Mixtures phlegmatization

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 majority of Sprengel s fuels were energetic hydrocarbons. Chlorate-based composite explosives tend to be very sensitive to friction and shock. When mixed with energetic fuels, the chlorate formulations are even more sensitive. To address this problem, historically two paths were taken. The chlorate was either mixed with a nonenergetic hydrocarbon or the mixture was phlegmatized (lubricated) if an energetic fuel was desired. 

BB1 gives instructions on how to prepare a chlorate-based mixture that is quite prevalent in the anarchist literature. This formulation consists of KCIO3 phlegmatized with Vaseline. Typically this particular formulation is given the nickname Poor Man s C-4. It does not have the power of C-4 but does posses... 

Explosive Mixtures and Phlegmatized Explosives, Physical Methods for Analyzing the Components of. Discussed in refs Refs l)Author, MP 36, 133-62 (1954) 2)... 

Dinitronaphthalene) 20%, which may he considered as phlegmatized PA (Refs 1, 3, 4 5). It was used both in France and in Russia as a bursting charge in mines, -bombs and shells. A slightly less sensitive and less powerful mixture was Russkaya Srnes (Russian Mixture) (Ref 4), called Russkii Splav (Russian... 

RDX and HMX mixtures, wetted with not less than 15 per cent water by mass or RDX and HMX mixtures, desensitized with not less than 10 per cent phlegmatizer by mass 0391... 

The inclusion of wax-type phlegmatizing substances in the mixture facilitates the pressing of the explosive as it decreases the friction between the crystals. Thus a mixture with a higher density can be obtained by applying a lower pressure. 

The phlegmatization of PETN with nitronaphthalene recommended by T. Urbanski [6] is based on the same principle of the partial dissolution of PETN. A mixture of PETN plus 20% nitronaphthalene has approximately the same sensitiveness to impact as tetryl, and with 40% nitronaphthalene the same sensitiveness to impact as picric add. 

Phlegmatizing compounds in chlorate, and perchlorate explosive mixtures play a special role since they are essential as a combustible constituent. They are discussed in more detail on pp. 274-280. 

T. Urbanski, Influence of Non-Explosive liquids on the Detonation Rate of Solid Explosives , ArchProcesouSpalania 3 (2), 117—32 (1972) CA 78, 99944 (1973) [The author discusses the effect on the deton rate of adding w to PETN, RDX, p-Nitrotoluene or TNT in concns of from 5 to 40%. He reports that at low w concns the deton rate is minimized. As the w content increases the deton rate curve passes thru a maximum to reach a second minimum at the higher ( V 40%) level of w concn. The author concludes that the increase in deton rate can be attributed to three factors, the existence of a covolume, a phlegmatizing factor, and the result of mixing of two components, at least one of which is expl] 9) T.V. Ferris, Expansion of Methanol-Air Mixtures at Above Atmospheric Conditions , LossPrevn 8,15—19 (1974) CA 82, 45989 (1975) [Upper flammability limits were detd for various mixts of methanol with air, or a 30/70 02—N2 mixt with and without w. A rise of 12 vol % in the flammability limit above the nominal value of 36 vol % methanol in w-free air mixts is reported in the presence of liq w]... 

Many chlorate mixtures, particularly those which contain sulfur, sulfides, and picric acid, are extremely sensitive to blows and to friction. In the Street explosives, later called Cheddites because they were manufactured at Chedde in France, the chlorate is phlegmatized by means of castor oil, a substance which appears to have remarkable powers in this respect. The French Commission des Substances Explosives in 1897 commenced its first investigation of these explosives by a study of those which are listed below, and concluded 35 that their sensitivity to shock is... 

Mixtures of aromatic nitro compounds with chlorate are dangerously sensitive unless they are phlegmatized with castor oil or a similar material, but there are other substances, such as... 

Phlegmatized and pressed Cyclonite is used as a highly brisant material for the manufacture of -> Booster and -> Hollow Charges. Non-phlegmatized Cyclonite in combination with TNT is also used as a pourable mixture for hollow charges and brisant explosive charges (-> Compositions fi) mixtures of Cyclonite with aluminum powder are used as torpedo charges (Hexotonal, Torpex, Trialen). Cyclonite may also be used as an additive in the manufacture of smokeless powders. 

These are pourable mixtures of TNT RDC and aluminum (-< Torpex) containing phlegmatizing additives. 

Mixture of RDX, aluminum powder and added wax as phlegmatizer. It is used, press-molded, as a filling of anti-aircraft gunshells. Owing to the aluminum component, both an incendiary and explosive effect are obtained. 

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