Diethylene glycol dinitrate is a nitratedalcoholester produced by the action of concentrated nitric acid, normally admixed with an excess of strong sulfuric acid as a dehydrating agent, upon diethylene glycol. Diethylene glycol dinitrate is a colorless, odorless, viscous, oily liquid, with 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 at 22.4 °C and. It is readily miscible in most non-polar solvents, methanol, and cold acetic acid. Solubility in water 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 unless first atomized, and burns placidly even in quantity. Mixed with nitrocellulose and extrudedunder pressure, diethylene glycol dinitrate forms a tough colloid whose characteristics make it well suited as a smokeless powder for artillery and a solid propellant for rocketry. It was widely used in this capacity during World War II. It also found use as a "productive" desensitizer in nitroglycerine and nitroglycol-based explosives such as dynamite and blasting gelatin. It is also used as plasticizer for energetic materials. If ingested, like nitroglycerine, it produces rapidvasodilation through the release of nitrogen monoxide, NO. Popularly termed nitric oxide, NO is a physiological signaling molecule that relaxes smooth muscle. Consequently, diethylene glycol dinitrate has occasionally been used medically to relieve angina, substernal chest pain associated with impaired cardiac circulation. The rationale is that 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 retaining only a few specialist uses. The medical application was never widespread, the standard nitroglycerine being faster acting and very inexpensive; oral nitrates in any case being only palliative, not an effective treatment. Triethylene glycol dinitrate, diethylene glycol dinitrate, and trimethylolethane trinitrate are being considered as replacements for nitroglycerin in propellants.
