Benzoyl acetyl peroxide, decomposition

The various initiators are used at different temperatures depending on their rates of decomposition. Thus azobisisobutyronitrile (AIBN) is commonly used at 50-70°C, acetyl peroxide at 70-90°C, benzoyl peroxide at 80-95°C, and dicumyl or di-t-butyl peroxide at 120-140°C. The value of the decomposition rate constant kj varies in the range... 

The decomposition of the unsymmetrical peroxides (Table 82) does not present anything particularly unusual in rates. The enthalpy of activation for the decomposition of benzoyl phenylacetyl peroxide and phenylacetyl peroxide are similar. An analysis of the products from the decomposition of acetyl benzoyl peroxide in conjunction with kinetic datahaveled Walling and Cekovic to suggest an induced decomposition which is initiated by methyl radical attack on the aromatic ring, viz. 

Tetrafluorobutylsulfonylbicyclo[4.1.0]heptane-7-carbonitrile (1) was obtained by the decomposition of phenyliodonium cyano(tetrafluorobutylsulfonyl) methanide, with bis(acetyl-acetonato)copper as catalyst and traces of benzoyl peroxide, in the presence of cyclohexene. It has been proposed that the reaction proceeds by the initial formation of a cyanocarbene, which then attacks the C-C double bond of cyclohexene. ... 

The presence of free radicals in the reaction of tertiary amines and benzoyl peroxide has been observed by electron spin resonance (ESR) spectroscopy [67-69]. The reaction of amines with acyl peroxide is much more rapid than the thermal decomposition of the peroxide alone [70]. For example, benzoyl peroxide [53] with dimethylaniline at 0 C in styrene or chloroform exhibits an apparent second-order rate constant of 2,3 X 10 sec However, acetyl [41] and lauroyl peroxide [71,72] react somewhat slower. 

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