Preparation and properties of lowest eutectic mixture MTNP/TNAZ

Abstract

ABSTRACT In this work, DSC tests were performed on 1-methyl-3,4,5-trinitropyrazole (MTNP) and 1,3,3-trinitroazetidine (TNAZ) binary eutectic systems with different molar ratios, and we drawn the T-X and H-X phase diagrams. We get the ratio of MTNP/TNAZ eutectic system by phase diagram, and the eutectic of the two were characterized by Energy spectrum analysis(EDS), X-ray diffraction(XRD), fourier transform infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermodynamic analysis, thermo gravimetric mass spectrometry (TG-MS), thermal sensitivity test, mechanical sensitivity test and detonation performance calculation. The results show that the ratio of MTNP/TNAZ eutectic system is 46.3/53.7, and the melting point is 72.58°C. EDS shows that there is no impurities in the lowest eutectic mixture. XRD indicates that there is some intermolecular force between the lowest eutectics mixture, which changes the diffraction peak. IR shows that the raw MTNP and raw TNAZ do not react with each other after forming the lowest eutectic mixture. Thermodynamic analysis indicates that the thermal decomposition reaction of the lowest eutectic mixture requires endotherm, and the entropy value of the reaction is decreased. Thermo gravimetric mass spectrometry (TG-MS) shows that the main decomposition products of the lowest eutectic mixture are CH4, N2O, CO2, H2, H2O, and only a small amount of NH3, and thermal decomposition of it is more complete than raw materials. Then the mechanical sensitivity of the raw MTNP, TNAZ and the lowest eutectic were tested, and the detonation performance were also calculated, the results show that the lowest eutectic has good mechanical sensitivity and detonation performance. Finally, the thermal sensitivity test was carried out on the raw materials and the lowest eutectic mixture, and it was found that the lowest eutectic mixture had the lowest activation energy, which is more conducive to thermal decomposition.