensitivity of ICM-102 by enhancing the hydrogen bonding and other intermolecular interactions. H 2 O will also improve the density, mechanical performance, and thermodynamics parameters of ICM-102.…”