Polymer oxidation and secondary cage combination of peroxyl radicals

• DOI: 10.1002/macp.1980.021810906
• Publication Date: 2003-04-15T23:35:40Z
• Authors: A. Garton; D. J. Carlsson; D. M. Wiles
• Keywords: 01 natural sciences; 0104 chemical sciences

AbstractThe photo‐oxidation of solid polymers at ambient temperatures is shown to be greatly affected by the low mobility of radicals in the solid state. When a radical pair, produced by photo‐initiation, escapes the initial polymer cage, the probability of its recombination remains high even after several propagation steps. This phenomenon, known as secondary cage recombination, has a pronounced effect on the kinetics of oxidation and on the mechanism of photostabilisation by radical scavengers. The occurrence of secondary cage recombination is demonstrated for polypropylene photo‐oxidation and a kinetic analysis is developed to predict the consequences of this effect.