Tetryl thermal decomposition

Cook (Ref 1), in describing thermal decomposition of some HE s conducted in the quartz spring apparatus (described in Ref 1, p 175 and shown there in Figs 8.1a 8.1b), stated that PETN, RDX, Tetryl and to a small extent TNT decomposed autocatalyti-cally. EDNA followed the first-order decomposition law only until about 5% of the explosive had decomposed and then the reaction stabilized. The term autostabilization was applied here on the supposition that one of the condensed decomposition products of EDNA which accumulated in the explosive apparently tended to stabilize the bulk of expl and thus slow down the decomposition. After about 10% of the expl had decompd, however, the "autocatalysis developed. 

According to Farmer [32] the activation energy of the thermal decomposition of tetryl =60.0 keal and log 5=27.5. Hinshelwood [38] reports similar values. A. J. B. Robertson [41] found, however, that at higher temperatures (211-260°Q =38.0 kcal and log 5=15.4. According to Szyc-Lewanska [42] at still higher temperatures (260-300°C) the activation energy is even lower, viz. E= approximately 20.0 kcal (based on the data given above [40]). 

Mass spectra of the important explosives RDX, HMX, TNT, TNB and Tetryl were first briefly reported by Meyer (Ref 34) and later investigated in greater detail with high resolution and labeling techniques by Bulusu et al (Ref 45). Mass spectrometric studies of the photodecomposition of labeled dimethyl-nitramine (Ref 56) and the thermal decomposition of HMX and RDX (Refs 27 31) illustrate the application of these techniques to studies of reaction mechanism and bond dissociation processes. Nitroguanidines have only recently been investigated by Beynon (Ref 35)... 

Thermal Decomposition. Betw 80 140° a reversible deamination occurs with the loss of 4 moles of ammonia, and betw 240 280° an irreversible exothermic reaction occurs resulting finally in an expln at ca 280°. A residue of Ni oxide contg some chloride is left (Ref 17) Hydrazine Complex. A complex with the empirical compn Ni(C104)2-Ni(0H)C104.5N2H4.-H2 0 has been reported to be a pale blue solid (Ref 5) with the following expl props Effectiveness as a Detonator. Wts of the subs which will initiate the following expls are Tetryl O.lOg, TNT 0.15g, TNAns 0.45g (Ref 7) Explosion Temperature. 175° (Ref 6)... 

The stirrers were made of stainless steel, since kinetic studies - showed that stainless steel does not affect the rate of thermal decomposition of the substances investigated. In order to choose the method of stirring, the viscosity and its temperature dependence were determined in an Ostwald viscometer for DINA (dinitroxydiethylnitramine) and for tetryl. The viscosity of DINA at the temperatures of the experiment is similar to that of water at room temperature. Therefore water was used as a model of DINA in the preliminary estimation of the efficiency of the stirring. A propeller stirrer was used for stirring DINA. In order to avoid the distortion of the surface of the stirred substance the axle of the stirrer was placed... 

ITC heating of Iclryl increases the rate of burning of the substance. Tlus was already shown by Andreev (V ol. Ill, Fig. 6), by his later work [94J and substantiated by M. M. Jones and Jackson [87] and Japanese authors [86). Tire latter authors found for example that preheating the sample to 180 C lowers its ni.p. by 20 C and the decomposition temperature by 12 C. They also examined the samples of tetryl heated at 165°C for 3 hours by liquid chromatography, by TLC, NMR and mass specirography. They found that 2,4.6-trinitroanisol and picric acid are fonned on the thermal decomposition of tetryl at I60--200 C. 

Burning of tetryl is discussed in the monograph by Glazkova [92] and reference is given to the early work of Hinshelwood [93] who pointed out that thermal decomposition of tetryl produces picric acid which plays the part of a catalyst of the decomposition. The rate of burning of tetryl under pressure increases by addition of potassium bichromate, according to Glazkova [92]. 

Thermal decomposition of tetryl was reviewed by Dubovitskii and Korsun-skii [4). 

Recently Kishorc and laye 1116] examined thermal decomposition of cyclonite by differential scanning calorimetry. The curves of the decomposition arc of an S shape (similar to those of tetryl — Rg. 53). Isothermal curves are similar to Figs 55 and 56. Tlie author calculated the value of decomposition of cyclonite in an open vessel as being 41 2 kcal/mol. They also reported the values of obtained by other authors. In addition to those given in Vol. HI, p. 83 (by Robertson), they are those of ... 

Hara, Kamei and Osada 86] obtained similar results.. Among the gases from the decomposition of tetryl they also found methane. They carried out the experiments at temperatures from 150 to 175 0. By differential thermal analysis they found the endothermic (negative) peak at I31 C due to the melting of the substance and exothermic decomposition occurred at 160 C. They calculated the activation energy as being 35 kcal/mol. This is in agreement with formerly obtained results (Vol. HI, p. 53). 

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