A series of 3-nitro-5-nitroimino-1,2,4-oxadiazole-based energetic salts were synthesized from 3-nitro-5-nitroimino-1,2,4-oxadiazole anion and nitrogen-rich cations. They were fully characterized by IR,elemental analys...A series of 3-nitro-5-nitroimino-1,2,4-oxadiazole-based energetic salts were synthesized from 3-nitro-5-nitroimino-1,2,4-oxadiazole anion and nitrogen-rich cations. They were fully characterized by IR,elemental analysis and NMR spectroscopy. The structure of triaminoguanidinium salt(1-e) was confirmed by single crystal X-ray diffraction. All salts showed good thermal stability with decomposed temperature ranging from 155 8C to 258 8C, and positive heats of formation from 226.0 k J/mol to554.1 k J/mol. Thus, the theoretic detonation pressure was predicted from 28.70 GPa to 37.60 GPa and velocities from 8526 m/s to 9354 m/s. Among them, guanidinium salt(1-c) exhibited both high decomposition temperature(258 8C) and detonation velocity(9319 m/s).展开更多
The properties of dissolution in different solvents,the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate(1a),1,2,...The properties of dissolution in different solvents,the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate(1a),1,2,3-triazolium nitrate(1b),3,4,5triamino-1,2,4-triazolium nitrate(2a),3,4,5-triamino-1,2,4-triazolium dinitramide(2b)were precisely measured using a Calvet Microcalorimeter.The thermochemical equation,differential enthalpies of dissolution(△difH m ),standard molar enthalpies of dissolution(△difH m ),apparent activation energy(E),pre-exponential constant(A),kinetic equation,linear relationship of specific heat capacity with temperature over the temperature range from 283 to 353 K,standard molar heat capacity(C p,m)and enthalpy,entropy and Gibbs free energy at 283–353 K,taking 298.15 K as the benchmark for 1a,1b,2a and 2b were obtained with treating experimental data and theoretical calculation method.The kinetic and thermodynamic parameters of thermal decomposition reaction,critical temperature of thermal explosion(Tb),self-accelerating decomposition temperature(TSADT)and adiabatic time-to-explosion(t)of 1a,1b,2a and 2b were calculated.Their heat-resistance abilities were evaluated.Information was obtained on the relation between molecular structures and properties of 1a,1b,2a and 2b.展开更多
A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step ...A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step - diazidoglyoxime cyclization is shown. Experimental results show that presence of moisture in reaction mixture leads to product yield decreasing. The reaction temperature is another key parameter affecting product yield. High reaction temperature shows negative influence on the product yield in Klap6tke method. In Tselinskii procedure the yield of product grows with the reaction temperature increasing. For Klap6tke one-pot method, combination of N-methyl-2-pyrrolidone with 1,4-dioxane is the best solvent, whereas Tselinskii one-pot procedure gives high yield of product when combination of toluene with 0.5 equiv, of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) is used. Us- ing optimized conditions one-pot five-step synthesis of TKX-50 starting from glyoxime is successfully performed and scaled up to 50 g.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.21372027 and 21172203)
文摘A series of 3-nitro-5-nitroimino-1,2,4-oxadiazole-based energetic salts were synthesized from 3-nitro-5-nitroimino-1,2,4-oxadiazole anion and nitrogen-rich cations. They were fully characterized by IR,elemental analysis and NMR spectroscopy. The structure of triaminoguanidinium salt(1-e) was confirmed by single crystal X-ray diffraction. All salts showed good thermal stability with decomposed temperature ranging from 155 8C to 258 8C, and positive heats of formation from 226.0 k J/mol to554.1 k J/mol. Thus, the theoretic detonation pressure was predicted from 28.70 GPa to 37.60 GPa and velocities from 8526 m/s to 9354 m/s. Among them, guanidinium salt(1-c) exhibited both high decomposition temperature(258 8C) and detonation velocity(9319 m/s).
基金supported by the National Natural Science Foundation of China (20573098)the Science and Technology Foundation of National Key Lab of Science and Technology on Combustion and Explosion in China (9140C3503030805)
文摘The properties of dissolution in different solvents,the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate(1a),1,2,3-triazolium nitrate(1b),3,4,5triamino-1,2,4-triazolium nitrate(2a),3,4,5-triamino-1,2,4-triazolium dinitramide(2b)were precisely measured using a Calvet Microcalorimeter.The thermochemical equation,differential enthalpies of dissolution(△difH m ),standard molar enthalpies of dissolution(△difH m ),apparent activation energy(E),pre-exponential constant(A),kinetic equation,linear relationship of specific heat capacity with temperature over the temperature range from 283 to 353 K,standard molar heat capacity(C p,m)and enthalpy,entropy and Gibbs free energy at 283–353 K,taking 298.15 K as the benchmark for 1a,1b,2a and 2b were obtained with treating experimental data and theoretical calculation method.The kinetic and thermodynamic parameters of thermal decomposition reaction,critical temperature of thermal explosion(Tb),self-accelerating decomposition temperature(TSADT)and adiabatic time-to-explosion(t)of 1a,1b,2a and 2b were calculated.Their heat-resistance abilities were evaluated.Information was obtained on the relation between molecular structures and properties of 1a,1b,2a and 2b.
文摘A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step - diazidoglyoxime cyclization is shown. Experimental results show that presence of moisture in reaction mixture leads to product yield decreasing. The reaction temperature is another key parameter affecting product yield. High reaction temperature shows negative influence on the product yield in Klap6tke method. In Tselinskii procedure the yield of product grows with the reaction temperature increasing. For Klap6tke one-pot method, combination of N-methyl-2-pyrrolidone with 1,4-dioxane is the best solvent, whereas Tselinskii one-pot procedure gives high yield of product when combination of toluene with 0.5 equiv, of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) is used. Us- ing optimized conditions one-pot five-step synthesis of TKX-50 starting from glyoxime is successfully performed and scaled up to 50 g.