The phosphorescence spectrum and photodegradation of polystyrene films

Low-temperature polarized phosphorescence spectroscopy of polystyrene polymerized under different conditions is used to detect emission from phenyl alkyl ketone endgroups in addition to triplet excimer emission from phenyl groups. The carbonyl group concentration can only be lowered by vigorous chemical reduction; and from the phosphorescence excitation spectrum, these carbonyl groups are considered responsible for the initiation of polystyrene photodegradation by solar radiation.