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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 dissolution properties of ammonium dinitramide (ADN) in N-methyl pyrrolidone (NMP) were studied with a RD496-2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. The heat effects were determined for ADN in NMP. The molar enthalpies and the differential molar enthalpies for ADN in NMP were also obtained at the same time. The corresponding kinetic equations that describe the four dissolution processes are discussed. [ABSTRACT FROM AUTHOR]

The enthalpy of dissolution of FOX-12 in dimethyl sulfoxide (DMSO) was measured by means of a RD496-III Calvet microcalorimeter at 298.15 K. Empirical formulae for the calculation of the enthalpy of dissolution ( $$ \Updelta_{\text{diss}} H $$ ), relative partial molar enthalpy ( $$ \Updelta_{\text{diss}} H_{\text{partial}} $$ ), and relative apparent molar enthalpy ( $$ \Updelta_{\text{diss}} H_{\text{apparent}} $$ ) were obtained from the experimental data of the enthalpies of dissolution of FOX-12 in DMSO. The kinetic equation that describes the dissolution process of FOX-12 in DMSO at 298.15 K is determined as $$ \frac{{{\text{d}}\alpha }}{{{\text{d}}t}} = 8.5 \times 10^{ - 3} (1 - \alpha )^{0.59} $$ . [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]

The effects of nano-CuO particles on thermal decomposition behavior of the copolymer of 3,3′-bis(azidomethy) oxetane and glycidyl azide polymer (BAMO–GAP) were investigated by employing DSC–TG–FTIR–MS coupling technique. The results showed that, when the nano-CuO was dispersed into the BAMO–GAP copolymer, the thermal decomposition temperatures of copolymer was decreased, the apparent activation energy was decreased by 11.2 kJ mol −1 and the apparent decomposition heat increased by maximum 12%. The major gaseous products of BAMO–GAP copolymer and BAMO–GAP/CuO were identified. It was suggested that nano-CuO enhanced the N N bond breaking in azido groups and more N 2 was released. Namely, nano-CuO is a marked kind of catalyst, which has a crucial effect on thermal decomposition of BAMO–GAP copolymer. [ABSTRACT FROM AUTHOR]

Highlights: [•] The crystal structure of the new ionic compound DAT·DNBA was determinated and analyzed. [•] The thermal behavior and the decomposition reaction kinetics were investigated by means of DSC and RSFTIR. [•] Some parameters were calculated to evaluate the thermal stability and safety. [ABSTRACT FROM AUTHOR]

Abstract: The specific heat capacity (C p) of 37.2/44/16/2.2/0.2/0.4-GAP/CL-20/Al/N-100/PCA/auxiliaries mixture was determined with the continuous C p mode of microcalorimeter. The equation of C p with temperature was obtained. The standard molar heat capacity of GAP/CL-20/Al/N-100/PCA/auxiliaries mixture was 1.225Jmol−1 K−1 at 298.15K. With the help of the peak temperature (T p) from the non-isothermal DTG curves of the mixture at different heating rates (β), the apparent activation energy (Ek and Eo) and pre-exponential constant (A K) of thermal decomposition reaction obtained by Kissinger''s method and Ozawa''s method. Using density (ρ) and thermal conductivity (λ), the decomposition heat (Q d, taking half-explosion heat), Zhang-Hu-Xie-Li''s formula, the values (T e0 and T p0) of T e and T p corresponding to β →0, thermal explosion temperature (T be and T bp), adiabatic time-to-explosion (t TIad), 50% drop height (H 50) of impact sensitivity, and critical temperature of hot-spot initiation (T cr,hot spot) of thermal explosion of the mixture were calculated. The following results of evaluating the thermal safety of the mixture were obtained: T be =441.64K, T bp =461.66K, t Tlad =78.0s (n =2), t Tlad =74.87s (n =1), t Tlad =71.85s (n =0), H 50 =21.33cm. [Copyright &y& Elsevier]

Abstract: The composite modified double base (CMDB) propellants (nos. RB0601 and RB0602) containing 3,6-bis (1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz) without and with the ballistic modifier were prepared and their thermal behaviors, nonisothermal decomposition reaction kinetics, thermal safety and burning rates were investigated. The results show that there are three mass-loss stages in TG curve and two exothermic peaks in DSC curve for the BTATz-CMDB propellant. The first two mass-loss stages occur in succession and the temperature ranges are near apart, and the decomposition peaks of the two stages overlap each other, inducing only one visible exothermic peak appear in DSC curve during 350–550K. The reaction mechanisms of the main exothermal decomposition processes of RB0601 and RB0602 are all classified as chemical reaction, the mechanism functions are f(α)=(1− α)2, and the kinetic equations are and . The thermal safety evaluation on the BTATz-CMDB propellants was obtained. With the substitution of 26% RDX by BTATz and with the help of the ballistic modifier in the CMDB propellant formulation, the burning rate can be improved by 89.0% at 8MPa and 47.1% at 22MPa, the pressure exponent can be reduced to 0.353 at 14–20MPa. [Copyright &y& Elsevier]

Abstract: The enthalpy of dissolution of 1,1-diamino-2,2-dinitroethylene (FOX-7) in DMSO was measured by means of a RD496-2000 Calvet microcalorimeter at 298.15K. Empirical formulae for the calculation of the enthalpy of dissolution (Δdiss H), relative partial molar enthalpy (Δdiss H partial) and relative apparent molar enthalpy (Δdiss H apparent) were obtained from the experimental data of the enthalpies of dissolution of FOX-7 in dimethyl sulfoxide (DMSO). The dilution/crystallization kinetic behavior of FOX-7 in DMSO/water system was investigated and the kinetic equation describing the dilution/crystallization process was presented. [Copyright &y& Elsevier]