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Ni(NH3)4(AFT)2 [NiC6H16N18O2, AFT = 4-amino-3-(5-tetrazolate)furazan] is synthesized and characterized by elemental analysis and Fourier-transform infrared spectroscopy for the first time. X-ray diffraction measurements are used to determine the crystal structure of compound 1. The results demonstrate that compound 1 crystallized in the orthorhombic crystal system. The nickel(II) ion is six-coordinated by N atoms from two AFT-ligands and four NH3 molecules. Its thermal properties are investigated by differential scanning calorimetry and thermogravimetry-derivative thermogravimetry methods, with the results demonstrating that the differential scanning calorimetry curve exhibits two endothermic and one exothermic processes. The endothermic processes are in the range of 130–510 °C with a peak temperature of 188 °C. The temperature from 230 to 400 °C is the exothermic process in which the peak temperature is 314.58 °C. In addition, Kissinger's and Ozawa-Doyle's methods are used for calculating the non-isothermal kinetics parameters. Moreover, the apparent activation energy (E), safety, and thermal stability parameters (T SADT, T TIT, T b) for Ni(NH3)4(AFT)2 are calculated. In addition, the calculated thermodynamic functions (∆S ≠, ∆H ≠, and ∆G ≠) for the exothermic decomposition process of Ni(NH3)4(AFT)2 are 55.07 J mol−1 K−1, 196.18 kJ mol−1, and 164.90 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]

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Three high-energy salts ( 3 , 4 and 5 ) based on oxy-bridged bis( gem -dinitro) furazan with potassium and nitrogen-rich cations were reported. Their structures were fully characterized and confirmed by NMR ( 1 H, 13 C), IR spectroscopy, elemental analysis and single crystal X-ray diffraction. The thermal decomposition behaviors were studied by DSC and TG methods. And, the decomposition process of 5 was studied by the thermolysis in-situ rapid-scan FTIR. The non-isothermal kinetics parameters were obtained by Kissinger’s and Ozawa’s methods, respectively. The activation entropy (Δ S ≠ ), activation enthalpy (Δ H ≠ ), activation Gibbs free energy (Δ G ≠ ) and the critical temperature of thermal explosion were calculated. [ABSTRACT FROM AUTHOR]

A new cadmium complex of 1,1-diamino-2,2-dinitroethylene (FOX-7) was synthesized and structurally determined. Central Cd2+is coordinated by six nitrogens from four NH3molecules and two FOX-7?anions to form an octahedral structure. The thermal decomposition of Cd(NH3)4(FOX-7)2was studied with differential scanning calorimeter and TG–DTG methods. The apparent activation energy and pre-exponential constant of the exothermic process are 220.6 kJ M?1and 1017.86s?1, respectively. Cd(NH3)4(FOX-7)2is sensitive. [ABSTRACT FROM AUTHOR]

Highlights: [•] DHDNEBa was firstly synthesized by the process of metathesis reaction with a yield of 95.7%. [•] The most probable kinetic model function of the exothermic decomposition reaction was deduced. [•] ΔS ≠, ΔH ≠,ΔG ≠, T SADT and T b of DHDNEBa were investigated. [•] The thermal decomposition mechanism of DHDNEBa was studied by means of thermolysis/RSFTIR and TG–MS technologies. [ABSTRACT FROM AUTHOR]

Highlights: [•] Guanidinium azotetrazolate was prepared by using replacement reaction. [•] Thermal decomposition of guanidinium azotetrazolate was separated into two steps. [•] The thermal behaviors of guanidinium azotetrazolate were described. [•] The thermal decomposition mechanisms of guanidinium azotetrazolate were obtained. [Copyright &y& Elsevier]

A new energetic zinc-FOX-7 complex (FOX-7 = 1,1-diamino-2,2-dinitroethylene), Zn(NH3)2(FOX-7)2, was synthesized and structurally characterized by single crystal X-ray diffraction. Zn2+was coordinated by four nitrogens from two ammonias and two FOX-7?anions, forming a distorted tetrahedron. Thermal decomposition of Zn(NH3)2(FOX-7)2was studied by differential scanning calorimetry and thermogravimetry/differential thermogravimetry. The apparent activation energy and pre-exponential constant of the first decomposition process are 144.8 kJ M?1and 1013.99?s?1, respectively. The self-accelerating decomposition temperature and critical temperature of thermal explosion of Zn(NH3)2(FOX-7)2are 183.2 and 195.8?°C, respectively. The thermal stability of Zn(NH3)2(FOX-7)2is good, but Zn(NH3)2(FOX-7)2is still sensitive. [ABSTRACT FROM PUBLISHER]

Highlights: [•] 4-Amino-3,5-dinitropyrazole potassium salt (ADNPK) of a novel energetic flame suppressor was synthesized. [•] The single crystal of ADNPK was determined by single crystal X-ray diffraction. [•] The thermal behavior and non-isothermal decomposition reaction kinetics of ADNPK were studied by nonisothermal DSC. [ABSTRACT FROM AUTHOR]

