Hypergolic reactions

Hypergolic reaction systems have been proposed (Refs 46 73) for 5.56mm ammo, specifically triethylaluminum (TEA) together with inorganic oxidizers. This system is self-igniting in air, but is compatible with some nitrates, chlorates and perchlorates... 

Dutta, Some Observations on Hypergolic Reactions of UDMH and Furfuryl Alcohol with Fuming Nitric Acids , JArmamentStudies 14 (1), 62-65 (1978) CA 90,8520 (1978) [Reported is the relative ign delay on mixing UDMH with either red fuming, white fuming or 90% nitric acid. The ign delay decreased in the order 90% nitric acid WFNA to RFNA shortest]... 

Detonation Deflagration Thermal explosion Hypergolic reaction... 

SAFETY PROFILE Most carbonyls are highly toxic. The toxicity of carbonyls depends in part, but not always endrely, on their ready decomposition, which releases carbon monoxide. Symptoms are due in part to carbon monoxide and in part to the direct irritating action of the carbonyl. See specific carbonyl in question. Many carbonyl metals ignite spontaneously in air, some with a delay period. Others are moderate fire and explosion hazards when exposed to heat or flame. Carbonyls of alkali metals are potentially explosive. Hypergolic reaction... 

Dangerous fire hazard when exposed to heat or flame can react with oxidizing materials. To fight fire, use alcohol foam, CO2, dry chemical. Reacts violently with 1,3-butadiene. Violent hypergolic reaction with concentrated nitric acid. When heated to decomposition it emits acrid smoke and fumes. See also ALDEHYDES. 

DOT CLASSIFICATION Forbidden SAFETY PROFILE A powerful oxidant which explodes above 140°C. Explosive reaction with boron. Hypergolic reaction with dimethyl hydrazine or other strong organic bases. Forms powerfully explosive mixtures with nitrogen containing organic compounds (e.g., 2-nitroaniline). Upon decomposition it emits toxic fumes of NOx. See also NITRO COMPOUNDS. 

Ignition on contact with carbon + sulfinyl chloride (when ground), nitric acid (becomes violent), viton poly(l,l-difluorethylene-hexafluoropropylene), chlorine tri- and penta-fluorides (hypergolic reaction), diborane (forms a complex that is pyrophoric), hydrogen (above 300°C). 

Hypergolic reaction The immediate spontaneous ignition when two or more materials are mixed. 

The hypergolic reaction of sodium dicyanamide with nitric acid was followed to investigate the ignition and reaction mechanism (Litzinger Iyer, 2011). Gas phase products were analyzed by mass spectrometry, and the proposed balanced equation is ... 

Litzinger, T. Iyer, S. (2011). Hypergolic Reaction of Dicyanamide-Based Fuels with Nitric Acid, Energ. Euels, Vol. 25, No. 1, pp. 72-76, ISSN 0887-0624... 

---