Synthesis, crystal structure and thermodynamic properties of 3-(3,5-dimethylpyrazol-1-yl)-6-(benzylmethylene) hydrazone-s-tetrazine

Kou

et al. 2018

J. Chem. Eng. Data

2HNIW·HMX co-crystals are crystals composed of HNIW (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexazisowurtzitane) and HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane), and the HNIW molecule and HMX molecule are combined with noncovalent bonds in a lattice at a 2:1 ratio. The 2HNIW·HMX co-crystals are successfully synthesized by Bolton’s method and characterized by powder X-ray diffraction, laser Raman spectrometer, differential scanning calorimeter (DSC), and high performance liquid chromatograph. The standard enthalpy of formation of 2HNIW·HMX co-crystals is obtained as 861.9 ± 18.6 kJ·mol–1 under the direction of a designed thermochemical cycle with a Calvet microcalorimeter. The thermal decomposition behavior of 2HNIW·HMX co-crystals was studied under the non-isothermal condition with DSC. The apparent activation energy (E) of the decomposition is 332.23 kJ·mol–1 by Kissinger method, 324.10 kJ·mol–1 by Ozawa method, 314.06 ± 4.26 kJ·mol–1 by Friedman–Reich–Levi method, and 306.81 ± 3.12 kJ·mol–1 by NL-INT-SY3 method, respectively. The pre-exponential factor (logA/s–1) is 29.33 ± 0.33 via compensation effect. A continuous C p mode of Micro-DSC III was used to determine the specific heat capacity (C p,m) of the target co-crystals from 283.15 to 333.15 K, and the C p,m is 1114.04 ± 10.92 J·mol–1·K–1 at 298.15 K. These results could provide valuable information on 2HNIW·HMX co-crystals for both theory and application.

supporting

confidence: 75%

Standard Enthalpy of Formation, Thermal Behavior, and Specific Heat Capacity of 2HNIW·HMX Co-crystals

Kou

et al. 2018

J. Chem. Eng. Data

“…Hence, the research and development of high energy and low sensitivity compounds has been the priority in the domain of EMs. The traditional strategies to resolve this conflict have depended on the synthesis of novel energetic compounds and the optimization of their polymorphs [21][22][23][24].…”

Section: Introductionmentioning

confidence: 99%

Preparation, Characterization and the Thermodynamic Properties of HNIW ⋅ TNT Cocrystal

Jia

Propellants Explo Pyrotec

Kou

et al. 2019

The cocrystal of 2,4,6,8,10,12‐hexanitrohexaazaisowurtzitane (HNIW) with 2,4,6‐trinitrotoluene (TNT) (in a 1 : 1 mole ratio) was prepared by a solvent /non‐solvent (acetonitrile/distilled water) method, and systematically characterized by several methods. The thermal decomposition kinetics of HNIW ⋅ TNT cocrystal were investigated using dynamic Differential Scanning Calorimetry (DSC), and the apparent activation energy (Ea ) was calculated by Kissinger‐Akahira‐Sunose (KAS), Flynn‐Wall‐Ozawa (FWO) and Starink methods. The standard molar enthalpy of formation (ΔnormalfHmθ ) of HNIW ⋅ TNT cocrystal was acquired by a DC08‐1 Calvet microcalorimeter with the help of a rational thermochemical cycle and was 324.45±0.15 kJ mol−1. A continuous Cp mode of Micro‐DSC III was used to determine the specific heat capacity (Cp,m) of HNIW ⋅ TNT cocrystal from T=(283.15–333.15) K, and the Cp,m was 673.62 J mol−1 K−1 at 298.15 K.

“…Many efforts have been made to improve the power and insensitivity of EMs, and synthesis of new compounds and modification of existing materials are the primary methods used. 7–9 Co-crystallization is an effective and convenient means to improve the performance of materials, and it has drawn wide attention among researchers. 10,11 Co-crystallization, combining two or more neutral molecules through non-covalent interactions, could compromise the merits of the individual substance, and one of the energetic compounds has shown the ability to alter undesirable material properties, such as high sensitivity or low density.…”

Section: Introductionmentioning

confidence: 99%

Nonisothermal decomposition and safety parameters of HNIW/TNT cocrystal

Jia

et al. 2018

RSC Adv.