Lead styphnate density

Lead styphnate is a poor initiating explosive which when dry is very sensitive to friction and impact, to electrostatic discharge, and to flame. Its main use is as an additive to lead azide to improve flame sensitiveness (see p. 101). When pressed to a density of 2-6 g ml-1 it has a velocity of detonation of4900 m s l. 

Lead styphnate (neutral salt I) is practically insoluble in water (0.04 g in 100 ml of water, at 15°C) and in the majority of organic solvents. It is very stable at room and elevated temperatures (e.g. 75°C) and is not hygroscopic. In a moist atmosphere, at room temperature, it absorbs only 0.05% of water. Its specific gravity is 3.1, its apparent density, 1.0-1.6. 

Resorcinol nitrates readily to the trinitro compound, yellow prisms from water or alcohol, m.p. 175.5°. Styphnic acid is more expensive and less powerful than picric acid. Liouville67 found that styphnic acid exploded in a manometric bomb, at a density of loading of 0.2, gave a pressure of 2260 kilos per sq. cm., whereas picric acid under the same conditions gave a pressure of 2350 kilos per sq. cm. It did not agglomerate to satisfactory pellets under a pressure of 3600 kilos per sq. cm. It is a fairly strong dibasic acid, and its salts are notably more violent explosives than the picrates. Lead styphnate has been used to facilitate the ignition of lead azide in detonators. 

Primary explosives include mercury fulminate [Hg(ONC)2, melting point 160°C with explosion, density 4.2], lead azide [Pb(N3)2, density 4.0], basic lead styphnate (lead trinitroresorcinate), diazodinitrophenol, and tetrazine (a complex conjugated nitrogen compound, melting point 140 to 160°C with explosion). Most priming compositions consist of mixtures of primary explosives, fuels, and oxidants. 

The effect of density on the dielectric strength of dextrinated lead azide, normal lead styphnate, and silver azide was also investigated (Figure 16). The dielectric strengths of dextrinated lead azide and normal lead styphnate increased with density. The breakdown level of silver azide was relahvely unaf-... 

However, when lead azide, lead styphnate, mercury fulminate, RDX, TNT, and PETN were subjected to bombardment with a negative pion beam, no explosions or decompositions were observed for any of the explosives. The analysis had predicted initiation only for RDX. Also it had indicated that nuclear fission events would produce higher energy densities and greater temperature increases than were actually observed. 

Only limited data were obtained for lead styphnate and LMNR. One initiation was achieved in lead styphnate. Assuming a sound speed of 2.5 km/sec and a density of 2.75 g/ml, the stress transmitted to the lead styphnate that produced initiation was estimated at 4.3 kbar, while the highest stress that did not produce initiation was 3.1 kbar. The pulse duration was of the order of 0.4 psec. With LMNR and the same pulse, no initiations were achieved, the highest stress transmitted to the LMNR being in the order of 8 kbar. 

Normal lead styphnate forms a monohydrate with crystal density from 3.06 to... 

An alternative preparation method involves the ammonia salt of 2,4,6-trinitroresorcine [24, 64, 66]. The formation of the desired form and crystal shape depends on reaction conditions. The addition of 2-mononitroresorcinol in an amount between 0.1 and 5 % is sometimes employed in the preparation of the red form to improve its bulk density and flowability [24, 64]. The presence of foreign substances in the starting 2,4,6-trinitroresorcine (added in the suUbnation operation in the preparation of styphnic acid) has also a significant influence on the shape of basic LS crystals [70]. Various procedures are patented for preparation of red [24, 64,65, 71] and yeUow [39, 64—67] basic lead styphnate. Just like LS, the basic LS can also be prepared as a jelly (see lead styphnate). 

Leopold, H.S. Effect of loading density on the hot wire initiation of normal lead styphnate and barium styphnate. Report NOLTR-70-96, AD716024, U.S. Naval Ordnance Laboratory, White Oak, Silver Spring (1970)... 

Nickel hydrazine nitrate is not easily detonated by flame or heat in charges of a few grams even when mixed with lead styphnate, picrate, or RDX. These mixtures were loaded in a blasting cap and initiated but the best that has been observed was a deflagration [6, 16]. Other results have been obtained by Talawar et al. [18]. They made a research of the applicability of NHN in detonators. NHN is ignitable by the flame of a match, a safety fuse, or a hot wire. Whether it develops detonation strongly depends on its confinement and its density. 

LS is often used in bridge-wire compositions where it is in direct contact with wire heated by an electric current. An interesting study of the effect of loading density on the hot wire initiation of lead and barium styphnates was carried out by Naval Ordnance Laboratory [42]. It was found that the energy required for the initiation remained constant and the time to ignition decreased as the loading density increased. 

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