Showing papers in "Journal of Energetic Materials in 1984"
TL;DR: In this article, a review of the synthesis of energetic materials over the past 10-15 years is presented, with a focus on six different classes of compounds: polynitroaliphatics, dinitrofluoromethyl compounds, difluoramines, azido compounds and heterocyclic compounds.
Abstract: The synthesis of energetic materials over the past 10–15 years has been reviewed. The areas in which most activity has occurred embrace six different classes of compounds: polynitroaliphatics, dinitrofluoromethyl compounds, difluoramines, azido compounds, polynitroaromatics and heterocyclic compounds. Each class is treated within a single section covering the synthesis of the basic “building-block” materials, the strategies for transforming these into the final products and the scope and limitations of the reactions carried out. Most of the literature covered deals with new compounds but new or improved syntheses of compounds already known to possess useful properties are also described. Finally, developments in the prediction of explosive properties from molecular structure/composition are dealt with more briefly.
33 citations
TL;DR: In this article, the authors considered both bare and covered charges impacted by cylindrical steel projectiles using the Los Alamos 2DE code and found that 2DE predicted the critical velocity accurately, and checked ∫p2dt values along the initiation threshold.
Abstract: This paper concerns our numerical modeling of the projectile impact shock initiation of composition-B (comp-B). We have considered both bare and covered charges impacted by cylindrical steel projectiles using the Los Alamos 2DE code. We have examined the flow fields in some detail and compared predicted critical velocities with published experimental values. For bare charges, we observed two different mechanisms by which the critical velocity is determined. For impacts by projectiles of sufficiently large diameter initiation occurs as the impact induced shock wave builds to detonation by reinforcement due to burning behind the shock. For smaller diameter, high velocity projectiles, we saw that detonation or near detonation breaks out immediately on impact, but may be quenched by the ensuing rarefactions. We found that 2DE predicted the critical velocity accurately, We checked ∫p2dt values along the initiation threshold and found them to be relatively constant. We also simulated the special projec...
12 citations
TL;DR: In this article, the CJ pressures and detonation velocities for mono-and diamino-TNTs were calculated and it was shown that their performance would be better than that of -TNT.
Abstract: TNT molecule is significantly desensitized by substitution of ring hydrogens by -NH2 and -Cl functions. Calculated CJ pressures and detonation velocities for mono- and diamino-TNT show that their performance would be better than that of -TNT.
9 citations
TL;DR: In this paper, the authors examined the reaction profiles for the dissociation of HONO from 1-nitro-2-methyl-1-propene for two distinct reaction pathways.
Abstract: The reaction profiles for the dissociation of HONO from 1-nitro-2-methyl-1-propene have been examined for two distinct reaction pathways: a. The unimolecular dissociation of HONO from the intermediate CH2=C(CH3)CH=NOOH which in turn is formed by a unimolecular transfer of a hydrogen atom from the methyl group located cis to the nitro group in the parent molecule. b. The unimolecular dissociation of HONO from the intermediate formed by a bimolecular transfer of a hydrogen atom between two parent molecules. The overall activation enthalpies for the two processes are 62 and 50 kcal mol−1 respectively. The electronic nature of the transition states involved are discussed.
6 citations
TL;DR: In this paper, it is shown that various types of irradiation can induce NO2 loss, radical formation, or secondary amine production in TATB, and molecular orbital calculations are used to dispute the previously assigned structure of the radical in irradiated TATBs.
Abstract: TATB (1,3,5 triaminotrinitrobenzene) is a yellow compound that slowly changes to green upon exposure to sunlight. IR, UV-Visible, and ESCA data pertaining to this phenomenon are presented. It is shown that various types of irradiation can induce NO2 loss, radical formation, or secondary amine production in TATB. Molecular orbital calculations are used to dispute the previously assigned structure of the radical in irradiated TATB.
4 citations
TL;DR: An improved procedure was developed for preparing 1-(2-hydroxyethyl)-2,4,6-trinitrobenzene (I-A) from TNT and one mole of formaldehyde.
