THE PHOTOOXIDATION OF POLYMERS - 3 - THE MAIN REACTION OF CHAIN PROPAGATION IN POLYSTYRENE PHOTOOXIDATION

The photochain dissociation of peroxide macroradicals followed by effe ctive absorption of oxygen and liberation of volatile products of dest ruction (H2O and CO2) in the quantities comparable with the quantity o f the absorbed O-2 is shown to be the main reaction of the chain propa gation in photo-oxidation of polystyrene. (The reaction chain length i s 10(2)-10(3) links.) The photochain reaction mechanism is confirmed b y the special experiments with the participation of light at the stage of chain propagation when the photo-oxidation of polystyrene having t he peroxide macroradicals was carried out under the action of longwave light with lambda greater than or equal to 440 nm, that was inactive to the starting polymer. (C) 1998 Elsevier Science Ltd. All rights res erved.