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Combining the advantages of energetic heterocycles to achieve high-energy insensitive explosives is a significant challenge. Herein, based on high-energy tetrazole rings and highly stable 1,3,4-oxadiazole rings, a series of novel nitrogen rich energetic compounds 5–9 were successfully constructed. The related compounds were fully characterized by EA, FT-IR, NMR, DSC, and MS, and compounds 6–9 were further confirmed by X-ray single crystal diffraction. Among them, the energetic ion salts 6–8 show high thermal stability (Tdec > 250 °C) and low mechanical sensitivity (IS > 40 J, FS > 360 N), as well as good energy properties (7552–8050 m s−1, 19.4–23.3 GPa). In particular, the azo compound 9 exhibits competent comprehensive performances (Tdec = 226.2 °C, D = 8502 m s−1, P = 28.9 GPa, IS = 32 J, FS = 320 N). These results suggest that the strategy of integrating tetrazole and 1,3,4-oxadiazole and employing an azo structure as a bridging unit are effective approaches to construct high-energy insensitive materials. [ABSTRACT FROM AUTHOR]

The design of heat-resistant energetic compounds generally employs symmetry, planarity, and multi-hydrogen bonds to obtain compounds with high density, good thermal stability, and low sensitivity. In this paper, a heat-resistant hydrazine-bridged compound, 6,6′-(hydrazine-1,2-diyl)bis(5-nitropyrimidine-2,4-diamine) (PHP), was designed and synthesized with the strategy of multi-fused conjugated structure constructed by hydrogen bonds. The compound featured high symmetry, high planarity, and strong conjugation with good thermal stability (364 °C). This strategy provides a basis for the design of heat-resistant energetic compounds. [ABSTRACT FROM AUTHOR]

Energetic metal organic frameworks (EMOFs) are increasingly developed and have proven to be candidates for novel high energy density materials (HEDM). Here, two energetic metal complexes based on 3,5-diaminopyrazolone-4-oxime (DAPO) ligands were synthesized by simple steps and fully characterized by NMR and IR spectroscopy, X-ray single-crystal diffraction, and DSC-TG. The detonation performance was calculated using the Kamlet–Jacobs formula. The crystal densities of these complexes (C6H14N12O10Co (2) and C6H14N12O10Cd (3) are as high as 1.945 g cm−3 at 163 K and 2.072 g cm−3 at 298 K, respectively. Thermal analysis by the DSC-TG test shows that they all have good thermal stability with the highest decomposition temperatures of 287 °C and 344 °C, respectively. These two as-synthesized complexes exhibit excellent detonation performance; 2 (D = 8682 m s−1, P = 34.98 GPa) and 3 (D = 8383 m s−1, P = 33.78 GPa) have good detonation velocity and detonation pressure that are superior to those of TNT, which is widely used today. Thus, they show great promise for potential applications as thermally stable energetic materials. [ABSTRACT FROM AUTHOR]

Guided by synthetic chemistry, coordination chemistry and crystallization chemistry, a novel synthesis and crystallization strategy for laser complex energetic materials has been established in this study. In this study, a method with milder reaction conditions was adopted to design the steps and successfully synthesize urazine (H2ur). At the same time, using H2ur as the ligand, the "acid-controlled dissolution-crystallization" method was used to successfully prepare the crystalline coordination polymer Ag(H2ur)NO3 (5), and its 1D structure was confirmed by X-ray single crystal diffraction. The physicochemical property evaluation revealed that 5 has the best performance: insensitive to light, noncorrosive properties to metal shells, excellent tolerance to moisture, good thermal stability, and insensitive to mechanical stimulation. Theoretical calculations show that the compound has acceptable detonation properties (D = 7.6 km s−1, P = 31.83 GPa). In addition, hot-needle experiments show that 5 has a good DDT effect. More importantly, it has great potential for application in laser energetic materials (τ = 300 ms, E = 800 mJ). [ABSTRACT FROM AUTHOR]