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| Names | |
|---|---|
| Preferred IUPAC name
2,2-Dinitroethene-1,1-diamine | |
| Other names
FOX-7
FOX7 | |
| Identifiers | |
3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.130.630 |
| EC Number |
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PubChem CID
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| C2H4N4O4 | |
| Molar mass | 148.08 |
| Appearance | Bright yellow crystalline powder[1] |
| Density | 1.885 g cm−3 |
| Melting point | 238 °C (460 °F; 511 K) (decomposes) |
| Soluble in polar aprotic solvents such as dimethyl sulfoxide (DMSO), N,N-Dimethylformamide (DMF), and N-Methyl-2-pyrrolidone (NMP)[1] | |
| Hazards | |
| GHS labelling: | |
  
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| Danger | |
| H201, H228, H302 | |
| P210, P230, P240, P241, P250, P264, P270, P280, P301+P312, P330, P370+P378, P370+P380, P372, P373, P401, P501 | |
| Explosive data | |
| Friction sensitivity | >350N[2] |
| Detonation velocity | 8870 m/s at density 1.885 g cm−3 (estimated) 8335 m/s at density 1.756 g cm−3 (measured, small-scale testing) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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FOX-7 or 1,1-diamino-2,2-dinitroethylene (DADNE)[3] is an insensitive high explosive compound. It was first synthesized in 1998 by the Swedish National Defence Research Institute (FOS).[4] The name FOX-7 is derived from the acronym of the Swedish Defence Research Agency (FOI), with the I replaced by an X to indicate an explosive, as in RDX and HMX.[5]
FOX-7 is similar to the insensitive chemical compound TATB, which is a benzene ring compound with three amino and three nitro groups.[6] FOX-7 has a two-carbon backbone rather than a benzene ring, but the amino and nitro groups have similar effects in both cases according to published reports on the sensitivity and chemical decay processes of FOX-7.[1] FOX-7 is stoichiometrically identical (but structurally unrelated)[2] to the explosives and propellants RDX and HMX, and therefore produces the same quantity of gas per gram, a key determinant of performance.[1]
By various measures, such as dropped-weight impact, friction force, temperature of ignition, and response to heating under confinement, it is less sensitive than the benchmark explosive RDX, while having performance slightly greater than the same.[2] Its explosive properties appear extremely favorable; in addition to its insensitive properties, the detonation velocity of mixtures of 80% FOX-7 plus binders is as high as Composition B, and nearly pure FOX-7 based plastic bonded explosives are slightly superior to RDX.[7] FOX-7 has been calculated to have a detonation velocity of 8,870 m/s.[8] Charges composed of EVA-coated FOX-7 granules pressed into pellets of 92% theoretical maximum density were found to have a detonation velocity of 7730 m/s, compared to 7630 m/s for a similar RDX/EVA composition, and 5% greater detonation pressure.[2]
FOX-7 is produced as of 2018 by EURENCO Bofors AB of Sweden,[9] having been made in batches up to 7kg in 2001.[10] In laboratory-scale synthesis, material costs were calculated at ~AU$3000/kg (prices in 2002 AUD) using prices from research chemical suppliers. At that time, FOX-7 could be purchased from NEXPLO Bofors AB at SEK3200/kg.[2] Due to its small-scale production, the cost of FOX-7 is relatively high. However, the production is based on commercial starting material and the synthesis is uncomplicated.[11]
FOX-7 is an attractive subject for research and development due to its combination of insensitivity and power. FOX-7 performs similarly to RDX, one of the most powerful explosives and propellants in use, unlike other insensitive high explosives under investigation, such as TATB, nitrotriazolone, TEX, and 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105). Due to the need for less sensitive munitions, FOX-7 is being investigated at many military research centers,[1] including in Australia, India, the USA, and Sweden.[5][2][9][10]