Two new copper complexes, [Cu(phen)2F0X-7](phen)N03-4H20 and [Cu(phen)2F0X-7]Cl-3H20 (phen = 1,10-phenanthroline monohydrate; FOX-7 = l,l-diamino-2,2-dinitroethylene) were synthe-sized and structurally characterized. Single crystal X-ray diffraction shows that Cu(II) in the two complexes has similar five-coordinate structure, including four nitrogens from two phen and one nitrogen from FOX-7 anion. Thermal decomposition behaviors of the two complexes were studied with differential scanning calorimetry and thermogravimetry/differential thermo-gravimetry methods. The apparent activation energies and pre-exponential constants of the main exothermic decomposition reaction for the two complexes are 208.1 and 183.1 kj mol-1, 1022.99 and 1019.19 s-1, respectively. The self-accelerating decomposition temperature and critical tem-perature of thermal explosion for the two complexes are 152.64 and 162.17°C, 161.50 and 173.29°C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The thermal decomposition behaviors of 3,4,5-triamino-1,2,4-triazole nitrate were studied using a C-500 type Calvet Micro-calorimeter at four different heating rates. Its apparent activation energy and pre-exponential factor of exothermic decomposition reaction are 137.16kJmol−1 and 1010.03 s−1. The critical temperature of thermal explosion is 441.37K. The entropy of activation (ΔS ≠ ), enthalpy of activation (ΔH ≠ ), and free energy of activation (ΔG ≠ ) of the decomposition reaction are −65.65Jmol−1 K−1, 132.97kJmol−1 and 166.35kJmol−1, respectively. The self-accelerating decomposition temperature (T SADT) is 429.56K. The specific heat capacity was determined with a Micro-DSC method and a theoretical calculation method. Specific heat capacity (Jg−1 K−1) equation is C p =0.356+2.957×10−3 T (283.1K< T <353.2K). The adiabatic time-to-explosion is calculated to be a certain value between 702.22s and 712.22s. The critical temperature of Hot-Spot initiation is 600.325°C, and the characteristic drop height of impact sensitivity (H 50) is 27cm. [Copyright &y& Elsevier]

Eight alkaline and alkaline-earth compounds derived from 2,4-dinitroimidazole (2,4-HDNI) were synthesized and characterized by elemental analysis, FT-IR, and TG-DSC, of which K(2,4-DNI) (1), Rb(2,4-DNI)(2,4-HDNI)(H2O)2 (2), and Ba(2,4-DNI)2(H2O)4 (3) were characterized by single-crystal X-ray diffraction analysis. All the three compounds were crystallized from water, but 1 was an anhydrate. The coordination number in 1 and 3 is 10, but in 2 is 9. The 2,4-DNI adopts either η3, η2, or η1 coordination modes depending on the metal cation. In 3, there is an inversion center located on the metal. Only in 2 does water play an important role for the construction of the structure; in 3 it is a hydrogen bonding participant. TG-DSC analyses of 1 were also performed, and non-isothermal decomposition reaction kinetics were obtained. [ABSTRACT FROM AUTHOR]

Three neodymium compounds, Nd(4DNP)3(C2H5OH)3 (1), Nd(4DNPO)3 · 7H2O (2), and {[Nd(μ-ox)(4DNPO)(H2O)4] · 4H2O}n (3) (4HDNP, 3,5-dinitropyrid-4-one; 4HDNPO, 3,5-dinitropyrid-4-one-N-hydroxide; ox, oxalate), were synthesized and characterized by FT-IR, elemental analysis, thermogravimetry-differential scanning calorimetry (TG-DSC), and two of them by single-crystal X-ray diffraction analyses. The results revealed that in 1, the Nd(III) is surrounded by three chelating ligands and three ethanol solvent molecules. The structure of 3 could be described as 1-D chains in which Nd is bis-bidentately bridged by oxalates, together with a monodentate 3,5-dinitropyrid-4-onate N-oxide 4DNPO ligand and four water molecules as well as four uncoordinated water molecules in the crystal lattice. The origin of the oxalate anions in 3 is probably due to decomposition of the 4DNPO or its oxidation of other species. The TG-DTG (DTG, derivative thermogravimetry) and DSC analyses showed that 1 underwent a three-stage decomposition process. A kinetic equation for decomposition reaction of 2 was also obtained. The apparent activation energy (Ea) and pre-exponential factor (A) of the main decomposition reaction are 157.70 kJ mol-1 and 1011.97 s-1, respectively. The kinetic equation can thus be expressed as dα/dt = 1011.97(1 - α)e-1.90 × 104/T. [ABSTRACT FROM AUTHOR]

