Trinitrobenzene explosive power

Trinitrobenzene has three good qualities as an explosive high stability, great explosive power, and a low sensitiveness to impact and friction. There were good reasons for seeking more economic production methods. These investigations were particularly intensive during World War T. 

The Griesheim method is generally used for the laboratory preparation of sym-trinitrobenzene. However, it is too expensive to be applied in industry. Trinitrobenzene prepared in this way is much more costly than trinitrotoluene, whereas the gain in explosive power obtained is relatively small. 

Whether it is a -C-NO2, -O-NO2, or -N-NO2 link, all these structural features yield substances that are high explosives. Nitroglycerine, cyclonite, pentaerythrytol tetranitrate, tetryl, trinitrobenzene, trinitro-tolnene, and pentanitroaniline are examples of high explosives. The terms high explosives and low explosives are used for qualitative comparisons only. The explosive power of chemicals or their compositions is determined by their brisance and detonation velocity (see. Part A in Section IV). 

Trinitrobenzene (TNB) (2) is a more powerful explosive than TNT. However, the direct synthesis of TNB from benzene is not practical and the need for an indirect route for its synthesis makes its manufacture too expensive for use as a practical high explosive. 

Numerous aromatic nitramines have been synthesized but only A,2,4,6-tetranitro-A-methylaniline (tetryl) and l-(2-nitroxyethylnitramino)-2,4,6-trinitrobenzene (pentryl) have found practical use as explosives. Both tetryl and pentryl are more powerful than TNT. Tetryl is widely used in boosters and as a component of explosive formulations like tetrytol (tetryl/TNT), PTX-1 (tetryl/RDX/TNT) and Composition C-3 (tetryl/RDX/TNT/DNT/MNT/NC). 

Benzenetrifuroxan (66) is a powerful explosive which was first synthesised by Turek in 1931 by heating 1,3,5-triazido-2,4,6-trinitrobenzene (65) to its melting point (131 °C) the latter prepared from the reaction of 1,3,5-trichloro-2,4,6-trinitrobenzene with sodium azide in aqueous ethanol. 

Of the hydrocarbons toluene is the only one which nitrates sufficiently easily and yields a product which has the proper physical and explosive properties. Trinitrotoluene is the most widely used of the pure aromatic nitro compounds. It melts at such temperature that it can be loaded by pouring. It is easily and surely detonated, and is insensitive to shock, though not insensitive enough to penetrate armor-plate without exploding until afterwards. It is powerful and brisant, but less so than trinitrobenzene which would offer certain advantages if it could be procured in sufficient quantity. 

The product can be obtained by treating 2,4,6-trichloro- 1,3,5-trinitrobenzene with an alkali metal azide in alcoholic solution. It is a lead-free - initiating and powerful explosive and does not produce toxic fumes (- Lead-free Priming Compositions). The product undergoes a slow conversion into hexanitrosobenzene,... 

Even though 1,3,5-trinitrobenzene (TNB) has more shattering power (more hrisance) and is no more dangerous to handle, 2,4,6-trinitrotoluene (TNT) has always been the high explosive in more general use. Can you suggest a reason (connected with manufacture) for the popularity of TNT (Benzene and toluene are both readily available materials for many years benzene was cheaper.)... 

TRINITROBENZENE or 1,3,5-TRINITROBENZENE (99-35-4) A high explosive with more power than TNT and less sensitivity to impact. Sensitive to shock and heat. Incompatible with initiating explosives, combustible materials, oxidizers. Violent reaction with reducing agents. Forms heat-sensitive explosive complexes with alkyl or aryl metallates. 

The explosive force of the nitro derivatives of benzene and its homologues increases with the number of nitro groups and decreases with the number of methyl radicals. Symmetrical trinitrobenzene is a very powerful explosive but on account of the difficulty of introducing three nitro groups into the benzene ring it has been little used. Toluene can be nitrated more readily and the symmetrical trinitro derivative (387) was extensively used in the recent war it is called T.N.T. or, in Europe, trotyl or tolite. The trinitro derivative of metaxylene, C6H(CH3)2l,3,(N02)32,4,6, which was also used is... 

Trinitrobenzene is a high explosive, similar to trinitrotoluene. However, it is less sensitive to impact than the latter. Its brisance and power are higher than those of TNT. It detonates when heated rapidly. The dry material is highly sensitive to shock and heat. 

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