Ignition temperature tetryl

Hale [22] reports that the ignition temperature of ethylenedinitramine is 180°C, i.e. similar to that of nitroglycerine. On heating at 120°C its stability is of the order of that of tetryl. 

According to Domanski and Mieszkis [73] the rate of detonation, at a density of loading of 0.93 in a paper tube 10 mm dia., is 5200 m/sec (under the same conditions the rate of detonation of penthrite was approximately 6000 m/sec). Cook [58] found the rate of detonation to be 5530 m/sec at a density of loading of 1.0. The substance is similar to tetryl in sensitiveness to impact. Its chemical stability is slightly less than that of tetryl. Its ignition temperature ranges from 165 to 170°C. 

Ditetryl is more sensitive to impact than tetryl (it is exploded by a 2 kg weight falling 21-26 cm as compared with 49-51 cm for tetryl). Its ignition temperature is 214°C (that of tetryl is 196°C). It is much less stable than tetryl decomposition occurred on heating at 95°C for 4 days (tetryl withstands 185 days heating [66]). 

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. 

The substance (I) is a moderately powerful explosive it gives an expansion of 250 cm3 in the lead block. It is less sensitive to impact than trinitrotoluene. Its ignition temperature (195-200°C) is about the same as that of tetryl. It forms inflammable salts. The lead, thallous and potassium salts bum violently with a sharp report. 

According to Glowiak s researches this substance has the following pro perties Its ignition temperature with an induction period of 1 sec is 124°C. To initiate 0.5 g of tetryl, compressed under a pressure of 500 kg/cm2, the minimum charge of the phenyl diazotate of nitroform, loosely poured or compressed under a pressure of 100 kg/cm2, is 0.3 g. When compressed at higher pressure (300 kg/cm2) the charge must be increased to 0.5 g. 

In the United States a mixture of 60% cyclonite and 40% TNT was used under the name of Cyclitol as a filling for aerial bombs. The density of the cast explosive was 1.65-1.70, its rate of detonation 7800 m/sec, and in the ballistic pendulum it gave a value of 130 (100 for TNT). In the United States this mixture is considered to be only a little more sensitive to impact than TNT with a stability similar to that of cyclonite. This does not agree with T. Urbanski s [5] investigations according to which the sensitiveness to impact of such a mixture, in a powdered form, and its ignition temperature (225°C) approximate to the corresponding values for tetryl. 

Impact sensitivity Ignition temperature (°C) Initiating efficiency (g) Tetryl TNT ... 

Lead picrate is considered highly sensitive to mechanical impact and thermal stimuli [6]. The anhydride is more sensitive to mechanical stimuli than the hydrates. Impact sensitivity of anhydride is significantly higher than the sensitivity of mercury fulminate (4 cm/0.5 kg vs. 24 cm for MF) [7,8]. Handling of lead picrate anhydride represents the same level of risk as handling of lead styphnate. The ignition temperature is 281 °C (explosion takes place instantaneously or within 1 s) [7]. The formation of lead picrate by reaction of tetryl (which decomposes to picric acid) with lead azide is reported as a possible reason for the higher sensitivity of this mixture compared to pure LA [6]. 

Table 8.6 Impact sensitivity, ignition temperature and initiating efficiency against tetryl for certain tetrazole salts...

Impact sensitivity Initiating efficiency (against tetryl) Ignition temperature ... 

Properties Yellow powder. Sp. gr. 2.05. M. P. about 120°. Ignites at about 250°. B. P. 444.6°. Ignites readily and therefore facilitates ignition of black powder and other ignitible mixtures. Sulfur decreases the temperature of detonation of TNB, TNT, and picric acid to a lesser degree sulfur lowers the temperature of detonation of Tetryl and Pentrite. Sulfur raises the temperature of detonation of Hexogen and increases the sensitivity of Tetryl to shock (maximum at 10 per cent sulfur). ... 

TETRYL or 2,4,6-TETRYL (479-45-8) A powerful oxidizer and heat-, friction-, and shock-sensitive high explosive. Explodes in elevated temperatures above about 482°F/250°C. The reaction may take about 0.1 second, but this material can explode after a delayed period in lower temperatures (16.6 minutes at 320°F/I60°C). Ignition or explosion on contact with reducing agents, combustible materials, fuels, hydrocarbons, hydrazine, powdered metals, organic substances, trinitrogen difluoride. 

Basic lead azide—3Pb(N3)2-2PbO— is much less sensitive to mechanical stimuli than LA but it keeps relatively acceptable explosive properties. It explodes violently when heated, with an explosion temperature of 350 °C at heating rate 5 °C min Basic lead azide is not attacked by moisture like LA at 30 °C and 90 % humidity during 3 months. Ignition efficiency is 0.07 g for tetryl, and bulk... 

When a 0.5 gram sample of tetryl is heated at a rate of 20°C per minute, ignition occurs between 190°C and 194°C. If the temperature of a sample is held at 180°C ignition occurs in 40 seconds. The minimum primary charges necessary for reliable detonation of tetryl with mercury fulminate is 0.20 to 0.29 grams and with lead azide is 0.025 to 0.10 grams. Tetryl containing 60 percent water cannot be detonated by a commercial detonator. Shock sensitivity as measured by the gap tests are summarized in table 8-30. 

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