Study of the effect of ultraviolet radiation on the photodegradation of polystyrene films doped with Schiff bases

Abstract

The research includes doping polystyrene (PS) films by Schiff base compounds as photostabilizers and studying their efficiency in reducing photo-decomposition. The Schiff bases compounds were prepared by the condensation reaction of 2-hydroxybenzohydrazide with benzaldehyde derivatives (p-chlorobanzaldehyde, 4-(dimethylamino) benzaldehyde, 4-methoxybenzaldehyde and 2-hydroxy-4-methoxybenzaldehyde). Doped polystyrene films were synthesized by the addition of these bases at low concentration of 0.5% by weight of the polymer. The films were exposed to the u.v. light at 313nm wavelength for 300h, and the photo-stabilization efficiency of these Schiff bases, for the polystyrene, were investigated. The alterations in the infrared spectrum, surface shape and the weight loss post of the light exposure to radiation were tested. This observation shows that the carbonyl group resulting from chain decomposition and the weight loss of (PS) was reduced comparing to the pure polystyrene. The results indicate that these Schiff's bases posse a high effect in absorbing UV light, removing radicals, reducing HCl, and forming peroxides, can be used as photo-stabilizing for the PS films.