Lead styphnate explosive power

Primary explosives differ from secondary explosives in that they undergo a rapid transition from burning to detonation and have the ability to transmit the detonation to less sensitive (but more powerful) secondary explosives. Primary explosives have high degrees of sensitivity to initiation through shock, friction, electric spark, or high temperature, and explode whether confined or unconfined. Some widely used primary explosives include lead azide, silver azide, tetrazene, lead styphnate, mercury fulminate, and diazodinitrophenol. Nuclear weapon applications normally limit the use of primary explosives to lead azide and lead styphnate. 

Primary explosives are sensitive to modest stimuli such as heat, spark, or friction application of the correct stimulus will lead to a detonation. The primary explosives used in detonators are typically extremely sensitive but not particularly powerful common examples are mercury fulminate, lead azide, and lead styphnate. In principle, the heavy metals present in most primary explosives should be a good cue for detection however, there are primary explosives that do not contain such elements. 

Aluminium detonators with lead azide and other explosives were used in the mining industry for some time, e.g. a No. 8 detonator, contained 1 g of tetryl and 0.3 g of a mixture of lead azide and lead styphnate. These were more powerful than those with a fulminate-tetryl charge, but the use of detonators with aluminium sheathing was soon forbidden in coal-mines due to the danger created by the burning of the aluminium. 

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. 

Typical primary explosives are lead azide and lead styphnate (see Fig. 1.17). The latter one is less powerful than LA but easier to initiate. Tetrazene (Fig. 2.2) is often added to the latter in order to enhance the response (sensitizer). (N.B. mercury fulminate used to be used as a sensitizer). Tetrazene is an effective primer which decomposes without leaving any residue behind. It has been introduced as an additive to erosion-free primers based on lead trinitroresorcinate. Unfortunately, tetrazene is hydrolytically not entirely stable and in long term studies decomposes at temperatures above 90 °C. Diazodinitrophenol (Fig. 2.2) is also a primary explosive and is primarily used in the USA. However, the compound quickly darkens in sun-... 

CDNTA form a white to bluish white powder, crystals, or granules. The crystals are sensitive to shock, friction, and percussion. CDNTA is a powerful primary explosive that demonstrates outstanding potential as a future replacement for mercury fulminate, lead styphnate, lead azide, and diazodinitrophenol for use in blasting caps and detonators. It should not be stored dry, and should be desensitized with dextrose, sulfur, starch, wood pulp, dextrin, or gum Arabic after preparation... 

Normal 2,4-LDNR is a less powerful explosive with even lower initiation efficiency than lead styphnate. According to Payne, 0.4 g is not sufficient for initiation of tetryl [8, 14]. 2,4-LDNR is less sensitive to impact and friction than lead styphnate. Sensitivity and brisance of practically useful lead salts of polynitroresorcines generally decrease both with increasing amotmt of lead and decreasing amount of nitrogen (Table 5.1) [8]. The main reason for the practical application of normal... 

Diazodinitrophenol -Abbreviated as DDNR it is less sensitive to impact but more powerful than mercury fulminate and lead azide. It is used with other materials to form priming mixtures, particularly where a high sensitivity to flame or heat is desired. DDNP is used as an initiating explosive to substitute for lead styphnate in non-toxic primers. 

Anon, Atlas/Aerospace No 8, 1969, Atlas Chemical Ind, Valley Forge, Pa 19481 reviewed by G. Cohn, Edit in Expls Pyrots 3(3), 1970 under the title Explosives for Actuators [LMNR (Lead Mononitroresorcinate), KDNBF (Potassium Dinitrobenzofuroxane) and BaSt (Barium Styphnate) are the three common materials used as either ignition drops or base charges in actuators, motors, switches, and matches. LMNR, a stable, low-cost compd, is always used with 5 to 40% KCIO3. KDNBF, a higher cost material, is 5 to 10 times more powerful than LMNR. 

---