A new polystyrene–TiO2 nanocomposite film and its photocatalytic degradation

A new kind of photodegradable polystyrene (PS)–TiO 2 nanocomposite film was synthesized. The TiO 2 nanoparticles were first modified by grafting polymer on its surface (G-TiO 2 ), and then the PS–G-TiO 2 composite films were formed through polymerization. The photocatalytic degradation of the composite films was investigated. The as-prepared films were characterized by scanning electron microscope (SEM), gel permeation chromatogram (GPC), FT-IR and UV-Vis spectroscopy, and the photoinduced weight-loss. The results show that PS–G-TiO 2 nanocomposite films could be efficiently photocatalytically degraded under UV illumination in air. The weight-loss of the PS–G-TiO 2 film reached 29%; the average molecular weight reduced to 1/4 of the original molecular weight under UV-light irradiation for 300 h, implying that some benzene rings had been cleaved. The photocatalytic degradation mechanism of the films is briefly discussed.