Picric acid explosive power

It is prepared by the direct nitration of toluene with a mixture of nitric and sulphuric acids. TNT is a very stable, violent and powerful high explosive, but less sensitive to shock and friction than picric acid. It is widely used as a filling for shells, bombs, etc. often mixed with ammonium nitrate and other high explosives. The lower grades of TNT may contain isomers which under hot storage conditions may give rise to exudation. 

VIII. Explosive Characteristics. Picric Acid is generally considered to be a relatively insensi tive but brisant expl. On a qualitative sensitivity scale of comparing common expls, PA would be judged to be more sensitive than TNT but appreciably less sensitive than Tetryl. Its power and brisance are also similar to those of TNT (112% TNT in the Ballistic Mortar 101% of TNT in the Trauzl Block and 107% in the plate dent test (Ref 48). In this section we will consider the steady detonation parameters. initiation characteristics and potential hazards of PA... 

Liquid mixtures with detonable materials (picric acid, nitromethane) were extremely powerful explosives, and those with nitrobenzene or dimethylformamide less so. 

Norris, W. P. et al., Aust. J. Chem., 1983, 36, 306 A powerful high explosive, of comparable sensitivity to dry picric acid. 

It is an explosive of lower power, but of greater impact- or friction-sensitivity than picric acid, so should not be stored in bottles with ground-in stoppers. 

Secondary explosives (also known as high explosives) are different from primary explosives in that they cannot be detonated readily by heat or shock and are generally more powerful. Secondary explosives can be initiated to detonation only by a shock produced by the explosion of a primary explosive. Widely used secondary explosives include trinitrotoluene (TNT), tetryl, picric acid, nitrocellulose, nitroglycerine, nitroguanidine, cyclotrimethylenetrinitramine (RDX), cyclotetramethylenetetranit-... 

Trinitroanilina o Picramide (TNA) is an explosive equal in power to PA (Picric Acid). Its props are described in Belgrano (Ref 31, pp 270—71) but uses are not indicated... 

Explosifs 6 I aluminium. Fr for Aluminized Explosives. Several Fr formulations are listed in Vol I of Encycl under ALUMINUM CONTAINING EXPLOSIVES, on p A146-L. Examination in 1902 by CSE (Commission des Substances Explosives) showed that some of these exp Is, as, for example, Formula. 226 (p A146 L)> were more powerful than PA (Picric Acid). More recently (1948 1950), Medard (p A148-L) determined the properties of die following Fr aluminized explosives ... 

In order to calculate the power index of an explosive, its explosive power (as calculated above), is compared with the explosive power of a standard explosive (usually picric acid) that is, (Equation 1.16) ... 

Tablel.7 Power index values of some primary and secondary explosives (standard-picric acid).

Cyclonite is a very important explosive. The outstanding properties of RDX as an explosive are high chemical stability, not much lower than aromatic nitro compounds and high explosive power which considerably surpasses that of aromatic nitro compounds such as TNT and picric acid. RDX has a detonation velocity of8600 ms"1 and a detonation pressure of 33.8 GPa at a density of 1.77 gem"3. RDX is used in mixtures with TNT (Hexotols, Cyclotols, Compn. B) wax (Composition A) aluminum (Hexals) aluminum and TNT (HBX, Hexotonal, Torpex) etc. 

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. 

The substance possesses quite uncommon and valuable explosive properties. It is more powerful than tetryl, and considerably less sensitive to impact (as sensitive as picric acid). However, its acidic properties limit its use to a great extent. In this respect it resembles picric acid. Even so ethylenedinitramine, under the name of Haleite, has been accepted in the United States as a military explosive. During World War II, production in that country was carried out by the method outlined above according to eqn. (17)... 

According to a number of authors, the explosive power of tetryl, determined in the lead block, varies between 340 and 390 cm3, i.e. between 114 and 120% of the value for picric acid. 

It is an explosive of approximately the same power as picric acid. 

Romburgh [3] was the first to prepare this substance both by nitrating ethyl-aniline and by nitrating diethylaniline. It is comparable to tetryl in its physical and chemical properties. As an explosive it is weaker than tetryl. Its sensitiveness to impact and its explosive power, measured in the lead block, are somewhat greater than those of picric acid. 

The explosive properties of hexanitrodiphenyl-/ -hydroxynitraminoethyl nitrate are similar to those of pentryl. It is slightly more stable on heating its ignition temperature lies between 390 and 400°C. It is somewhat less sensitive to impact than pentryl and rather more powerful (by 3%) in the lead block test. It requires a stronger initiator than pentryl, tetryl or picric acid, but a weaker one than trinitrotoluene. 

Investigations carried out at that time revealed the outstanding value of cyclonite as an explosive its high chemical stability, which is not much lower than that of aromatic nitro compounds, and its great explosive power, which considerably surpasses that of aromatic nitro compounds, such as trinitrotoluene and picric acid. 

Data from the Griesheim factory [1] show that this may be avoided by adding other aromatic nitro compounds, e.g. TNT, to the picric acid. The addition of even a small amount (5-10%) of such a substance facilitates melting without seriously decreasing the explosive power of the picric acid. 

In addition to aluminium, calcium silicide or ferro-silicon, the use of silicon was also recommended. The comparative figures illustrating the effect of the addition of these compounds on the strength of the explosive have been given by Sar-torius [70] (Table 59). The power is expressed in terms of expansion in the lead block (taking picric acid as 100). 

Picric acid is a strong acid, very toxic, soluble in hot water, alcohol, ether, benzene and acetone, and is a fast yellow dye for silk and wool. It attacks common metals, except for aluminium and tin, and produces salts which are very explosive. The explosive power of picric acid is somewhat superior to that of TNT, both with regard to the strength and... 

RDX has a high chemical stability and great explosive power compared with TNT and picric acid. It is difficult to dissolve RDX in organic liquids but it can be recrystallized from acetone. It has a high melting point which makes it difficult to use in casting. However, when it is mixed with TNT, which has a low melting temperature, a pourable mixture can be obtained. Some of the properties of RDX are presented in Table 2.15. 

The value for the explosive power is then compared with the explosive power of a standard explosive (picric acid) resulting in the power index, as shown in Equation 5.13, where data for <2(picric acid) and E(picricacid) are 3250 kJ kg 1 and 0.831 dm3 g 1, respectively. 

Table 5.14 The power index of some primary and secondary explosive substances taking picric acid as the standard...

Perchlorate Ammonium perchlorate [CAS 7790-98-9] (NH(4)CLO(4)) is a white crystalline substance. It is a powerful oxidizing material. A1J is the oxidizer used in the solidroekel boosters on the space shuttle. It is stable in pure form at ordinary temperature, but decomposes at a temperature of 150 degrees C or above. It becomes an explosive when mixed with finely divided organic materials. AP exhibits the same explosive sensitivity to shock as picric acid (Class A explosive). Sensitivity to shock and friction may be great when contaminated with small amounts of some impurities such as sulfur, powdered metals and carbonaceous materials. AP may explode when involved in fire. Periodate Ammonium penodate NH4IO4. white solid, moderately soluble. 

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. 

At ordinary temperatures tetryl appears to be perfectly stable. Current methods of purification insure the absence of occluded acid. It is more powerful and more brisant than TNT and picric acid, though distinctly more sensitive to shock, and is probably the best of all the common explosives for use in boosters and reinforced detonators. Koehler97 reports pressures in the mano-metric bomb (density of loading = 0.3) and temperatures produced by the explosions, as follows ... 

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... 

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