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

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. [ABSTRACT FROM AUTHOR]