Photochain destruction of excited peroxide polystyrene macroradicals

Photo-oxidation of the polystyrene (PS) includes two mechanisms—a hydroperoxide one and a photochain one (caused by the photosensitivity of peroxide macroradicals). A hypothetical scheme of the photochain dissociation of excited peroxide radicals has been proposed. The latter are destroyed during photo-oxidation of polystyrene to H2O and CO2. More then 90% of the oxygen absorbed is consumed according to the photochain mechanism.