Replacement of Toxic Hydrazines in Satellite Propulsion with Greener Dinitramide-Based Energetic Ionic Liquid Candidates.

Satellite propulsion uses liquid mono or bi-propellants composed of a hydrazine in combination with a strong oxidant. However, hydrazines are highly toxic. As a result, many research efforts for more environmentally compatible propellants have been made over the past decade.

(E)-1,1,4,4-Tetramethyl-2-tetrazene (TMTZ): A Prospective Alternative to Hydrazines in Rocket Propulsion.

1,1,4,4-Tetramethyl-2-tetrazene (TMTZ) is considered as a prospective replacement for toxic hydrazines used in liquid rocket propulsion. The heat of formation of TMTZ was computed and measured, giving values well above those of the hydrazines commonly used in propulsion. This led to a predicted maximum I of 337 s for TMTZ/N O mixtures, which is a value comparable to that of monomethylhydrazine.

Energetic 2,2-Dimethyltriazanium Salts: A New Family of Nitrogen-Rich Hydrazine Derivatives.

Amination of 1,1-dimethylhydrazine with NH2 Cl or hydroxylamine-O-sulfonic acid yields 2,2-dimethyltriazanium (DMTZ) chloride (3) and sulphate (4), respectively. The DMTZ cation was paired with the nitrogen-rich anions 5-aminotetrazolate (5), 5-nitrotetrazolate (6), 5,5'-azobistetrazolate (7), and azide (8), yielding a new family of energetic salts. The synthesis was carried out by metathesis reactions of salts 3 or 4 and a suitable silver or barium salt.

Synthesis and characterization of two formyl 2-tetrazenes.

The synthesis of two formyl 2-tetrazenes, namely, (E)-1-formyl-1,4,4-trimethyl-2-tetrazene (2) and (E)-1,4-diformyl-1,4-dimethyl-2-tetrazene (3), by oxidation of (E)-1,1,4,4-tetramethyl-2-tetrazene (1) using potassium permanganate in acetone solution is presented. Compound 3 was also synthesized in an improved yield from the oxidation of 1-formyl-1-methylhydrazine (4a) using potassium permanganate in acetone. Both compounds 2 and 3 were characterized by analytical (elemental analysis, GC-MS) and spectroscopic methods ((1)H, (13)C, and (15)N NMR spectroscopy, and IR and Raman spectroscopy).