An Analysis of the Pressure Dependence of Nitrate Ester Thermal Decomposition

1978 ◽  
Author(s):  
George F. Adams
Keyword(s):  
Thermal Decomposition ◽  
Pressure Dependence ◽  
Nitrate Ester

Identifying Thermal Decomposition Products of Nitrate Ester Explosives Using Gas Chromatography–Vacuum Ultraviolet Spectroscopy: An Experimental and Computational Study

2020 ◽  
Vol 74 (12) ◽  
pp. 1486-1495 ◽  
Author(s):  
Courtney A. Cruse ◽  
Jingzhi Pu ◽  
John V. Goodpaster
Keyword(s):  
Thermal Decomposition ◽  
Gas Chromatography ◽  
Density Functional ◽  
Vacuum Ultraviolet ◽  
Computational Study ◽  
Ultraviolet Spectroscopy ◽  
Decomposition Products ◽  
Nitrate Ester ◽  
Vacuum Ultraviolet Spectroscopy ◽  
Synchrotron Spectroscopy

Analysis of nitrate ester explosives (e.g., nitroglycerine) using gas chromatography–vacuum ultraviolet spectroscopy (GC–VUV) results in their thermal decomposition into nitric oxide, water, carbon monoxide, oxygen, and formaldehyde. These decomposition products exhibit highly structured spectra in the VUV that is not seen in larger molecules. Computational analysis using time-dependent density functional theory (TDDFT) was utilized to investigate the excited states and vibronic transitions of these decomposition products. The experimental and computational results are compared with those in previous literature using synchrotron spectroscopy, electron energy loss spectroscopy (EELS), photoabsorption spectroscopy, and other computational excited state methods. It was determined that a benchtop GC–VUV detector gives comparable results to those previously reported, and TDDFT could predict vibronic spacing and model molecular orbital diagrams.

Studies on the Thermal Decomposition Kinetic of an Nitrate Ester

2012 ◽  
Vol 182-183 ◽  
pp. 1575-1580 ◽  
Author(s):  
Juan Wang ◽  
Da Bin Liu ◽  
Xin Li Zhou
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Decomposition Mechanism ◽  
Thermal Decomposition Mechanism ◽  
Decomposition Kinetic ◽  
Heating Rates ◽  
Exponential Factor ◽  
Nitrate Ester ◽  
Dynamic Function ◽  
Thermal Decomposition Kinetic

The certain nitrate ester explosive has been tested by TG at the heating rates of 10, 15, 20, 25K•min-1. Basing on the TG experiment results the thermal decomposition activation energy has been calculated by the methods of Ozawa, KAS and iteration. And the thermal decomposition mechanism function of the explosive with 38 kinds of dynamic function was deduced by the method of integration. The results show that the thermal decomposition mechanism of the nitrate ester is chemical reaction mechanism. The thermal decomposition kinetic parameters such as average activation energy Ea and pre-exponential factor A are 133.23×103 J•mol-1 and 3.191×107 s-1 respectively.

Pyrolysis of Trifluoroacetaldehyde

1973 ◽  
Vol 51 (14) ◽  
pp. 2292-2296 ◽  
Author(s):  
Michael T. H. Liu ◽  
Leon F. Loucks ◽  
Robert C. Michaelson
Keyword(s):  
Thermal Decomposition ◽  
High Pressure ◽  
Free Radicals ◽  
Rate Equation ◽  
Pressure Dependence ◽  
Inert Gas ◽  
Order Process ◽  
First Order ◽  
Pressure Region ◽  
High Pressure Region

The thermal decomposition of trifluoroacetaldehyde has been studied over the 460–520 °C temperature range, and at pressures from 4 to 400 mm Hg. The experimental rate equation in the high-pressure region is of the form: Rate = k[CF3CHO]3/2 where[Formula: see text]The results are consistent with a mechanism initiated by a first order process and terminated by a second order recombination of two CF3 free radicals. At lower pressures (40 mm Hg), the ratio of kinit/kterm is pressure dependent and the overall order increases. The effects of added inert gas confirm this pressure dependence.

Thermal Decomposition of N-Acyloxy-N-alkoxyamides - a New HERON Reaction

2010 ◽  
Vol 63 (12) ◽  
pp. 1717 ◽  
Author(s):  
Jennifer P. Johns ◽  
Arjan van Losenoord ◽  
Clément Mary ◽  
Pierre Garcia ◽  
Damian S. Pankhurst ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Substituent Effects ◽  
Intramolecular Rearrangement ◽  
Nitrate Ester ◽  
Solvent Cage ◽  
Amide Resonance

The HERON reaction has been observed in the thermal decompositions of N-acyloxy-N-alkoxyamides 1b, members of the class of anomeric amides. The N,N-bisoxo-substitution results in reduced amide resonance and this, combined with an nO–σ*NOAcyl anomeric destabilization of the N–OAcyl bond, results in their intramolecular rearrangement to anhydrides 42 and alkoxynitrenes 43 in competition with homolysis of the N–OAcyl bond to alkoxyamidyls 51. The primary HERON product alkoxynitrenes are scavenged by oxygen, giving a nitrate ester, in competition with a rearrangement to nitriles and dimerization to hyponitrites, leading, under the conditions, to alcohols and aldehydes. Persistent alkoxyamidyls most likely form a 1,3-diradical in a solvent-cage reaction, which cyclizes to 3,5-disubstituted-(5H)-1,4,2-dioxazoles 47. Substituent effects support this competition reaction.

Characteristics of NEPE Propellant with Ammonium Dinitramide (ADN)

2011 ◽  
Vol 399-401 ◽  
pp. 279-283
Author(s):  
Wei Qiang Pang ◽  
Hui Xiang Xu ◽  
Yang Li ◽  
Xiao Bing Shi
Keyword(s):  
Thermal Decomposition ◽  
Specific Impulse ◽  
Flame Temperature ◽  
Minimum Free Energy ◽  
Ammonium Dinitramide ◽  
Mechanical Sensitivity ◽  
Nitrate Ester ◽  
Nickel Chromium ◽  
Wire Method ◽  
Nepe Propellant

The theoretical performances of NEPE (nitrate ester plasticized polyether) propellant with and without ADN were calculated with minimum free energy method. The burning characteristics and the thermal decomposition of propellants were determined by nickel chromium wire method and TG- DTG, respectively. The SEM of NEPE propellants and the mechanical sensitivity were also detected. The results show that the specific impulse and the adiabatic flame temperature are increase with an increase in the content of ADN oxidizer. The burning rate and pressure exponent of propellant with a change of pat content of ADN can be boosted higher than those of the AP formulations.

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
Keyword(s):  
Thermal Decomposition ◽  
Energetic Materials ◽  
Functional Group ◽  
The Other ◽  
Nitrate Ester ◽  
Ir Studies ◽  
Rapid Scan ◽  
Gas Products ◽  
Ft Ir ◽  
Ar Gas

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.

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