Other styphnates

Tompkins and Young [50] examined the thermal decomposition of barium styphnate and found it to be similar to that of lead styphnate hydrate (Fig. 54). 

The point of inflexion of the decomposition curve occurs after 50% of the substance has decomposed. The energy of decomposition is 36.5 kcal/mole. 

According to T. Urbanski and Kruszynska [41] thallium styphnate has similar properties to those of lead styphnate. The former, however, is much more sensitive to impact than the latter. Their sensitiveness to temperature is similar contact with a metal surface heated to 351°C causes explosion after 1 sec. The activation -energy of thermal decomposition is nearly 80 kcal/mole. 

This substance is prepared by the action of a hot solution of lead nitrate on a solution of sodium dinitroresorcinate. The lead salt is precipitated as the solution cools. Lead dinitroresorcinate ignites from a direct flame readily and burns with great velocity. Its initiating action is weaker than that of lead styphnate and it is less sensitive to impact and friction than styphnate. It has therefore recently found application as a component of cap compositions. It is valuable because it is safer to handle than styphnate. The preparation of dinitroresorcinol is discussed in Vol. I, p. 536. 

---

He describes a process for fine milling which results in uniform particle size distribution in the 5-micron range. Milled Basic LSt resembles other styphnates in color texture, It should be stored with a water-alcohol soln or isopropyl ale for i -lb portions. To prevent improper use, all styphnates, in or out of storage, should be properly identified (Ref 16)... 

Benzene must be employed as the solvent for anthracene styphnate since most other solvents lead to dissociation. 

Hydrocarbon B.P. M.P. 20- 4 20 Picrate Aroyl- benzolc Acid Compound with 1 3 5-Trlnltro-benzene Styphnate Other Derivatives... 

Woodring, USP 2206652 (1940) CA 34,7610 (1940) [Primer compn contg Pb, Na or Cd salts of trinitrophloroglucinol with Pb Styphnate and other ingredients] 10) R- Schmitt, SS 38, 149 (1943) [Quant estimation of trinitrophloro-glucinol by pptn with phenyl ad ridine soln]... 

Three beakers containing lead styphnate were being heated in a laboratory oven to dry the explosive salt. When one of the beakers was moved, all 3 detonated. Other heavy metal salts of polynitrophenols are dangerously explosive when dry [1], The desensitising effect of presence of water upon the friction sensitivity of this priming explosive was studied. There is no effect up to 2% content and little at 5%. Even... 

On the other hand, humidification can prevent buildup of dangerous electrostatic charges. This is especially important in the handling of such primary explosives as Pb Azide or Styphnate. General references on humidity control humidification are Refs 2, 4, 5 6... 

Normal lead styphnate (LS) [Structure (2.10)] was first reported by Von Herze in 1914, although its basic salt, that is, basic LS was prepared by Griess [7] way back in 1874, by the reaction of acidified magnesium styphnate with lead nitrate/acetate in hot aqueous solution. It is precipitated as mono hydrate and consists of reddish-brown rhombic crystals. It is filtered off, washed with water, sieved through a stainless steel sieve and dried. Like other initiatory explosives, it is kept in wet conditions until used. 

Fig. 49. Diagram of the design and operation of a reactor for the manufacture of lead azide and other primary explosives (tetrazene, lead styphnate and lead picrate).

A method of preparation of the neutral salt (I) has been given by Herz [45]. He claims that the anhydrous salt crystallizes from an aqueous solution. In the light of other authors works (e.g. Zingaro), it is doubtful whether in such conditions, an anhydrous salt can really be formed. The dehydration of neutral lead styphnate (I) was investigated by Zingaro who found that complete dehydration may be effected by heating the substance at 115°C for 16 hr. At higher temperatures (135-145°C) dehydration takes place more quickly (Fig. 53). Stettbacher [46] reported that in a moist atmosphere anhydrous lead styphnate absorbs water to reform... 

