Abstract

Photoscission of GR-S in ethylbenzene solution has been shown to require the interaction of oxygen. In principle then an antioxidant which is not a photosensitizer should function as a light stabilizer. The cause of the failure of the antioxidants studied to function as light stabilizers of GR-S is shown to be related to the occurrence of a very low rate of oxidation of the GR-S despite the presence of the antioxidant. The cause of the viscosity rise in GR-S solutions on autoxidation appears to be the formation of an intermolecular peroxide bond which is subject to induced scission.