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6b-Nitrohexahydro-2H-1,3,5-trioxacyclopenta[cd]-pentalene-2,4,6-triyltrinitrate (NHTPN) is an energetic compound with interesting properties. Its thermal and kinetic behaviors were studied by differential scanning calorimetry (DSC), and its specific heat capacity (Cp) was determined by a continuous Cp mode of microcalorimetry (Micro-DSC III). In order to evaluate its thermal safety, the values (Te0 and Tp0) of Te and Tp corresponding to β → 0, critical temperature of thermal explosion (Tbe and Tbp), adiabatic time-to-explosion (tTIad), 50% drop height (H50) of impact sensitivity, critical temperature of hot-spot initiation (Tcr), thermal sensitivity probability density function [S(T)] vs. temperature (T) relation curves for NHTPN with radius of 1 m surrounded with ambient of 340 K, the peak temperature corresponding to the maximum value of S(T) vs. T relation curve (TS(T)max), safety degree (SD) and critical ambient temperature (Tacr) of thermal explosion of NHTPN were calculated respectively, by means of the onset temperature (Te) and maximum peak temperature (Tp) from the non-isothermal DSC curves of NHTPN at different heating rates (β), the apparent activation energy (EK and EO) and pre-exponential constant (AK) of thermal decomposition reaction obtained by Kissinger's method and Ozawa's method, Cp, density (ρ) and thermal conductivity (λ), the decomposition heat (Qd, taking half-explosion heat), Zhang–Hu–Xie–Li's formula, Smith's equation, Friedman's formula, Bruckman–Guillet's formula, Frank-Kamenetskii formula and Wang–Du's formulas.

The effects Fe 2 O 3 nanoparticles on the thermal decomposition of nitrocellulose (NC) have been investigated by the differential scanning calorimetry (DSC) method and the thermogravimetry with Fourier transform infrared analysis (TG-IR). DSC analysis shows that Fe 2 O 3 can be safely used with NC, and the thermal decomposition reactions of Fe 2 O 3 -NC composite and NC follow the same thermal decomposition mechanism of Avrami-Erofeev equation f(α) = 1.5(1–α)[–ln(1–α)] 1/3 in differential form. The as-prepared nanoparticles could reduce the activation energy of the decomposition reaction and the critical temperature of thermal explosion of NC. In addition, TG-IR analysis indicated that Fe 2 O 3 nanoparticles play a crucial role in promoting the O NO 2 bond cleavage and secondary autocatalytic reactions in condensed phase. This contribution suggests that introducing Fe 2 O 3 nanostructure may be a promising way to accelerate the thermal decomposition of NC.

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.

The thermal behavior of N-2′,4′-dinitrophenyl-3,3-dinitroazetidine (DNPDNAZ) was studied under a non-isothermal conditions by DSC and TG/DTG methods. The apparent activation energy (Ea) and pre-exponential factor (A) of the intense exothermic decomposition reaction of DNPDNAZ were 172.26 kJ · mol−1 and 1013.15 s−1, respectively. The specific molar heat capacity (Cp,m) of DNPDNAZ was determined by a continuous Cp mode of microcalorimetry and theoretical calculation. The detonation velocity (D) and pressure (P) of DNPDNAZ were estimated using the nitrogen equivalent equation according to the experimental density. The free radical signals of DNPDNAZ and 1,3,3-trinitroazetidine (TNAZ) were detected by electron spin resonance (ESR) technique, which is used to estimate their sensitivity.

3,5-Dinitrobenzoic acid of 3,5-diamino-1,2,4-triazole (DAT) salt (DAT·DNBA) was synthesized and its structure was characterized by element analysis, IR and single-crystal X-ray diffraction analysis. The thermal behavior was investigated with the methods of differential scanning calorimetry (DSC) and rapid scan Fourier transform infrared spectroscopy (in situ thermolysis/RSFTIR), and the thermal decomposition reaction kinetics was obtained by means of DSC technique at the different heating rate. The results show that there are two mass loss stages at the thermal decomposition process, and the apparent activation energy and pre-exponential factor of the exothermic decomposition reaction of DAT·DNBA obtained by five integral methods (General integral, MacCallum–Tanner, Satava–Sestak, Agrawal, Flynn–Wall–Ozawa) and one differential method (Kissinger) are 226.37 kJ mol−1 and 1014.51 s−1 in the second decomposition stage. According to the change of the bond intensities, it can be deduced that hydronitrogen, oxynitride, and carbonitride should appear in the gaseous products breaking away from the condensed phase of DAT·DNBA. The groups of nitryl, amido and carboxyl have main contribution to some properties of the compound from the result of the quantum chemical calculation. The self-accelerating decomposition temperature (TSADT), thermal ignition temperature (TTIT) and the critical temperatures of thermal explosion (Tb) and the adiabatic time-to-explosion (tTIAD) is obtained as 660.25 K, 677.16 K, 691.70 K and 236 s, respectively. The detonation velocity (D) and pressure (p) were also estimated as 8358.86 m s−1 and 30.19 GPa. The above-mentioned information is quite useful for analysis and evaluating the stability and thermal safety of DAT·DNBA.

