Facile preparation and characterization of energetic hollow FOX-7/viton microspheres with improved thermal decomposition properties and reduced sensitivity

ABSTRACT

In this work, FOX-7 (1,1-diamino-2,2-dinitroethylene)-based polymeric microspheres were successfully prepared by the spray-drying method, in which recrystallized FOX-7 grains were integrated with Viton (dipolymers of hexafluoropropylene and vinylidene fluoride). FOX-7/Viton granules were prepared by water slurry method for comparison. FOX-7/Viton microspheres possessed a hollow structure with a typical shell thickness of 870 nm. The particle size of FOX-7/Viton grains on the shell of microspheres was significantly reduced from 33.31 μm (raw FOX-7) to 750 nm. Compared with raw FOX-7 and FOX-7/Viton granules prepared by the water slurry method, FOX-7/Viton hollow microspheres possessed a lower value of apparent activation energy in the thermal decomposition process and a higher characteristic height (H₅₀), which indicates increased thermal decomposition rate and better safety performance. VST test showed that three samples had acceptable thermal stability.

KEYWORDS:

• 1,1-diamino-2
• 2-dinitroethylene (FOX-7)
• polymer-bonded explosives (PBXs)
• hollow microspheres
• water slurry method
• spray-drying method

Acknowledgments

This research was supported by the Scientific and Technological Innovation Programs of Higher Education in Shanxi Province of China (Grant No. 2019L0524). The authors would like to thank Tingting Fan from Shiyanjia Lab (www.shiyanjia.com) for the XPS test.

Declaration of Interest Statement

No potential competing interest was reported by the authors.

Supplementary Material

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Additional information

Funding

This work was supported by the Scientific and Technological Innovation Programs of Higher Education in Shanxi Province of China [Grant No. 2019L0524].