From the magnesium styphnate solution so prepared, 86.4 1. of liquid was decanted, leaving the lower layer in which the sediment was collected. This solution was heated to 60°C, while stirring, and 22.71. of 34% solution of lead nitrate, s.g. 1.274 (31°Be) was then poured into it during a period of 20-30 min, while stirring continued and the temperature was maintained at 60°C. When the solutions were mixed, the contents of the reactor were cooled as quickly as possible to 25°C when this temperature has been reached the stirrer was stopped and the precipitated sediment of lead styphnate was allowed to settle. The liquid from above the sediment Was then decanted, and the latter was first washed out of the reactor by a stream of water, and transferred onto a cloth filter, where it was washed again as is the custom with other primary explosives. From the above mentioned amounts of raw material about 8 kg of lead azide was obtained. 

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. 

One lead- in was in contact with the primer plug, the other with the igniter retainer. The bridge and the fiber assembly were encased with a small quantity of LSt(Lead Styphnate) colored green with NC lacquer and around this was placed loose BkPdr chge... 

Primary explosives have a high degree of sensitivity to initiation through shock, friction, electric spark or high temperatures and explode whether they are confined or unconfined. Typical primary explosives which are widely used are lead azide, lead styphnate (trinitroresorci-nate), lead mononitroresorcinate (LMNR), potassium dinitrobenzo-furozan (KDNBF) and barium styphnate. Other primary explosive materials which are not frequently used today are mercury azide and mercury fulminate. 

Many other ignition compns have been patented such as bis-triethyl lead styphnate, triethyl lead -basic lead styphnate, triethyl lead azide, mono -triethyl lead azo-aminotetrazole, bis-triethyl lead azoaminotetrazole, triethyl lead azidodithio-carbonate, diethyl lead diazide bis-basic diethyl lead styphnate, etc. The ignition compns mentioned above have an "overall lag of less than 0.0009 secs when fired at 12 amps, but in some cases this lag is even smaller, viz, 0.0002, 0.0003, 0.0004, 0.0005 or 0.0006secs... 

A good description of tests for Lead Azide (LA), Mercuric FuIminate(MF), Diazodinitro-phenol(DADNPh)j Lead Styphnate(LSt) St Tetracene are given in Ref 22a, pp 267-69. The same tests are described in Ref 27,pp 1345-47 These tests are not repeated here but will be given, together with other tests under individual compds... 

The disruption and fragmentation of the reactor core as a result of the excursion hurled all the capsules from both locations at least 500 feet away. The Pb styphnate sample which had been mounted on the pressure vessel showed evidenoe of a high-order detonation, which was assumed to be the result of the high rate of energy input from the KIWI—TNT test. This assumption was based upon several premises. Primarily, the possibility of the material detonating as a result of impact rather than by radiation did not seem reasonable, since the other sample... 

See under Lead Styphnate, Basic and Lead Styphnate, Normal in Vol 5, D1277-L to D1278-R and D1278-L to D1288-L. Other lead salts of trinitroresorcinol are listed as such on D1288-L of Vol 5... 

Pb Azide is used alone or in mixts with other expls such as Pb Styphnate (see Stifmto de plomo) in primers and detonators... 

K. Bahadur, Study of Some Double Salts of Lead Useful as Initiating Explosives by Thermogravimetry and Thermometric Titrations , Symp-ChemProblConnectedStabExpls[Proc], 3rd 1973 (Pub 1974), J. Hansson, Ed, CA 83, 30455 (1975) [The author reports that Lead-5,5 -Diazoaminotetrazolate Styphnate was found to be superior as an initiator expl to other double complexes with azotetrazolic acid or 5-nitra-minotetrazolic acid investigated, and it is recommended as an ideal replacement for Fb Azide... 

Aroyl- benzoic acid °C Compound with 2,4,7-trinitro-9-fluorenone Compound with 1,3,5-trinitro-benzene Styphnate Other derivatives °c... 

Other substitutes for lead styphnate included lead salts of many organic compounds, none of which gained widespread acceptance. 

---