A new 1:1 cocrystal explosive composed of 2,4,­6,8,­10,12-hexanitrohexaazaiso-wurtzitane (CL-20) and 1,4-dinitroimidazole (1,4-DNI) was synthesized through cocrystallization by slow solvent evaporation. The cocrystal has a crystal density of 1.922 g/cm3 at 296 K and belongs to the orthorhombic system with P212121 space group. The properties of the cocrystal including thermal stability, impact sensitivity, and detonation performances were studied. DSC test shows that the cocrystal has a melting point of 115 °C with a decomposition temperature of 253 °C, suggesting an excellent thermal stability. Furthermore, the cocrystal exhibits an impact energy with 50% ignition probability of 10 J, showing a substantial reduction in impact sensitivity compared to pure CL-20 and HMX. Besides, the predicted detonation velocity and detonation pressure of the cocrystal are 9242 m/s and 39.01 GPa, respectively, which are similar to those of HMX. Therefore, the CL-20/1,4-DNI cocrystal may be an attractive high energy explosive with low sensitivity and, thus, may act as a promising explosive candidate instead of HMX for low vulnerability formulations in the future.

A new family of polyoxometalate‐based ionic liquids (POM‐IL) is synthesized, characterized, and employed as catalysts in the esterification of various alcohols with acetic acid. The ionic liquid catalyst shows high activity and gives excellent yields of esters. An emulsion forms between the IL catalyst and substrates during the reaction and promotes the catalytic process. After reaction, the emulsion can conveniently be broken by the addition of a weakly polar organic solvent to facilitate the separation of the catalyst. On the basis of the above results, a direct transformation of benzaldehyde to methyl ester under relatively mild conditions is also developed in the absence of any cocatalyst. Finally, the scope of the substrates and recyclability of the catalyst are also investigated.

The solubility of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in 12 pure solvents was measured in the temperature range of 298.15–358.15 K by the static equilibrium method through high-performance liquid chromatography (HPLC) at the atmospheric pressure, including dimethyl sulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMAC), 1,4-butyrolactone (BL), triethyl phosphate, propylene carbonate, N,N-dimethylformamide (DMF), cyclohexanone, cyclopentanone, acetonitrile, acetone, and pyridine. The experimental solubility data were correlated with three thermodynamic models, including the modified Apelblat model, the Yaws model, and the ideal solution model. Experimental data indicate that the solubility of HMX increases with increasing temperature in all test solvents, and three kinds of thermodynamic models gave satisfactory correlations. All of these results lay the foundation for the crystallization process study of HMX and provide guidance for the use of suitable crystallization methods in different solvents.

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