Ethanol, 2,2'-oxybis-,1,1'-dinitrate (693-21-0)

 Diethylene glycol dinitrate (693-21-0) is a nitrated alcohol ester produced by the action of concentrated nitric acid, normally admixed with an excess of strong sulfuric acid as a dehydrating agent, upon diethylene glycol.It is a colorless, odorless, viscous, oily liquid, specific gravity 1.4092 at 0 °C and 1.3846 at 20 °C ;  freezing point -11.5 °C under a standard atmosphere, the theoretical boiling point of approximately 197 °C difficult to confirm as the compound begins to decompose and spontaneously inflames at or slightly below this temperature. Partial pressure is reported as 0.007 mmHg (930 mPa) at 22.4 °C and 760 mmHg (101 kPa). It is readly miscible in most non-polar solvents, methanol, and cold acetic acid. Solubility in water (4.1 gm/L at 24 °C) and ethanol is very low. While chemically similar to a number of powerful high explosives, pure diethylene glycol dinitrate is extremely hard to initiate and will not propagate a detonation wave. It inflames only with difficulty (requiring localized heating to decomposition point) unless first atomized, and burns placidly even in quantity.Mixed with nitrocellulose and extruded under pressure, diethylene glycol dinitrate forms a tough colloid whose characteristics (good specific impulse, moderate burn rate and temperature, great resistance to accidental ignition and casual handling) make it well suited as a solid propellant for rocketry. It was widely used in this capacity, by both sides, during World War II. It also found use as a "productive" desensitizer (one that contributes to the overall power of the explosion rather than having a neutral or negative effect) in nitroglycerine and nitroglycol based explosives such as dynamite and blasting gelatin. It is also used as plasticizer for energetic amterials.If ingested, it, like nitroglycerine, produces rapid vasodialation through the release of nitrogen monoxide, NO, a physiological signaling molecule that acts to relax smooth muscle. As such it has occasionally been used medically to relieve angina, substernal chest pain associated with impaired cardiac circulation, since the concurrent headache it induces is somewhat less severe than other nitro compounds.At present, interest in the chemical seems to be mostly historical: more potent perchlorate/metal mixtures have long since supplanted it as a solid propellant ;  safer explosives have replaced nitroglycerine, true dynamites (the term is often used generically, even by experienced field technicians, to refer to almost any explosive supplied in small, discrete packages) retaining only a few specialist uses. The medical application was never widespread, the standard nitroglycerine being faster acting and almost literally dirt cheap ;  oral nitrates in any case being only palliative, not an effective treatment.

Reported in EPA TSCA Inventory. Glycol ether compounds are on the Community Right-To-Know List.