Abstract: An improved procedure was developed for preparing 1-(2-hydroxyethyl)-2,4,6-trinitrobenzene (I-A) from TNT and one mole of formaldehyde. The trinitro derivatives of ethylbenzene, 1,3-xylene, and mesitylene react similarly. Two of the compounds can also react with more than one mole of formaldehyde. Five related compounds are unreactive, probably because of steric hindrance. Several derivatives were prepared.
4 citations
Abstract: Surface structures of PETN and plastic bonded PETN were studied by high resolution X-Ray Photoelectron Spectroscopy (XPS) and Ion Scattering Spectroscopy (ISS). The coating material is a copolymer of vinyl chloride and chlorotrifluoroethylene. Specimen with 4 wt. Z coating material on PETN were used in these studies. High resolution elemented XPS spectra of F ls, N ls, C ls, and Cl 2p indicate that the surface of coated PETN (LX-16) show the surface layer to be thinner than 100A. 3He+ ISS data on LX-16 suggest that the coating on PETN is not uniform and is, in fact absent in some regions.
3 citations
TL;DR: A description of Lagrange gauge measurements in PBX-9404 and RX-26-AF is given in this paper, where the results are discussed along with the underlying theortetical assumptions.
Abstract: A description of Lagrange gauge measurements in PBX-9404 and RX-26-AF is given. The data are used to study the progress of reaction in these explosives. The results are discussed along with the underlying theortetical assumptions. Emphasis is given to the practical problems of constructing a description of the chemical reaction from gauge data.
3 citations
TL;DR: In this article, the x-ray diffraction of nitroguanidine chloride and nitruguanidine nitrate was used to solve the crystal structures of NO2 and (NH2)2CN.
Abstract: Crystal structures of nitroguanidine chloride and nitroguanidine nitrate were solved by x-ray diffraction. The nitroguanidine chloride crystal is triclinic, space group P1, with unit cell parameters: a = 6·656(8)A, b = 6·719(9) A, c = 6·816(8)A, α = 66·8(2)°, β = 75·4(2)°, γ = 84·5(2)°, DC = 1·7g cm−3, Z = 2. The nitroguanidine nitrate crystal is monoclinic, space group P21/c with unit cell parameters: a = 4·587(4)A, b = 6·377(6)A, c = 21·167(15)A, β = 94·7(1)°, DC = 1·8g cm−3, Z = 4. EPR spectra were detected from crystals of both compounds which had been exposed to gamma or x-radiation. The EPR spectra are assigned to NO2 and (NH2)2CN.
3 citations
TL;DR: In this article, the authors present predictive models for critical temperature of EAK systems, and the effects of admixture with aluminum and rust are discussed, as well as the effect of aluminum and steel admixture.
Abstract: EAK [mixtures of ethylenediamine dinitrate (EDD), ammonium nitrate (AN), and potassium nitrate (KN)] is a castable high explosive. Within the temperature range necessary for casting, there will always be a size and shape that will self-heat to explosion. Current predictive models for critical temperature of EAK systems are reported, and effects of admixture with aluminum and rust are discussed.
TL;DR: In this article, an experimental method involving the determination of the shock induced in PMMA by a test explosive is described which allows an assessment of the relative output performance of a booster composition in a geometry and size which could be reasonably expected to appear in a weapon design.
Abstract: An experimental method involving the determination of the shock induced in PMMA by a test explosive is described which allows an assessment of the relative output performance of a booster composition in a geometry and size which could be reasonably expected to appear in a weapon design. By applying the same analytical treatment of the experimental results to data generated by the 2-D Eulerian Hydrodynamic Code, HULL, estimates of the detonation pressure and the adiabatic exponent, γ, are obtained. The results indicate that the ordering of performance determined experimentally by this method agrees well with that deduced from velocity of detonation data using a simple γ-law equation of state and with a subsequent experimental verification where the run distance to detonation in a main charge explosive is observed when the booster is separated from the acceptor by a standard attenuator. Further, it is deduced that in the geometry considered using the initiation system described, the booster charges...