Thermal Decomposition of Energetic Materials 33: The Thermolysis Pathway of the Azidodinitromethyl Group

1989 ◽  
Vol 43 (4) ◽  
pp. 650-653 ◽  
Author(s):  
J. T. Cronin ◽  
T. B. Brill

Rapid-scan FT-IR studies are reported for the thermal decomposition of R (CH2)3C(NO2)2N3 ( R = CH3OC(O)-, HO-, -OC(O)O-, and O2NO-) at a heating rate of 70°C/s or higher. The thermolysis is initiated by the -C(NO2)2N, group. At 15 psi Ar, a sharp exotherm occurs at about 180°C. Except when R = O2NO-, the gas products are NO2, N2 (inferred), and R(CH2)3CN, making the rapid thermal decomposition one of the most straightforward yet observed for an energetic functional group. At an Ar gas pressure of 500 psi, the products are altered only to the extent that partial oxidation of the organonitrile occurs. The exotherm remains at about 180°C but is greatly accentuated. When R = O2NO-, the thermolysis temperature profile is very similar to the other compounds, but an organonitrile is not detected. Instead, at 15 psi Ar, a mixture of gas products resulting from the reaction of NO, with the backbone is detected, indicating that the nitrate ester also reacts. At 500 psi Ar, the products and thermal profile of this compound are characteristic of an explosion.

1987 ◽  
Vol 41 (7) ◽  
pp. 1147-1151 ◽  
Author(s):  
J. T. Cronin ◽  
T. B. Brill

Rapid-scan infrared spectroscopy (RSFT-IR) with better than 100-ms temporal resolution has been used to quantify the gas decomposition products of energetic materials in real time at various heating rates up to 800°C/s and under buffer gas pressures of 1 to 1000 psi. A new method is described that permits simultaneous real-time recording of the temperature of the condensed phase and of the IR spectra of the gaseous products under the above conditions. Endothermic and exothermic events in the condensed phase can now be correlated with the evolved gases under conditions approaching those of combustion. The design and procedure for using the cell are given and are applied to the thermolysis of 1,7-diazido-2,4,6-trinitro-2,4,6-triazaheptane (DATH) and pentaery-thrityltetrammonium nitrate (PTTN).


1992 ◽  
Vol 46 (6) ◽  
pp. 900-911 ◽  
Author(s):  
T. B. Brill ◽  
P. J. Brush ◽  
K. J. James ◽  
J. E. Shepherd ◽  
K. J. Pfeiffer

The interface of a Pt filament pyrolysis control unit and a rapid-scan FT-IR spectrometer is described that enables the thermal decomposition of a thin film of material to be studied isothermally after heating at 2000°C/s. A model of the heat transfer of the Pt filament as a function of gas atmosphere and pressure is developed to help understand the instrument response. The control voltage of the Pt filament is highly sensitive to the thermochemistry of the thin film of sample. By simultaneously recording the control voltage and the rapid-scan IR spectra of the near-surface gas products, one learns considerable detail about chemical mechanisms relevant to combustion of a bulk material. The application of T-jump/FT-IR spectroscopy is illustrated with rapid thermolysis data for the energetic organoazide polymers azidomethyl-methyloxetane (AMMO), bis(azidomethyl)oxetane (BAMO), and glycidylazide polymer (GAP); the cyclic nitramine, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetraazacine (HMX); and the nitroaromatic 1,3,5-triamino-2,4,6-trinitrobenzene (TATB).


1992 ◽  
Vol 57 (11) ◽  
pp. 2302-2308
Author(s):  
Karel Mocek ◽  
Erich Lippert ◽  
Emerich Erdös

The kinetics of the reaction of solid sodium carbonate with sulfur dioxide depends on the microstructure of the solid, which in turn is affected by the way and conditions of its preparation. The active form, analogous to that obtained by thermal decomposition of NaHCO3, emerges from the dehydration of Na2CO3 . 10 H2O in a vacuum or its weathering in air at room temperature. The two active forms are porous and have approximately the same specific surface area. Partial hydration of the active Na2CO3 in air at room temperature followed by thermal dehydration does not bring about a significant decrease in reactivity. On the other hand, if the preparation of anhydrous Na2CO3 involves, partly or completely, the liquid phase, the reactivity of the product is substantially lower.


Fuel ◽  
2021 ◽  
Vol 296 ◽  
pp. 120669
Author(s):  
Wenlong Mo ◽  
Zifan Wu ◽  
Xiaoqiang He ◽  
Wenjie Qiang ◽  
Bo Wei ◽  
...  

Molbank ◽  
10.3390/m1238 ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. M1238
Author(s):  
Ion Burcă ◽  
Valentin Badea ◽  
Calin Deleanu ◽  
Vasile-Nicolae Bercean

A new azo compound was prepared via the azo coupling reaction between 4-(ethoxycarbonyl)-3-methyl-1H-pyrazole-5-diazonium chloride and 8-hydroxyquinoline (oxine). The ester functional group of the obtained compound was hydrolyzed and thus a new chemical structure with a carboxylic functional group resulted. The structures of the new compounds were fully characterized by: UV–Vis, FT-IR, 1D and 2D NMR spectroscopy, and HRMS spectrometry.


Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 165
Author(s):  
Sandip Madhukar Deshmukh ◽  
Mohaseen S. Tamboli ◽  
Hamid Shaikh ◽  
Santosh B. Babar ◽  
Dipak P. Hiwarale ◽  
...  

In the present work, we have reported a facile and large-scale synthesis of TiO2 nanoparticles (NPs) through urea-assisted thermal decomposition of titanium oxysulphate. We have successfully synthesized TiO2 NPs by using this effective route with different weight ratios of titanium oxysulphate: urea. The structures and properties of TiO2 NPs were confirmed by scanning electron microscope) (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FT-IR), ultra violet–visible spectroscopy (UV-vis), and photoluminescence (Pl) techniques. XRD demonstrated that TiO2 NPs holds of anatase crystal phase with crystallizing size 14–19 nm even after heating at 600 °C. TGA, SEM, and TEM images reveal urea’s role, which controls the size, morphology, and aggregation of TiO2 NPs during the thermal decomposition. These TiO2 NPs were employed for photodegradation of Methyl Orange (MO) in the presence of ultraviolet (UV) radiation. An interesting find was that the TiO2 NPs exhibited better photocatalytic activity and excellent recycling stability over several photodegradation cycles. Furthermore, the present method has a great perspective to be used as an efficient method for large-scale synthesis of TiO2 NPs.


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