FOX-7

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 (FOA).^[4] According to other information it was synthesized in the USSR in 1990. 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

Names
Preferred IUPAC name 2,2-Dinitroethene-1,1-diamine
Other names FOX-7 FOX7
Identifiers
CAS Number	145250-81-3 Y
3D model (JSmol)	Interactive image
ChemSpider	467536
ECHA InfoCard	100.130.630
EC Number	604-466-1
PubChem CID	536770
UNII	3B2KYV7C3F
CompTox Dashboard (EPA)	DTXSID70894014
InChI InChI=1S/C2H4N4O4/c3-1(4)2(5(7)8)6(9)10/h3-4H2 Key: FUHQFAMVYDIUKL-UHFFFAOYSA-N
SMILES N/C(N)=C([N+]([O-])=O)\[N+]([O-])=O
Properties
Chemical formula	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)
Solubility in water	Soluble in polar aprotic solvents such as dimethyl sulfoxide (DMSO), N,N-Dimethylformamide (DMF), and N-Methyl-2-pyrrolidone (NMP)[1]
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H201, H228, H302
Precautionary statements	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). Y verify (what is YN ?) Infobox references

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]}