A new high-energy organic potassium salt, 2-(dinitromethylene)-1,3-diazepentane potassium salt K(DNDZ), was synthesized by reacting of 2-(dinitromethylene)-1,3-diazepentane (DNDZ) and potassium hydroxide. The thermal behavior and non-isothermal decomposition kinetics of K(DNDZ) were studied with DSC, TG/DTG methods. The kinetic equation is dα dT = 10 13.92 β 3(1 ― α)[―ln(1 ― α)]2 3 exp(―1.52 x 10 5 /RT). The critical temperature of thermal explosion of K(DNDZ) is 208.63 °C. The specific heat capacity of K(DNDZ) was determined with a micro-DSC method, and the molar heat capacity is 224.63 J mol ―1 K ―1 at 298.15 K. Adiabatic time-to-explosion of K(DNDZ) obtained is 157.96 s.

The thermal behavior of 4-amino-1,2,4-triazol-5-one (ATO) was studied under non-isothermal condition by DSC method in a sealed cell of stainless steel. The melting enthalpy and melting entropy of ATO are 21.34 ± 0.49 kJ mol −1 and 46.54 ± 0.30 J mol −1 K −1 , respectively. The kinetic parameters were obtained from the analysis of DSC curves by Kissinger method, Ozawa method, the differential method and the integral method. The main exothermic decomposition reaction mechanism of ATO is classified as nucleation and growth, and the kinetic parameters of the reaction are E a = 119.50 kJ mol −1 and A = 10 9.03 s −1 . The gas products and condensed phase products of the thermal decomposition of ATO were studied on two simultaneous devices of the fast thermolysis reaction cell (gas reaction cell) in situ in conjunction with rapid scan transform infrared spectroscopy (RSFT-IR) and the solid reaction cell in situ . The heat of formation (HOF) for ATO was evaluated by G3 theory. The detonation velocity ( D ) and detonation pressure ( P ) were estimated by using the well-known Kamlet–Jacobs equation, based on the theoretical HOF and the determined crystal density.

Thermal behavior under pressures of 0.1, 4, and 7 MPa and non-isothermal decomposition reaction kinetics under pressures of 4 and 7 MPa of the composite modified double base propellant containing hexanitrohexaazaisowurtzitane (CL-20-CMDB propellant) were investigated by differential scanning calarimetry (DSC) and thermogravimetry (TG). The results showed that there were three exothermic peaks on DSC curve and three mass loss stages on TG curve under 0.1 MPa. There was only one exothermic peak on the DSC curve under 4 and 7 MPa. The exothermic peak temperatures under 4 and 7 MPa increased with increasing the heating rate. The exothermic decomposition reaction mechanism and kinetic parameters of the propellant changed little with testing surroundings. The reaction mechanism was random nucleation and then growth. The kinetic equations of exothermical decomposition reaction can be expressed as, dα/dt=10^14.5(l-α)[-1n(1-α)](superscript 1/3)e(superscript -17981.7/T) (under 4 MPa) and dα/dt=10^14.7(1-α)•[-1n(l-α)](superscript 1/3)e(superscript -18138.1/T) (under 7 MPa).

The decomposition reaction kinetics of the double-base (DB) rocket propellant composed of the mixed ester of triethyleneglycol dinitrate (TEGDN) and nitroglycerin (NG), and nitrocellulose (NC) with lanthanum citrate as a combustion catalyst was investigated by thermogravimetry and differential thermogravimetry (TG-DTG), and differential scanning calorimetry (DSC) under atmospheric pressure and flowing nitrogen gas conditions. The results showed that the thermal decomposition processes of DB propellant had two mass loss stages: volatilization and decomposition of the mixed ester in the first-stage and exothermic decomposition reaction in the second-stage. The exothermic decomposition reaction mechanism obeyed the third-order chemical reaction rule. The kinetic parameters of the reaction were: Ea=231.14 kJ·mol–1, A=1023.29 s–1. The kinetic equation can be expressed as: dα/dt=1022.99(1–α)3e–2.78×104/T. The critical temperatures of the thermal explosion of the DB propellant obtained from the onset temperature (Te) and the peak temperature (Tp) were: Tbe=463.62 K, Tbp=477.88 K. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) of the reaction were 219.75 J·mol–1·K–1, 239.23 kJ·mol–1, and 135.96 kJ·mol–1, respectively.