Energetic Materials Frontiers最新文献

To address the issues of high saturated vapor pressure, high toxicity, and high viscosity of TNT, this article used a chemical method to synthesize a new carrier explosive BFTNAN. The prepared samples were characterized using scanning electron microscope(SEM), energy spectrum(EDS), x-ray diffraction(XRD), infrared spectrum(IR), x-ray photoelectron spectroscopy(XPS), nuclear magnetic resonance, and elemental analysis techniques. The enthalpy of formation of BFTNAN was measured using a specialized calorimeter that is specially used in testing of explosives and powders. The thermal decomposition performance of BFTNAN was tested by DSC technology. Meanwhile, the mechanical sensitivity, thermal sensitivity, and detonation performance of BFTNAN based melt-cast explosive was also tested. The results of characterizations showed that the prepared sample was indeed BFTNAN. The enthalpy of formation of BFTNAN was determined as ΔH_f,BFTNAN = −72.6 kJ·mol⁻¹. At a heating rate of 20 °C·min⁻¹, the thermal decomposition peak of BFTNAN is at T_P = 250.6 °C, and the activation energy is E_K = 80 kJ·mol⁻¹, which is closed to the T_p and E_K values of TNT. This indicates that BFTNAN is a relatively easy to decompose explosive, but the decomposition rate is not fast. The critical temperature for thermal explosion of BFTNAN reached T_b = 216 °C, which is also closed to the T_b value of TNT. The impact and friction sensitivity of BFTNAN were lower than those of TNT, which was closed to those of DNAN. The thermal sensitivity of BFTNAN is lower than TNT. The detonation velocity and heat of explosion of BFTNAN based melt-cast explosive were distinctly higher than those of TNT based explosive. Especially, BFTNAN based melt-cast explosive were of the advantages in chemical energy storage, work capacity, brisance, and ability of acceleration metals.

Interfacial strength is a key factor affecting the mechanical properties of materials. This study aims to enhance the mechanical properties of energetic polymer bonded explosives (PBXs) by modifying 1,3,5-triamino-2,4,6-trintrobenzene (TATB) crystals—a typical energetic material—using 2-ureido-41H-6-methyl-pyrimidinone (UPy) derivatives with strong hydrogen-bonding interactions. Specifically, strongly adhesive polydopamine (PDA) was employed to graft UPy-functionalized molecules with isocyanate groups (–NCO) and hydroxyl groups (–OH). Scanning electron microscopy (SEM) images indicate that TATB crystals became rougher after being coated with PDA, while the introduction of UPy did not affect the surface morphology. The presence of urethane bond peaks in the samples indicates that UPy-NCO was successfully grafted onto the PDA. UPy is essentially nonpolar and is prone to bind with binders, having the potential to improve the creep resistance of PBXs. Due to the strong interfacial enhancement by UPy and PDA, the tensile strength and compressive strength of the sample grafted with 1 wt% UPy significantly increased by 35.6 % and 26.5 %, respectively. Theoretical calculations indicate interfacial enhancement by UPy introduction, where the strong hydrogen bonding may produce a positive impact. The successful introduction of UPy modified the nature of TATB and improved its interfacial strength, finally enhancing the mechanical properties of the PBXs. The conditions for the grafting reaction in this study are mild and universal and thus can be applied to other compositions.

Using two routes, this study designed and synthesized a novel azo-linked four-heterocyclic compound, 1,2-bis(5-(1H-tetrazol-5-yl)-4H-1,2,4-triazol-3-yl) diazene (3, H₄BTTD), with high yields. It corroborated that large conjugated planar energetic molecules in energetic compounds, exemplified by H₄BTTD, contribute to the formation of layered crystal stacking based on abundant hydrogen bonds and interlayer π-π interactions. This markedly diminishes the mechanical sensitivities of energetic compounds. Single-crystal X-ray diffraction (XRD) experiments revealed the presence of layered structures in H₄BTTD hydrate, as well as its magnesium-based complex [Mg₂(BTTD)(H₂O)₈] (4) and calcium salt [Ca(H₂O)₇] (H₃BTTD)₂ (5). Based on these structural data, this study analyzed the causes of these layered structures. Furthermore, this study systematically characterized the compounds’ physical and chemical properties, including mechanical sensitivities (IS ≥ 20 J, FS > 360 N), thermal stability (T_d = 253.7–287.8 °C), and detonation performance (D = 6808–8253 m⋅s⁻¹), confirming the influence of molecular structures on the macroscopic properties of energetic materials through crystal stacking. Additionally, pyrotechnic formulas based on compounds 3 and 5 exhibited the most intense light emission within a wavelength range of 658.6–689.8 nm, underscoring the potential application of both compounds as promising candidates in preparing high-purity red pyrotechnic formulation.

Stabilizers play a crucial role in preventing undesirable decomposition and degradation reactions of propellants, thus ensuring their long-term performance and safe storage. This review highlights recent advancements in stabilizer selection and formulation techniques, aiming to enhance the stability of single base nitrocellulose (SB-NC) propellants. It examines several types of stabilizers for SB-NC propellants, including their reaction mechanisms and effectiveness in preventing degradation reactions of the propellants, as well as the effects of their concentrations, particle sizes, and distributions on the propellants’ stability. Furthermore, it explores innovative approaches such as nano and green stabilizers with improved stability and compatibility. This review also provides insights into methods for evaluating the efficiency and propellant stability of the stabilizers, such as thermal analysis and accelerated aging tests. The findings of this review will assist in developing advanced propellant formulations that meet the growing demand for the applications of NC-based propellants.