Diethyl peroxide, decomposition

This means at least 13 % chain reaction. The above estimate is supported by the results of Leggett and Thynne , who have shown that the diethyl peroxide decomposition, which should be even more susceptible to chain sensitization than diethyl peroxide ( 4 < 4), in the presence of nitric oxide has an activation energy 2 kcal.mole higher than in the uninhibited system. The additional reactions of importance are... 

The thermal decompositions described above are unimolecular reactions that should exhibit first-order kinetics. Under many conditions, peroxides decompose at rates faster than expected for unimolecular thermal decomposition and with more complicated kinetics. This behavior is known as induced decomposition and occurs when part of the peroxide decomposition is the result of bimolecular reactions with radicals present in solution, as illustrated below specifically for diethyl peroxide. 

A small contribution from the chain decomposition would be difficult to detect and would lower both the A factor and the activation energy. A similar argument applies to diethyl peroxide, and the measured (11) low A factors and activation energies are convincing evidence of the chain contribution. Leggett and Thynne (16) recently measured the A factor and activation energy for the decomposition of diethyl peroxide and found them to be normal. 

Experimental Measurements of Self-Heating in the Explosive Decomposition of Diethyl Peroxide , I2thSympCombstn, Poitiers, France, July 14-20, 1968. Abstracts of Papers, pp 100-02... 

That tills high factor is not characteristic of peroxides in general is shown by the investigation of the thermal decomposition of diethyl peroxide. Harris and Egerton os measured the kinetics of the thermal decomposition in a static system by following the... 

Nearly all peroxides decompose readily, and many of the lower members are explosive. The decomposition of diethyl peroxide has been studied under both non-explosive and explosive conditions [99—102(b)]. The reaction is first-order and the variation of rate coefficient with temperature (uncorrected for any self-heating) is represented by fe = 1.6 x 10 exp(—34,000/i T) sec". At around 200 °C the course of the slow reaction may be represented by [102(a)]... 

The most extensive study of thermal etplosion theory was carried out by Gray et al." on the decomposition of diethyl peroxide in the gas phase. The study was carried out under conditions where convective heat transfer within the reactant mass is negligible and where heat generation by the reactant and losses by conduction therefore determine the course of events. Their findings are in excellent qualitative agreement with the predictions of thermal theory and furthermore the quantitative agreement is remarkable, in view of the various assumptions of stationary-state conductive theory and the deviation in practice of the actual reaction system from these. The experimental results may be summarized as follows ... 

Tetraethylammonimn bromide was recrystallized from the saturated acetonitrile solution by addition of diethyl ether abundance. The salt purity (99.6 %) was determined by aigentmmnetric titration with potenciometric fixation of the equivalent point. Acetonitrile was purified according to [17]. Its purity was controlled by electroconductivity % value, which was within (8.5 0.2)T0 Om sm at 303K. Cumene was subjected to acid - alkali purification with subsequent desiccation under calcium chloride and distillation according to [18]. Reactions of cyclohexanone peroxides decomposition were carried out in the glass... 

The decomposition of di- e -butyl peroxide in the presence of diethyl phosphite and an aromatic substrate leads to free-radical phosphination, Eqs. (43) and (44). 

Pyrolysis of the phosphorodichloridothioate (59) at 550 °C gives mainly dibenzothiophen and a smaller amount of the cyclic phosphonochlorido-thioate (60). Thermal decomposition of di-t-butyl peroxide in triethyl phosphate gives rise to diethyl methyl phosphate in a reaction which may be interpreted as resulting from attack of methyl radical on the phosphoryl oxygen. An extension of this mechanism accounts for the formation of (61) from tri-isopropyl phosphate under the same conditions. 

Many incidents involving explosions have been attributed, not always correctly, to peroxide formation and violent decomposition. Individually indexed incidents are 2-Acetyl-3-methyl-4,5-dihydrothiophen-4-one, 2807 Aluminium dichloride hydride diethyl etherate, Dibenzyl ether, 0061 f 1,3-Butadiene, 1480 f Diallyl ether, 2431 f Diisopropyl ether, 2542... 

Thne-of-flight (TOF) mass spectrometric analysis of the pyrolysis fragments of di-t-butyl peroxide suggests t-BuCO as the primary product, followed by decomposition of this radical into CHj.253 Elsewhere, the kinetics of the pyrolysis of dimethyl, diethyl, and di-t-butyl peroxides in a modified adiabatic bomb calorimeter have been investigated.254 The lifetime of acyloxy radicals, generated by the photolysis or thermolysis of acetyl propionyl peroxide, have been studied. Chemical nuclear polarization has been used to determine the rate constant for the decarboxylation of these radical intermediates.255... 

Elements of Group III and the n-butyl analogue, have been obtained by treating the dialkoxy-chloroborane with hydrogen peroxide in diethyl ether.216 A mechanism for the thermal decomposition to boric acid and B(OR)3 is postulated in which the first stage is homolytic cleavage of the O—O bond. 

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