High performance and heat-resistant pyrazole-1,2,4-triazole energetic materials: Tuning the thermal stability by asymmetric framework and azo-bistriazole bridge

AbstractOwing to its simple preparation and high oxygen content, nitroformate [−C(NO2)3, NF] is an extremely attractive oxidant component for propellants and explosives. However, the poor thermostability of NF-based derivatives has been an unconquerable barrier for more than 150 years, thus hindering its application. In this study, the first example of a nitrogen-rich hydrogen-bonded organic framework (HOF-NF) is designed and constructed through self-assembly in energetic materials, in which NF anions are trapped in pores of the resulting framework via the dual force of ionic and hydrogen bonds from the strengthened framework. These factors lead to the decomposition temperature of the resulting HOF-NF moiety being 200 °C, which exceeds the challenge of thermal stability over 180 °C for the first time among NF-based compounds. A large number of NF-based compounds with high stabilities and excellent properties can be designed and synthesized on the basis of this work.

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Comparative thermal research on tetraazapentalene-derived heat-resistant energetic structures

Scientific Reports ◽

10.1038/s41598-020-78980-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jing Zhou ◽

Li Ding ◽

Yong Zhu ◽

Bozhou Wang ◽

Xiangzhi Li ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Decomposition ◽

Fourier Transform ◽

Energetic Materials ◽

Great Influence ◽

Fourier Transform Infrared ◽

Thermal Decomposition Mechanism ◽

Scanning Calorimetry ◽

In Situ Ftir Spectroscopy ◽

Heat Resistant

AbstractOrganic inner salt structures are ideal backbones for heat-resistant energetic materials and systematic studies towards the thermal properties of energetic organic inner salt structures are crucial to their applications. Herein, we report a comparative thermal research of two energetic organic inner salts with different tetraazapentalene backbones. Detailed thermal decomposition behaviors and kinetics were investigated through differential scanning calorimetry and thermogravimetric analysis (DSC-TG) methods, showing that the thermal stability of the inner salts is higher than most of the traditional heat-resistant energetic materials. Further studies towards the thermal decomposition mechanism were carried out through condensed-phase thermolysis/Fourier-transform infrared (in-situ FTIR) spectroscopy and the combination of differential scanning calorimetry-thermogravimetry-mass spectrometry-Fourier-transform infrared spectroscopy (DSC-TG-MS-FTIR) techniques. The experiment and calculation results prove that the arrangement of the inner salt backbones has great influence on the thermal decompositions of the corresponding energetic materials. The weak N4-N5 bond in “y-” pattern tetraazapentalene backbone lead to early decomposition process and the “z-” pattern tetraazapentalene backbone exhibits more concentrated decomposition behaviors.

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