Explosives PETN = pentaerythritol tetranitrate

An interesting class of molecular crystals are those that easily decompose exothermally i.e., explosive crystals. Some form from small molecules such as lead azide [Pb(N3)2] and ammonium perchlorate (NH4CIO4) and others form moderately large molecules such as RDX (cyclotrimethylenetrinitramine), and PETN (pentaerythritol-tetranitrate). 

Between World War I and II, TNT replaced picric acid as the explosive of choice in munitions. It was also mixed with other compounds to produce more powerful explosives with unique characteristics. Amatol is a mixture containing between 40% and 80% ammonium nitrate and TNT. Pentolite is a mixture of PETN (pentaerythritol tetranitrate) and TNT. Another common explosive mixture is RDX (cyclotrimethylenetrinitramine) and TNT. RDX is an abbreviation for Royal Demolition Explosive. 

PETN [pentaerythritol tetranitrate, C(CH20N02)4] is an extremely sensitive high explosive. When used as a booster explosive, a bursting charge, or a plastic demolition charge, it is desensitized by mixture with trinitrotoluene or by the addition of wax. 

PETN. Pentaerythritol tetranitrate (PETN), 6, is known as one of the most sensitive military high explosives. It has a great shattering effect. PETN is not used in its pure form because of its high sensitivity to friction and impact [4, 6, 7]. 

PETN (pentaerythritol tetranitrate), 6, is an old explosive made from acetaldehyde and formaldehyde that reacts by condensation under basic... 

The commercially important explosive pentaerythritol tetranitrate [78-11-5] (PETN), C HgN40 2>... 

Pentaerythritol may be nitrated by a batch process at 15.25°C using concentrated nitric acid in a stainless steel vessel equipped with an agitator and cooling coils to keep the reaction temperature at 15—25°C. The PETN is precipitated in a jacketed diluter by adding sufficient water to the solution to reduce the acid concentration to about 30%. The crystals are vacuum filtered and washed with water followed by washes with water containing a small amount of sodium carbonate and then cold water. The water-wet PETN is dissolved in acetone containing a small amount of sodium carbonate at 50°C and reprecipitated with water the yield is about 95%. Impurities include pentaerythritol trinitrate, dipentaerythritol hexanitrate, and tripentaerythritol acetonitrate. Pentaerythritol tetranitrate is shipped wet in water—alcohol in packing similar to that used for primary explosives. 

Pentaerythritol tetranitrate is a high energy explosive that is used as a pressed base charge in blasting caps and detonators, as the core explosive in commercial detonating cord, and as the main explosive ingredient in sheet explosives. It is also mixed in various proportions with TNT to form the less sensitive pentoHtes, eg, PETN 50/TNT 50. PETN is easily initiated, its responses are reproducible, and it is readily available (144—146). 

Pentaerythritol tetranitrate (PETN) is a colorless crystalline solid that is very sensitive to initiation by a primary explosive. It is a powerful secondary explosive that has a great shattering effect. It is used in commercial blasting caps, detonation cords, and boosters. PETN is not used in its pure form because it is too sensitive to friction and impact. It is usually mixed with plasticized nitrocellulose or with synthetic rubbers to form PBXs. The most common form of explosive composition containing PETN is Pentolite, a mixture of 20 to 50% PETN and TNT. PETN can be incorporated into gelatinous industrial explosives. The military has in most cases replaced PETN with RDX because RDX is more thermally stable and has a longer shelf life. PETN is insoluble in water, sparingly soluble in alcohol, ether, and benzene, and soluble in acetone and methyl acetate. 

Investigated explosives included 2,4,6-trinitrotoluene (TNT), 2,4,6,N-tetranitro-N-methylaniline (tetryl), l,3,5-trinitro-l,3,5-triazacyclohexane (RDX), 1,3,5,7-tetranitro-l,3,5,7-tetrazacyclooctane (HMX) and pentaerythritol tetranitrate (PETN). The temperature of the injector, cooled with liquid CO2, was —5°C for 0.3 min, programmed from —5 to 250° C, at a rate of 200°C/min, with a final hold time of 8.4 min. The column temperature was 80° C for 2 min, programmed to 250° C at 25°C/min, with a final hold of 2 min. Electron ionization (El) in the positive-ion mode was used. Figure 4 shows the mass chromatograms of a mixture of explosives (lOppb each), extracted from water by Hquid—liquid extraction and X 100 concentration. Identification was based on typical fragment ions for each one of the explosives. 

Pentaerythritol tetranitrate (PETN) (3) is a powerful explosive which exhibits considerable brisance on detonation (VOD 8310 m/s at = 1.77 g/cm ). It is the most stable and least reactive of the common nitrate ester explosives. The relatively high sensitivity of PETN to friction and impact means that it is usually desensitized with phlegmatizers like wax and the product is used in detonation cord, boosters and as a base charge in detonators. Pentaerythritol tetranitrate can be mixed with synthetic polymers to form plastic bonded explosives (PBXs) like detasheet and Semtex-IA. A cast mixture of PETN and TNT in equal proportions is known as pentolite and has seen wide use as a military explosive and in booster charges. The physical, chemical and explosive properties of PETN commend its use as a high explosive. 

The condensation of acetaldehyde with excess formaldehyde in the presence of aqueous calcium hydroxide yields pentaerythritol (62) esterification of the latter with absolute nitric acid yields the powerful explosive, pentaerythritol tetranitrate (PETN) (3). ... 

