Molecular absorption spectra of dinitramide and its salts

Thakre

Combust Explos Shock Waves

2005

A comprehensive review of thermal decomposition and combustion of ammonium dinitramide (ADN) has been conducted. The basic thermal properties, chemical pathways, and reaction products in both the condensed and gas phases are analyzed over a broad range of ambient conditions. Detailed combustion-wave structures and burning-rate characteristics are discussed. Prominent features of ADN combustion are identified and compared with other types of energetic materials. In particular, the influence of various condensed-and gas-phase processes in dictating the pressure and temperature sensitivities of the burning rate is examined. In the condensed phase, decomposition proceeds through the mechanisms ADN → NH 4 NO 3 + N 2 O and ADN → NH 3 + HNO 3 + N 2 O, the former mechanism being the basic one. In the gas phase, the mechanisms ADN → NH 3 + HDN and ADN → NH 3 + HNO 3 + N 2 O are prevalent. The gas-phase combustion-wave structure in the range of 5-20 atm consists of a near-surface primary flame followed by a dark-zone temperature plateau at 600-1000 • C and a secondary flame followed by another dark-zone temperature plateau at 1000-1400 • C. At higher pressures (60 atm and above), a final flame is observed at about 1800 • C without the existence of any dark-zone temperature plateau. ADN combustion is stable in the range of 5-20 atm and the pressure sensitivity of the burning rate has the form r b = 20.72p 0.604 [mm/sec] (p = 0.5-2.0 MPa). The burning characteristics are controlled by exothermic decomposition in the condensed phase. Above 100 atm, the burning rate is well correlated with pressure as r b = 8.50p 0.608 [mm/sec] (p = 10-36 MPa). Combustion is stable, and intensive heat feedback from the gas phase dictates the burning rate. The pressure dependence of the burning rate, however, becomes irregular in the range of 20-100 atm. This phenomenon may be attributed to the competing influence of the condensed-phase and gas-phase exothermic reactions in determining the propellant surface conditions and the associated burning rate.

Section: Introductionmentioning

confidence: 98%

Thermal Decomposition and Combustion of Ammonium Dinitramide (Review)

Thakre

Combust Explos Shock Waves

2005

“…Thus the free acid, NH(NO 2 ) 2 , should be called dinitraminic acid. The dinitramide ion is a uniquely stable oxy anion of nitrogen and its salts are high oxygen density groupings that have been prepared with many different counterions, − including the ammonium, lithium, potassium, and cesium salts which are the subject of this report.…”

Section: Introductionmentioning

confidence: 99%

A New Class of Flexible Energetic Salts: The Crystal Structures of the Ammonium, Lithium, Potassium, and Cesium Salts of Dinitramide

et al. 1997

The crystal structures of the ammonium, 1, lithium, 2, potassium, 3, and cesium, 4, salts of a new nitrogen oxy anion, N3O4 -, have been determined. In 1 there are two interpenetrating three-dimensional lattices linked by strong hydrogen-bonding interactions between all four ammonium protons and three of the four dinitramide oxygen atoms. Even though 2−4 have similar formula units each has a completely different structure characterized by differing coordination numbers and geometries. The structure of 2 is unique in that it is the only one containing a dinitramide ion in the C 2 conformation predicted by ab initio studies to be the minimum energy conformation. There is good agreement between the predicted and experimental metrical parameters for the C 2 conformer of the dinitramide anion.

“…Following the publication of our patents, Russian workers at the Zelinsky Institute in Moscow on the whole and at the LNPO Soyuz facility and at the Zelinsky Institute in Moscow presented accounts of their independent research on the synthesis and use of dinitraminic acid and dinitramide salts. ,,,,− …”

Section: Introduction and Backgroundmentioning

confidence: 99%

“…[15][16][17][18][19][20][21][22] Following the publication of our patents, Russian workers at the Zelinsky Institute in Moscow on the whole and at the LNPO Soyuz facility and at the Zelinsky Institute in Moscow presented accounts of their independent research on the synthesis and use of dinitraminic acid and dinitramide salts. 3,7,9,13, [23][24][25][26][27][28] The choice of names for dinitramide salts is based on an extension of the well-established nomenclature for nitramide. The free acid, HN(NO 2 ) 2 , should be named dinitraminic acid.…”

Section: Introductionmentioning

confidence: 99%

1,1,3,3-Tetraoxo-1,2,3-triazapropene Anion, a New Oxy Anion of Nitrogen: The Dinitramide Anion and Its Salts

1997

We report the synthesis of a completely new, stable class of inorganic salts named the dinitramide salts. These salts are based on a newly discovered nitrogen oxide anion known as the dinitramide anion. The dinitramide anion is a uniquely stable, high oxygen density grouping that can be prepared in many salt combinations including the ammonium or hydrazinium salts. The dinitramide anion has both fundamental scientific interest and practical applications. We describe here the synthesis of dinitramide salts and give a preliminary report on their properties.