Chemical explosives TATB

We have also reported a new explosive called, N,N -bis(l,2,4-triazol-3-yl)-4,4 -diamino-2,2, 3,3,5,5,6,6,-oclarnlroazobenzene (BTDAONAB) [Structure (2.39)], prepared on a laboratory scale and characterized for its thermal and explosive characteristics [25]. This explosive possesses a remarkable thermal stability which is better than the most thermally stable explosive, TATB and at the same time, its VOD is more than that of TATB. The chemical structures of some newly reported explosives are depicted in Figure 2.3. 

Properties of Chemical Explosives and Explosive Simulants , UCRL-51319, Rev 1, LL Lab, Livermore, Contract No W-7405-Eng48 (1974), pp 18-95 18-96 30) P.E. Karmer, TATB... 

Explosive decomposition of conventional EMs is based on chemical processes. In spite of this fact, very few authors in the past dealt with, and today are deahng with, the initiation mechanisms from the point-of-view of chemistry. As follows from Sect. 3, most authors of papers published in this field try to solve the problem of micro-initiation by means of quantum chemistry [1,3-5,39,56,60,74,81,85,105,106,109]. The simulations are predominantly restricted to a few selected molecules of energetic substances (NM, RDX, HMX and TATB are the dominating ones) and their crystals [1,3, 5,56,60,74], or in some cases only to hypothetical two-atom molecules [109]. 

McGuire, R.R. and Tarver, C.M. (1981) Chemical Decomposition Models for the Thermal Explosion of Confined HMX, TATB, RDX and TNT Explosives Proceedings of the 7th Symposium (International) on Detonation, US Naval Academy, Annapolis, MD, 56-64. 

ABSTRACT. We describe an apparatus by which the detonation products of an explosive can be identified and whose relative concentrations can be determined quantitatively. These measurements can be made on products that have been formed in less than one microsecond after the passage of the detonation wave. The technique is based on the rapid quenching of chemical reactions by virtue of the free expansion of the products into vacuum. Of course, products that have been formed over a longer period of time and under different pressure/temperature conditions can also be studied. Time resolved molecular-beam mass spectrometry is used, so that whether detonation occurred or not in forming the products can be determined. We describe optical techniques, principally Schlieren photographs, that also confirm detonation. We report measurements made on six standard explosives, PETN, RDX, HMX, HNS, TNT and TATB, and one research explosive, nitric oxide. For none of the standard explosives do we measure product distributions that agree with model predictions based on equilibrium assumptions. A computer model of the free expansion is described briefly and its importance to the interpretation of the data is emphasized. 

From the present results it can be said that mechanical harm inflicted on energetic materials manifests itself in hot spots as chemical and physical changes. The physical changes are perhaps dependent on the melting, subliming characteristics, crystal habit and other properties of the material. They show up as holes in TATB but stringed structure in TNT. The explosive in the vicinity of hot spots becomes chemically... 

Another interesting result of the Russian conductivity of explosives study was the measurement of electrical conductivity of TATB shocked to pressures too low to result in prompt detonation. The initial stage of the electrical conductivity growth in compressed explosive represents the conductivity of the crystalline explosive, which is compressed and heated by the shock wave but not reacted by the hot spots. The chemical reaction started by the hot spots releases energy that increases the electrical conductivity. The stages of the conductivity growth for a thin layer of TATB shocked to 173 kbars are shown in Figure 2.71. 

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