Characterization and Testing for Lowest Eutectic Mixture of TNBA/DNTF

Abstract

AbstractIn this work, electrostatic spraying was used to prepare TNBA/DNTF eutectic mixtures with different mass ratios. The T−X phase diagram and the H−X phase diagram were drawn from the DSC curves of the eutectic mixtures. The morphology, composition, structure, thermal decomposition properties, mechanical sensitivity, thermal sensitivity, and detonation properties of the lowest eutectic were characterized by scanning electron microscope (SEM), energy dispersive X‐ray spectroscopy (EDS), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (IR), X‐ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC) and thermogravimetric analysis‐mass spectrometry (TG‐MS), thermal sensitivity tests, mechanical sensitivity tests, and detonation performance calculations. The results showed that the best molar ratio of TNBA to DNTF was 59.41 : 40.59, whereas the best mass ratio was 60.17 : 39.83. The microscopic morphology was free of sharp edges and corners, the component proportions were the same as before electrostatic spraying, the surface elements were evenly distributed, and the crystal structure was essentially the same as those of the raw materials. The melting temperature was 352.0 K, which was 21.0 K and 33.1 K lower than those of the TNBA and DNTF raw materials, respectively. The thermal decomposition reaction rate constant (k), activation energy (EK), and preexponential factor (AK) of the lowest eutectic were 0.398 s−1, 81.34 kJ ⋅ mol−1, and 4.86×107 s−1, respectively. In the lowest eutectic, the component TNBA began to thermally decompose first, followed by DNTF. The main decomposition products of the lowest eutectic were CH4, H2O, H2, CO, N2, NH3, CO2, and N2O, with a small amount of C. The impact sensitivity (H50), friction sensitivity (P), and 5 s explosion temperature (T5s) of the lowest eutectic mixture were 39.7 cm, 28 %, and 563 K, respectively. Its detonation performance (OB=−36.52 %, QD=−4658 kJ ⋅ kg−1, vD=7598.37 m ⋅ s−1) was intermediate between those of TNBA and DNTF. The main detonation products were CO2, N2, CO, C(d), H2O, Br, and CH2O2.