Abstract: The thermal behavior and decomposition kinetics of C4-bonded PBXs based on some attractive cyclic nitramines were investigated by means of nonisothermal TG and DSC techniques. It has been shown that only a single decomposition process has been observed for RDX-C4 while an obvious two-step process for mixture of BCHMX-C4 CL-20-C4, and HMX-C4. The onset temperature of the exotherms were observed at 216.3, 238.7, 279.2 and 236.7°C with the peak temperatures of 235.1, 279.0, 231.2 and 233.7°C for RDX-C4, BCHMX-C4, HMX-C4 and CL-20-C4, respectively. Their corresponding exothermic decompostion processes were covered by energy changes of 1749, 1938, 1213 and 2639Jg−1, which are lower than that of their pure cyclic nitramines. It was also proved that C4 matrix has significant effect on the activation energy distribution of RDX, BCHMX and CL-20, whose initial autocatalysis effect was inhibited or weakened. With regard to HMX-C4, the activation energy of its initial step is much lower than that of the second step. [Copyright &y& Elsevier]

Ni(NH3)4(AFT)2 [NiC6H16N18O2, AFT = 4-amino-3-(5-tetrazolate)furazan] is synthesized and characterized by elemental analysis and Fourier-transform infrared spectroscopy for the first time. X-ray diffraction measurements are used to determine the crystal structure of compound 1. The results demonstrate that compound 1 crystallized in the orthorhombic crystal system. The nickel(II) ion is six-coordinated by N atoms from two AFT-ligands and four NH3 molecules. Its thermal properties are investigated by differential scanning calorimetry and thermogravimetry-derivative thermogravimetry methods, with the results demonstrating that the differential scanning calorimetry curve exhibits two endothermic and one exothermic processes. The endothermic processes are in the range of 130–510 °C with a peak temperature of 188 °C. The temperature from 230 to 400 °C is the exothermic process in which the peak temperature is 314.58 °C. In addition, Kissinger's and Ozawa-Doyle's methods are used for calculating the non-isothermal kinetics parameters. Moreover, the apparent activation energy (E), safety, and thermal stability parameters (T SADT, T TIT, T b) for Ni(NH3)4(AFT)2 are calculated. In addition, the calculated thermodynamic functions (∆S ≠, ∆H ≠, and ∆G ≠) for the exothermic decomposition process of Ni(NH3)4(AFT)2 are 55.07 J mol−1 K−1, 196.18 kJ mol−1, and 164.90 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] The E a and A of DNPDNAZ were 172.26kJ·mol−1 and 1013.15 s−1 respectively. [•] The Cp,m of DNPDNAZ was determined with a continuous Cp mode of micro-calorimeter and theoretical calculation. [•] It is reasonable for equation of GT − G 298.15K to added −(T −298.15) S 298.15K. [•] The calculated detonation velocity and pressure of DNPDNAZ are 7364.42m·s−1 and 23.75GPa, respectively. [•] DNPDNAZ and TNAZ are almost stable under light and the former is more sensitive than the latter. [ABSTRACT FROM AUTHOR]

• 1,3-Di(azido-acetoxy)-2-ethyl-2-nitropropane is synthesized by a new synthetic route. • The non-isothermal kinetic equation of the exothermic process for ENPEA is studied. • The gas products of thermal decomposition are N 2 , NO 2 , NH 3 , HCN, CO 2 , and CH 2 O. • The adiabatic time-to-explosion is approximately 18.2 s. 1,3-Di(azido-acetoxy)-2-ethyl-2-nitropropane (ENPEA) was synthesized from azidoacetic acid and 2-ethyl-2-nitro-1,3-propanediol. The thermal decomposition kinetics under pressures of 0.1 MPa and 3.0 MPa were investigated using differential scanning calorimetry (DSC). The thermal decomposition mechanism was studied by condensed-phase thermolysis/Fourier-transform infrared (FTIR) spectroscopy, simultaneous thermogravimetry (TG)-FTIR, and simultaneous TG-mass spectroscopy (MS) techniques. The activation energy under 3.0 MPa was found to be lower than that under 0.1 MPa. With increasing pressure, the decomposition heat increased significantly, while the peak temperature increased slightly. The non-isothermal kinetic equation of the exothermic process is d α /d T = 1012.5/ β × 4(1- α)3/4exp (−1.449 × 105/ RT) and the gas products are N 2 , NO 2 , NH 3 , HCN, CO 2 , and CH 2 O. Using the thermal decomposition parameters, the self-accelerating decomposition temperature and critical temperature of thermal explosion were calculated to be 191.4 °C and 204.4 °C, respectively. The specific heat capacity of ENPEA was studied by micro-DSC and the molar-heat capacity was found to be 570.9 J mol−1 K−1. Adiabatic time-to-explosion of ENPEA was calculated to be 18.2 s. These results are important in evaluating the thermal stability and application prospects of ENPEA. [ABSTRACT FROM AUTHOR]