ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Thermal Decomposition of Benzoyl Peroxide in Solid State

M. Lazár and P. Ambrovič

Institute of Polymers, Slovak Academy of Sciences, Bratislava 9

Abstract: The course of decomposition reaction in different solid media has been investigated by differential calorimetry. The decomposition of benzojd peroxide in solid state differs from the decomposition in solution by a notable autocatalytic effect of decomposition reaction. The autocatalytic character of benzoyl peroxide decomposition remains in dilute solid media, too. But the induction times are shortened in the presence of different admixtures. The effect of temperature on the isothermal decomposition of benzoyl peroxide in solid medium shows that the presence of other molecules decreases the apparent activation energy of benzoyl peroxide decomposition both in the stage of initiation and in the stage of fast branched chain decomposition. The results obtained are discussed and interpreted from several points of view. The present knowledge supports the idea that the crystal lattice of benzoyl peroxide is responsible for the rate decrease of spontaneous decomposition in comparison with reaction rates in solutions. On the other hand, the ordered regions of benzoyl peroxide molecules enable a fast induced chain decomposition of peroxide. The admixtures accelerate the spontaneous but slow down the induced decomposition of benzoyl peroxide owing to irregularities in crystal lattice.

Full paper in Portable Document Format: 2311-12a881.pdf

Chemical Papers 23 (11-12) 881–894 (1969)