Effect of polymer structure on the formation of degradation products Photodegradation of polystyrene

Photodegradation of atactic and syndiotactic polystyrene has been investigated using
optical absorption and Fourier Trans form In frared (FTIR) spectral an alysis and
electron spin resonance (ESR) spectroscopic measurements.Photoirradiations were
carried out with radiation from a medium pressure mercury lamp (polychromatic
radiation) and monochromatic radiation using the Okazaki Large Spectrograph (OLS).
Oxygenated products formation was favored in the photodegradation of atactic
polystyrene,while conjugated doubl e bond formation in syndiotactic polystyrene is
superior to that in atactic polystyrene.Longer conjugated doubl e bonds were found in photoirradiated syndiotactic polystyrene.The difference in the products formed was discussed on the basis of the structures of both polymers.The threshold wavelength for oxygenated products formation estimated from the monochromatic radiation experiments was found to be around 300 nm for both polymers.