A combined ReaxFF simulation and TG-MS study on the thermal decomposition mechanism of 5,5MODIFIER LETTER PRIME-dinitramino-3,3MODIFIER LETTER PRIME-bi[1,2,4-triazolate] carbohydrazide salt (CBNT)

Thermogravimetry coupled with mass spectrometry (TG-MS) and ReaxFF molecular dynamics (MD) simulations are firstly applied to study the thermal decomposition mechanism of 5,5MODIFIER LETTER PRIME-dinitramino-3,3MODIFIER LETTER PRIME-bi[1,2,4-triazolate] carbohydrazide salt (CBNT). ReaxFF MD simulations are applied to investigate the primary chemical reactions, decomposition products and decomposition rate, respectively. Experimentally, TG-MS techniques are adopted to identify the final gaseous products decomposed by CBNT. Both TG-MS measured results and ReaxFF MD simulated results show that the final stable gaseous products are mainly NH3, H2O, N-2 and CO2. The main intermediates and chemical reactions during the decomposition process are obtained by ReaxFF MD simulations as well. According to the simulation and experimental results, the most probable thermal decomposition path of CBNT is obtained. The initial decomposition step of CBNT is the dissociation of N-NO2 and N-NH3 bonds to generate NO2 and NH3, followed by the cleavage of the C-N bonds, and resulting in the formulation of the ring structure. After the main reactions of carbazide cations and bistriazole anions, high-frequency reactions primarily occur between the unstable intermediate products and finally produces small stable molecules such as NH3, H2O, N-2 and CO2.

Automated summary

Thermogravimetry coupled with mass spectrometry (TG-MS) and ReaxFF molecular dynamics (MD) simulations were used to study the thermal decomposition mechanism of CBNT. The results showed that the final stable gaseous products of CBNT were NH3, H2O, N-2 and CO2. The most probable thermal decomposition path of CBNT was obtained through simulation and experiment.