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The dissolution properties of 2-oxo-1,3,5-trinitro-1,3,5-triazacyclohexane (Keto-RDX) in dimethyl sulfoxide (DMSO) were studied by using a RD496-2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. The heat effects, molar enthalpies (ΔdissH), and differential enthalpies (ΔdifH) of dissolution were determined. Furthermore, the corresponding kinetic equations describing the dissolution processes at the four experimental temperatures are dα/dt = 10−2.43 (1 − α)0.63 (T = 298.15 K), dα/dt = 10−2.41 (1 − α)0.67 (T = 303.15 K), dα/dt = 10−2.40 (1 − α)0.75 (T = 308.15 K), and dα/dt = 10−2.38 (1 − α)0.76 (T = 313.15 K). The determined values of the activation energy E and pre-exponential factor A for the dissolution process are 5.99 kJ mol−1 and 10−1.38 s−1, respectively. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of dihydroxylammonium 5,5′-bistetrazole-1,1′- diolate (TKX-50) were studied by using a C-500 type Calvet microcalorimeter at five heating rates. The kinetic and thermodynamic parameters of the first decomposition reaction were obtained. The specific heat capacity of TKX-50 was determined with a Micro-DSCIII calorimeter, and the specific heat capacity equation and the molar specific heat capacity at 298.15 K were also obtained. The self-accelerating decomposition temperature and the critical temperature of thermal explosion are 466.17 and 475.36 K, respectively. The adiabatic time-to-explosion is calculated to be a certain value between 112.65 and 113.93 s. [ABSTRACT FROM AUTHOR]

The thermal decomposition behavior of composite modified double-base propellant containing hexanitrohexaazaisowurtzitane (CL-20/CMDB propellant) was studied by microcalorimetry. The kinetic and thermodynamic parameters were obtained from the analysis of the heat flow curves. The effect of different proportion of CL-20 to the thermal decomposition behavior, kinetics, and thermal hazard was investigated at the same time. The critical temperature of thermal explosion ( T), the self acceleration decomposition temperature ( T), and the adiabatic decomposition temperature rise (Δ T) were calculated to evaluate the thermal hazard of the CL-20/CMDB propellant. It shows that the CMDB propellant with 38% CL-20 has relative lower values of E and lg A, and with 18% CL-20 has the highest potential hazard. [ABSTRACT FROM AUTHOR]

A new energetic zinc-FOX-7 complex, Zn(NH)(FOX-7) (FOX-7 = 1,1-diamino-2,2-dinitroethylene), was first synthesized. Thermal decomposition behavior and nonisothermal decomposition kinetics of Zn(NH)(FOX-7) were studied with DSC and TG/DTG methods. The kinetic equation obtained is $$ \frac{{{\text{d}}\alpha }}{{{\text{d}}T}} = \frac{{10^{13.99} }}{\beta }4(1 - \alpha )[ - \ln (1 - \alpha )]^{{{3 \mathord{\left/ {\vphantom {3 4}} \right. \kern-0pt} 4}}} \exp ( - 1.448 \times 10^{5} /RT) $$ . The self-accelerating decomposition temperature ( T) and critical temperature of thermal explosion ( T) are 183.2 and 195.8 °C, respectively. The specific-heat capacity of Zn(NH)(FOX-7) was determined with a micro-DSC method, and the molar-heat capacity is 454.6 J mol K at 298.15 K. Adiabatic time-to-explosion was also estimated to be about 20 s. The thermal stability of Zn(NH)(FOX-7) is good and higher than that of analogous Cu(NH)(FOX-7). [ABSTRACT FROM AUTHOR]

A new high-energy organic potassium salt, 1-amino-1-hydrazino-2,2-dinitroethylene potassium salt [K(AHDNE)], was synthesized by reacting of 1-amino-1-hydrazino-2,2-dinitroethylene (AHDNE) and potassium hydroxide in methanol aqueous solution. The thermal behavior of K(AHDNE) was studied using DSC and TG/DTG methods and can be divided into three obvious exothermic decomposition processes. The decomposition enthalpy, apparent activation energy and pre-exponential factor of the first decomposition process were −2662.5 J g, 185.2 kJ mol and 10 s, respectively. The critical temperature of thermal explosion of K(AHDNE) is 171.38 °C. The specific heat capacity of K(AHDNE) was determined using a micro-DSC method, and the molar heat capacity is 208.57 J mol K at 298.15 K. Adiabatic time-to-explosion of K(AHDNE) was also calculated. K(AHDNE) presents higher thermal stability than AHDNE. [ABSTRACT FROM AUTHOR]

novel energetic material, 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine (DDNI), was synthesized by the reaction of FOX-7 and glyoxal in water at 70 °C. Thermal behavior of DDNI was studied with DSC and TG-DTG methods, and presents only an intense exothermic decomposition process. The apparent activation energy and pre-exponential factor of the decomposition reaction were 286.0 kJ mol and 10 s, respectively. The critical temperature of thermal explosion of DDNI is 183.78 °C. Specific heat capacity of DDNI was studied with micro-DSC method and theoretical calculation method, and the molar heat capacity is 217.76 J mol K at 298.15 K. The adiabatic time-to-explosion was also calculated to be a certain value between 14.54 and 16.34 s. DDNI presents lower thermal stability, for its two ortho-hydroxyl groups, and its thermal decomposition process becomes quite intense. [ABSTRACT FROM AUTHOR]

The effects of aluminum (Al) and nickel (Ni) powders of various grain sizes on the thermal decomposition of ammonium perchlorate (AP) were investigated by TG and DSC in a dynamic nitrogen atmosphere. The TG results show that Al powders have no effect on the thermal decomposition of AP at conventional grain size, while the nanometer-sized Ni powders (n-Ni) have a great influence on the thermal decomposition of AP with conventional and superfine grain size. The results obtained by DSC and an in situ FTIR analysis of the solid residues confirmed the promoting effects of n-Ni. The effects of n-Ni have been ascribed to its enhancement on the gas phase reactions during the second step decomposition of conventional grain size AP. [ABSTRACT FROM AUTHOR]