UDMH = Dimethylhydrazin

MMHa.nd UDMH. MonomethyUiydrazine and yyz -dimethylhydrazine are manufactured by Olin Corp. using the same Raschig process and equipment employed for anhydrous hydrazine. Chloramine, prepared as described above, reacts with methylamine or dimethylamine instead of with... 

Hydraziae is toxic and readily absorbed by oral, dermal, or inhalation routes of exposure. Contact with hydraziae irritates the skin, eyes, and respiratory tract. Liquid splashed iato the eyes may cause permanent damage to the cornea. At high doses it can cause convulsions, but even low doses may result ia ceatral aervous system depressioa. Death from acute exposure results from coavulsioas, respiratory arrest, and cardiovascular coUapse. Repeated exposure may affect the lungs, Hver, and kidneys. Of the hydraziae derivatives studied, 1,1-dimethylhydrazine (UDMH) appears to be the least hepatotoxic monomethyl-hydrazine (MMH) seems to be more toxic to the kidneys. Evidence is limited as to the effect of hydraziae oa reproductioa and/or development however, animal studies demonstrate that only doses that produce toxicity ia pregaant rats result ia embryotoxicity (164). 

The determination of organic compounds by their direct catalytic effect on indicator reaction rates is a relatively unexplored ai ea promising valuable analytical chai acteristics, as we have recently shown in the determination of traces of unsymmetrical dimethylhydrazine (UDMH) by the oxidation of 3,3, 5,5 -tetramethylbenzidine (TMB) by atmospheric oxygen initiated with persulfate [1]. 

Until recently the atmospheric chemistry of nitrogen-containing compounds such as the hydrazines, which are widely used as fuels in military and space vehicles, has received comparatively little attention. N,N-dimethyIhydrazine (also UDMH = unsymmetrical dimethylhydrazine) is used in liquid-fueled rockets, and thus there Is a possibility that its use, storage, and handling could result in its release in the atmosphere. 

Synonyms 1,1 -di methylhydrazine, unsymmetrical-di methylhydrazine, asymmetrical-di methylhydrazine UDMH, A A -di methyl hydrazi ne, Dimazine 1,2-di methylhydrazine, symmetrical dimethylhydrazine, SDMH, N, A -di methyl hydrazi ne Budavari et al. 1989... 

ATSDR (Agency for Toxic Substances and Disease Registry). 1994. Toxicological Profile for Hydrazine. Draft. U.S. Department of Health and Human Services, ATSDR, Atlanta, Ga. Back, K.C., M.K.Pinkerton, A.B.Cooper, and others. 1963. Absorption, distribution, and excretion of 1,1-dimethylhydrazine (UDMH). Toxicol. Appl. Pharmacol. 5 401—413. 

Haun, C.C. 1977. Canine hepatotoxic response to the inhalation of 1,1-dimethylhydrazine (UDMH) and 1,1-dimethylhydrazine with dimethylnitrosamine (DMNA). 

Synonyms BRN 0605261 CCRIS 258 Dimazine asjm-Dimethylhydrazine unsym-D me hy -hydrazine A, A -Dimethylhydrazine DMH EINECS 200-316-0 NSC 60517 RCRA waste number U098 UDMH UN 1163. 

Synonyms asym-Dimethylhydrazine un-symmetrical dimethylhydrazine dimazine UDMH... 

Of the many alkyl substituted hydrazines, only two are used as rocket fuels now monomethyl hydrazine (MMH), CH3NHNH2, and unsymmetrical dimethylhydrazine (UDMH), (CH3)2NNH2. (See Hypergolic Fuels in this Vol for combustion properties as rocket fuels). Their physical properties are summarized below... 

Intermixing of gelled N204 UDMH (unsym-dimethylhydrazine) results in a fire if large surface areas of gelled fuel oxidizer come in contact. The fire is similar to.that which occurs when two hypergolic proplnts are... 

DETA Diethylenetriamine, (NH2C2H4)2NH MMH Monomethylhydrazine, CH3N2H3 UDMH wnsym-Dimethylhydrazine, (CH3)2N2H2 50-50 Fuel blend 50% N2H4-50% UDMH... 

They remain liquid under normal, ambient operating conditions (moderate temperature, atmospheric pressure). Safety in storage and handling should also be considered. A storable liquid propellant should not have an excessively high vapour pressure at ambient temperature. The leading storable propellant uses dinitrogen tetroxide as oxidizer and a 50/50 mixture of hydrazine-unsymmetrical dimethylhydrazine (UDMH) as fuel [71], Nitrogen tetroxide and UDMH is another storable propellant mixture in use [73],... 

Chem. Abstr. Serv. Reg.No. 57-14-7 Chem. Abstr. Name 1,1-Dimethylhydrazine lUPAC Systematic Name 1,1 -DimethyIhydrazine Synonyms Dimazine dimazin UDMH... 

The most important compds are aniline and unsvm-dimethylhydrazine, abbr UDMH. Less important are methyl amine and diethylene-triamine)... 

UDMH (Unsymmetrica dimethylhydrazine, 1,1-Dimethylhydrazine or Dimazine). See in Vol 5, D1344-L to D1346-R in Vol 7, H203-R to H204-L and under Liquid Propellants in Table 3, L40 to L41. Addnl Refs on this compd and mixts contg it are listed next ... 

Dimethylhydrazine and derivs 5 D1344—D1346 sym-dimethylhydrazine 5 D1346 uns-dimethylhydrazine (UDMH)... 

Storable. Together with liquid hydrocarbons, hydrazine-type fuels are the most important storable liquid propellants. They include hydrazine (N2H4), MMH, unsymmetrical dimethylhydrazine (UDMH), Aerozine-50 (50% N2H4 and 50% UDMH), and various blends of these fuels with other amine-based components. All hydrazine-type fuels are toxic to some degree, as are their breakdown products in the environment (especially, as in the case of dilute UDMH with nitrates and nitrites, forming carcinogenic and highly water soluble nitrosodimethylamine, or NDMA). The most notable hydrocarbon storable fuels include kerosene-based liquid propellants (RP-1, JP-8, and others). 

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