The thermal behavior of dihydroxylammonium 5,5 0 -bistetrazole-1,1 0 -diolate (TKX-50) was measured by differential scanning calorimetry (DSC), thermal gravimetric analysis-Fourier transform infrared spectroscopy (TG-FTIR) and thermal gravimetric analysisdifferential scanning calorimetry-mass spectrometry (TG-DSC-MS). The critical temperature of thermal explosion (T b ) and the initial decomposition temperature (T p0 ) were determined to be 523.39 and 513.80 K, respectively. The apparent activation energy (E) and preexponential factor (A) of the exothermic decomposition reaction, and activation entropy (DS = ), activation enthalpy (DH = ), activation Gibbs free energy (DG = ) at T P0 of the reaction and the critical temperature of thermal explosion (T b ) were calculated: E K = 237.59 kJ mol -1 , E O = 234.11 kJ mol -1 , DS = = 209.83 J K -1 mol -1 , DH = = 233.32 kJ mol -1 , DG = = 126.53 kJ mol -1 . TG-DSC-FTIR/MS analysis of thermal decomposition products of TKX-50 reveals that the main decomposition products are N 2 , H 2 O, NH 3 , NH 2 , N 2 O and NO.

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Lead-based primary explosives were widely applied in military and civilian ammunition, which have subsequently caused serious environmental and health-related problems. Therefore, the development of green alternatives for the lead-based primary explosives has been one of the major focuses in the field of energetic materials. Four potassium salts based on nitraminofurazan have been easily synthesized and show excellent comprehensive performances. Among them, potassium 3-dinitromethyl-4-nitraminofurazan (K DNMNAF, 1) showed better thermal stability (T : 281.4 °C), higher density (2.174 g cm ), and lower friction sensitivities (72 N) than that of potassium 4,5-bis(dinitromethyl)furoxanate (K BDNMF, T : 218.3 °C, density: 2.130 g cm , FS: 5 N, P: 27.3 GPa, v : 7759 m s ); furthermore, it displayed comparable detonation performances (P: 27.2 GPa, v : 7758 m s ). The promising properties of these salts make this kind of material a competitive alternative to lead azide as a primary explosive.

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3,4-Diaminofurazan was conveniently converted into energetic salts of 3,4-dinitraminofurazan that were paired with nitrogen-rich cations in fewer than three steps. Seven energetic salts were prepared and fully characterized by multinuclear ((1) H, (13) C) NMR and IR spectroscopy, differential scanning calorimetry (DSC), and elemental analysis. In addition, the structures of the ammonium salt (2), hydrazinium salt (4), hydroxylammonium salt (5), aminoguanidinium salt (7), diaminoguanidinium salt (8) and triaminoguanidinium salt of 3,4-dinitraminofurazan (9) were further confirmed by single-crystal X-ray diffraction. The densities of these salts were between 1.673 (8) and 1.791 g cm(-3) (5), whilst their oxygen balances were between -48.20 % (9) and -6.25 % (5). These salts showed high thermal stabilities, with decomposition temperatures between 179 (5) and 283 °C (6). Their sensitivities towards impact and friction were measured by BAM equipment to be between <1 J (9) and >40 J (6-8) and 64 N (9) and >360 N (6), respectively. The detonation performance of these compounds, which was calculated by using the EXPLO5 program, revealed detonation pressures of between 28.0 (6) and 40.5 GPa (5) and detonation velocities of between 8404 (6) and 9407 m s(-1) (5).

In this study, ultrahigh-molecular-weight polyethylene (UHMWPE) fibres, modified by acetic acid, sulfuric acid and water at a ratio of 20:25:2 for different time periods and modified UHMWPE/EP composites were prepared. The micromorphology, chemical composition, contact angle, H sample extraction, tensile properties and bending performance of the composite material of the UHMWPE fibres before and after modification were tested and analysed. The results show that, after the UHMWPE fibres were treated with the modified liquid, the surface roughness of the fibre increased, the contact angle decreased, and the surface chemical composition and species significantly changed; the mechanical properties of the composites are best when the fibres were treated for 9 min. For the same fibre content, the specific strength, specific modulus and bending load of UHMWPE composites treated for 9 min were increased by 16.7%, 82.9% and 55.3%, respectively, compared with untreated samples.