PHOTO-OXIDATION AND THERMOOXIDATION OF POLYOCTENAMER - PHOTOSTABILITYOF HYDROPEROXIDES

The photo-oxidation of polyoctenamer (Vestenamer(R)) has been investig ated with the aim of systematic comparison with the photo-oxidation of polybutadiene (BR) which has been extensively studied. The major phot oproducts resulting from oxidation have been identified and quantified using well-known derivatization reactions, specific chemical analysis and physical treatments. From the author's results, photochemical evo lution of Vestenamer(R) is quite similar to that of BR, exhibiting two steps. In contrast to BR, ketone yield in oxidized polyoctenamer is v ery significant as the first stage (photo-oxidation) proceeds. In the second phase (photolytic process), photo-oxidation products undergo ph otolysis implying saturation reactions, and saturated acids appear to be the final photoproducts which accumulate in the polymer. The main d ifference beetween these two elastomeric materials is the unusually hi gh hydroperoxide content, with a maximum, observed in photo-oxidation of polyoctenamer. (C) 1997 Elsevier Science Limited.