The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate(TEGDN) and nitroglycerin(NG) were investigated by...The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate(TEGDN) and nitroglycerin(NG) were investigated by thermogravimetry(TG) and differential thermogravimetry(DTG), and differential scanning calorimetry(DSC) under the high-pressure dynamic ambience. The results show that the thermal decomposition processes of the mixed nitric ester gun propellants have two mass-loss stages. Nitric ester evaporates and decomposes in the first stage, and nitrocellulose and centralite II(C2) decompose in the second stage. The mass loss, the DTG peak points, and the terminated temperatures of the two stages are changeable with the difference of the mass ratio of TEGDN to NG. There is only one obvious exothermic peak in the DSC curves under the different pressures. With the increase in the furnace pressure, the peak temperature decreases, and the decomposition heat increases. With the increase in the content of TEGDN, the decomposition heat decreases at 0.1 MPa and rises at high pressure. The variety of mass ratio of TEGDN to NG makes few effect on the exothermic peak temperatures in the DSC curves at different pressures. The kinetic equation of the main exothermal decomposition reaction of the gun propellant TG0601 was determined as: dα/dt=1021.59(1-α)3e-2.60×104/T. The reaction mechanism of the process can be classified as chemical reaction. The critical temperatures of the thermal explosion(Tbe and Tbp) obtained from the onset temperature(Te) and the peak temperature(Tp) are 456.46 and 473.40 K, respectively. ΔS≠, ΔH≠, and ΔG≠ of the decomposition reaction are 163.57 J·mol^-1·K^-1, 209.54 kJ·mol^-1, and 133.55 kJ·mol^-1, respectively.展开更多
We compute the thermodynamic and the kinetic properties for the reaction: HCOCN→HCH+CO using the statistical theory and the transition-state theory.The equi- librium constants and the rate coefficients of this reacti...We compute the thermodynamic and the kinetic properties for the reaction: HCOCN→HCH+CO using the statistical theory and the transition-state theory.The equi- librium constants and the rate coefficients of this reaction are also reported here,and the half lives of formyl cyanide at different temperatures are first estimated in this work.展开更多
The thermal behavior, nonisothermal decomposition reaction kinetics and specific heat capacity of nitrate glycerol ether cellulose(NGEC) were determined by thermogravimetric analysis(TGA), differential scanning ca...The thermal behavior, nonisothermal decomposition reaction kinetics and specific heat capacity of nitrate glycerol ether cellulose(NGEC) were determined by thermogravimetric analysis(TGA), differential scanning calori- metry(DSC) and microcalorimetry. The apparent activity energy(Ea), reaction mechanism function, quadratic equa- tion of specific heat capacity(Cp) with temperature were obtained. The kinetic parameters of the decomposition reac- tion are Ea=170.2 kJ/mol and lg(A/s^-l)=16.3. The kinetic equation isf(α)=(4/3)(1-α)[-ln(1-α)]^1/4. The specific heat capacity equation is Cp=1.285-6.276×10^-3T+1.581×10^-5T^2(283 K〈T〈353 K). With these parameters, the thermal safety properties of NGEC were studied, such as the self-accelerating decomposition temperature(TSADT), critical temperature of thermal explosion(Tb) and adiabatic time-to-explosion(tTlad). The results of the thermal safety evalua- tion of NGEC are: TSADV=459.6 K, Tb=492.8 K, tTlad=0.8 S.展开更多
基金the National Natural Science Foundation of China(No.20573098)the Foundation of Key Laboratory of Science and Technology for National Defence of Propellant and Explosive of China(No.9140C3503020605).
文摘The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate(TEGDN) and nitroglycerin(NG) were investigated by thermogravimetry(TG) and differential thermogravimetry(DTG), and differential scanning calorimetry(DSC) under the high-pressure dynamic ambience. The results show that the thermal decomposition processes of the mixed nitric ester gun propellants have two mass-loss stages. Nitric ester evaporates and decomposes in the first stage, and nitrocellulose and centralite II(C2) decompose in the second stage. The mass loss, the DTG peak points, and the terminated temperatures of the two stages are changeable with the difference of the mass ratio of TEGDN to NG. There is only one obvious exothermic peak in the DSC curves under the different pressures. With the increase in the furnace pressure, the peak temperature decreases, and the decomposition heat increases. With the increase in the content of TEGDN, the decomposition heat decreases at 0.1 MPa and rises at high pressure. The variety of mass ratio of TEGDN to NG makes few effect on the exothermic peak temperatures in the DSC curves at different pressures. The kinetic equation of the main exothermal decomposition reaction of the gun propellant TG0601 was determined as: dα/dt=1021.59(1-α)3e-2.60×104/T. The reaction mechanism of the process can be classified as chemical reaction. The critical temperatures of the thermal explosion(Tbe and Tbp) obtained from the onset temperature(Te) and the peak temperature(Tp) are 456.46 and 473.40 K, respectively. ΔS≠, ΔH≠, and ΔG≠ of the decomposition reaction are 163.57 J·mol^-1·K^-1, 209.54 kJ·mol^-1, and 133.55 kJ·mol^-1, respectively.
文摘We compute the thermodynamic and the kinetic properties for the reaction: HCOCN→HCH+CO using the statistical theory and the transition-state theory.The equi- librium constants and the rate coefficients of this reaction are also reported here,and the half lives of formyl cyanide at different temperatures are first estimated in this work.
基金Supported by the Foundation of National Key Laboratory of Science and Technology on Combustion and Explosion of China(No.9140C3503011004)
文摘The thermal behavior, nonisothermal decomposition reaction kinetics and specific heat capacity of nitrate glycerol ether cellulose(NGEC) were determined by thermogravimetric analysis(TGA), differential scanning calori- metry(DSC) and microcalorimetry. The apparent activity energy(Ea), reaction mechanism function, quadratic equa- tion of specific heat capacity(Cp) with temperature were obtained. The kinetic parameters of the decomposition reac- tion are Ea=170.2 kJ/mol and lg(A/s^-l)=16.3. The kinetic equation isf(α)=(4/3)(1-α)[-ln(1-α)]^1/4. The specific heat capacity equation is Cp=1.285-6.276×10^-3T+1.581×10^-5T^2(283 K〈T〈353 K). With these parameters, the thermal safety properties of NGEC were studied, such as the self-accelerating decomposition temperature(TSADT), critical temperature of thermal explosion(Tb) and adiabatic time-to-explosion(tTlad). The results of the thermal safety evalua- tion of NGEC are: TSADV=459.6 K, Tb=492.8 K, tTlad=0.8 S.