Pentaerythritol tetranitrate (PETN) is a powerful high explosive with importance for both commercial and military applications. It is therefore unsurprising that work has been focused... 

Pentaerythritol Tetranitrate, abbrd as PETN), C(CH2 0N02)4- Its prepn, props, uses and analysis are described by Belgrano (Ref 31, p 176—183) Its props given on p 181 of Ref 31 are as follows Density (max) 1.62, Explosion Temperature 195°, Flame Temperature on Explosion (Temperature Developed on Explosion)... 

Shoeiyaku. Pentaerythritol Tetranitrate (PETN), C(CH2ON02)4 mw 316.14, N 17.72% wh crysts, d 1.77, mp 141° Brisance by Plate Dent Test 129% TNT Explosion Temperature 225° (decomp in 5 secs) Impact Sensitivity BurMines-App, 2-kg Wt 17cm (vs 100+ for TNT) Power by Ballistic Mortar Test 145% TNT Rate of Detonation 8300m/sec (Ref 8, p 276). Pressed PETN was used in Army 7.7 12.7-mm Fuzeless Projectiles and 20-mm MG Projs. Also in Boosters. Its mixt with TNT is called Pentoriru (qv). PETN with 8.5% wax was used for loading 20-mm Shells. Its mixtures with RDX were used in 7.7 12.7-mm Projectiles. PETN was also used in Incendiary Mixtures (Ref 1, p 27 Ref 5, p 372)... 

Pentaerythritol tetranitrate (PETN) Sensitive and powerful high explosive used in detonators... 

After World War I, major research programmes were inaugurated to find new and more powerful explosive materials. From these programmes came cyclotrimethylenetrinitramine [(RDX) (C3H6N606)] also called Cyclonite or Hexogen, and pentaerythritol tetranitrate [(PETN) (C5H8N4012)]. 

To produce explosive derivatives of pentaerythritol less sensitive than pentaerythritol tetranitrate, which could be applied for desensitizing PETN and lowering its melting point, so as to make it possible to fill shells with a molten explosive mixture containing penthrite. 

Secondary explosives, or high explosives, are generally less sensitive to heat and shock than primary explosives and are therefore safer to manufacture, transport, and handle. Most secondary explosives will simply burn rather than explode when ignited in air, and most can be detonated only by the nearby explosion of a primary initiator. Among the most common secondary explosives are nitroglycerin, trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and RDX. 

A variety of solvents, monomers, medicines, perfumes, and explosives are made from esters of nitric acid. Ethyl acetate, //-butyl acetate, iso-butyl acetate, glycerol trinitrate, pentaerythritol tetranitrate (PETN), glycol dinitrate, and cellulose nitrate are examples of such reactions. 

Application of Eq. 19 to the /7-HMX isotherm from simulations leads to the Us-Up curve shown in Fig. 11, where negative curvature in the simulation results is clearly evident (filled circles). While such behavior would be anomalous for metals, it is actually expected for pressures below about one GPa in the case of polyatomic molecular crystals, due to complicated molecular packings and intramolecular flexibility, and has in fact been reported for the high explosives pentaerythritol tetranitrate (PETN) where careful studies were performed for low levels of compression [77], By contrast, the experimental results for /3-HMX in the Us-Up plane do not exhibit significant curvature due to lack of data at pressures below about one Gpa [78], Thus, estimates of isothermal sound speeds, and hence isothermal bulk moduli, based on... 

Nitrogen-explosive compounds usually analysed by CL may be classified under three structural categories (i) nitroaromatic compounds, (ii) nitrate esters and (iii) nitramines. Examples of nitro-substituted hydrocarbons are nitromethane, trinitrobenzene (TNB), trinitrotoluene (TNT) and pentantiroaniline. Nitroglycerine (NG), ethylene glycol dinitrate (EGDN) and pentaerythritol tetranitrate (PETN) are nitrate esters [5], The nitro-explosive compounds that are the result of the presence of nitro and nitrate groups can... 

Fig. 5. Solvating gas chromatography (SGC) separation of a standard explosive mixture. Injected amounts 0.33 pg nitroglycerine (NG), 3.3 pg all others. Peaks (1) nitroglycerine, (2) 2,6-dinitrotolene, (3) 2,4-dinitrotoluene, (4) 2,4,6-trinitrotoluene, (5) pentaerythritol tetranitrate (PETN). Reprinted from Bowerbank et al. [48], Copyright (2000), with permission from Elsevier.

Fig. 13. (a) Alpha functions [alpha vs. E (Td)] of the explosives ions in pure air (top left) and a lOOOppm mixture of methylene chloride/air (top right) [57], (b) Differential mobility spectra of the explosives in purified air (bottom left) and lOOOppm of methylene chloride in air (bottom right). Explosives are from top 1,2,3-propanetriol trinitrate (NG) 1,3-dinitrobenzene (DNB) 2,6-dinitrotoluene (DNT) 2,4,6-trinitrotoluene (TNT) and pentaerythritol tetranitrate (PETN) [57]. 

First principles solid-state density functional analyses have also been performed on the explosive pentaerythritol tetranitrate (PETN) [42] to further understand the relationships between the choice of computational parameters and the predictions of molecular and solid-state properties, such as intermolecular interactions within the crystal cell, in the THz region. This study concluded that the Becke-Perdew functional has the best overall performance and that the choice of basis set is most critical. 

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