Solid-phase thermal decomposition of 2,4-dinitroimidazole (2,4-DNI)
- Sandia National Labs., Livermore, CA (United States). Combustion Research Facility
- Army ARDEC, Dover, NJ (United States). Energetic Materials Division
The solid-phase thermal decomposition of the insensitive energetic aromatic heterocycle 2,4-dinitroimidazole (2,4-DNI: mp 265--274 C) is studied utilizing simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) between 200 and 247 C. The pyrolysis products have been identified using perdeuterated and {sup 15}N-labeled isotopomers. The products consist of low molecular-weight gases and a thermally stable solid residue. The major gaseous products are NO, CO{sub 2}, CO, N{sub 2}, HNCO and H{sub 2}O. Minor gaseous products are HCN, C{sub 2}N{sub 2}, NO{sub 2}, C{sub 3}H{sub 4}N{sub 2}, C{sub 3}H{sub 3}N{sub 3}O and NH{sub 3}. The elemental formula of the residue is C{sub 2}HN{sub 2}O and FTIR analysis suggests that it is polyurea- and polycarbamate-like in nature. The rates of formation of the gaseous products and their respective quantities have been determined for a typical isothermal decomposition experiment at 235 C. The temporal behaviors of the gas formation rates indicate that the overall decomposition is characterized by a sequence of four events: (1) an early decomposition period induced by impurities and H{sub 2}O, (2) an induction period where CO{sub 2} and NO are the primary products formed at relatively constant rates, (3) an autoacceleratory period that peaks when the sample is depleted and (4) a final period in which the residue decomposes. Arrhenius parameters for the induction period are E{sub a} = 46.9 {+-} 0.7 kcal/mol and Log(A) = 16.3 {+-} 0.3. Decomposition pathways that are consistent with the data are presented.
- Research Organization:
- Sandia National Laboratory
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 248230
- Report Number(s):
- CONF-951155--; ISBN 1-55899-321-5
- Country of Publication:
- United States
- Language:
- English
Similar Records
Coupling experimental data and a prototype model to probe the physical and chemical processes of 2,4-dinitroimidazole solid-phase thermal decomposition
Shock initiation of 2,4-dinitroimidazole (2,4-DNI)
Related Subjects
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
ACTIVATION ENERGY
CARBON DIOXIDE
CARBON MONOXIDE
CHEMICAL EXPLOSIVES
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
EXPERIMENTAL DATA
IMIDAZOLES
ISOCYANATES
MASS SPECTROSCOPY
MELTING POINTS
NITRIC OXIDE
NITROGEN
PYROLYSIS
THERMAL GRAVIMETRIC ANALYSIS
WATER VAPOR