Preparation of Spherical Particles of 1,1-Diamino-2,2-dinitroethene (FOX-7) Using a Micellar Nanoreactor

Abstract

The need and preparation of spherical 1,1-diamino-2,2-dinitroethene (FOX-7) particles to meet certain special applications in high explosives and propellant formulation have been illustrated. Preparation of spherical FOX-7 particles by using a microemulsion technique has not been reported in the literature. In the present study, the preparation of spherical FOX-7 particles has been described using the novel concept of a micelle-based nanoreactor. Micelle-based nanoreactors have been prepared using a microemulsion of Triton X-100, cyclohexane, and water. Formation of spherical FOX-7 particles in the reverse micelle reactors have been described in the subsequent sections of this article. It is observed that spherical particles of FOX-7 are formed within 2 h in the microemulsion media. Analysis of the experimental results revealed that the particle size and shape of FOX-7 can be varied by changing the water/surfactant molar ratio in the microemulsion. Spherical particles synthesized by this method have diameters that are generally in the submicrometer to nanometer range. Impact sensitivity (h 50) of the spherical particles obtained by the fall-hammer method is around 45 cm compared to regular synthesized FOX-7 (i.e., 50 ± 5 cm) without any change in friction sensitivity, i.e. 36 kg. Loadability of the explosive charges can be enhanced by using these spherical particles of FOX-7.

Insight into the acidic group-induced nitration mechanism of 2-methyl-4,6-dihydroxypyrimidine (MDP) with nitronium

“…5,6 Such facts indicated that the activity free energy of the nitration should be considerably low, and the HSO 4 À -induced path A may be more favorable way than the direct path, which is in very good agreement with the experimental results. 6 Additionally, in view of the fact that a higher H 2 SO 4 concentration may benet an easier formation of NO 2 + along with a more difficult dissociation of H 2 SO 4 to form HSO 4 À , the concentration of H 2 SO 4 should be well controlled.…”

Compatibility Study of 1,1-Diamino-2,2-Dinitroethene (FOX-7) with Some Energetic Materials

“…Since it was reported in 1998 [2], it has quickly been the subject of explosives research in various countries of the world. Many researchers have focused on the theoretical calculation, synthesis, thermal properties, and nanostructure of FOX-7 [3][4][5][6][7][8][9][10]. Previous results on the physical and chemical characterization of FOX-7 have demonstrated that it possesses good thermal and chemical stability.…”

Preparation and Properties of Submicrometer‐Sized LLM‐105 via Spray‐Crystallization Method

“…It was reported that nanocrystals of energetic materials can not only decrease the mechanical sensitivity, but also help for improving the combustion and detonation properties as compared to coarse energetic materials [5][6][7][8]. Various techniques, such as electrospray crystallization, ultrasound-and spray-assisted crystallization, direct write ink-jet, microemulsion, rapid expansion of supercritical solutions, solvent-antisolvent crystallization, and sol-gel method, had been employed to fabricate nanocrystals of high explosives, including cyclotrimethylene trinitramine (RDX) [9], cyclotetramethylene tetranitramine (HMX) [10,11], hexanitrohexaazaisowurtzitane (CL-20) [12], 1,1-diamino-2,2-dinitroethylene (FOX-7) [13], 5-nitro-2,4-dihydro-3H-1,2,4-triazole-3-one (NTO) [14], 2,2',4,4'-,6,6'-hexanitrostilbene (HNS) [15], 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) [16,17], etc.…”