A novel photodegradable polyethylene-goethite (PE-goethite) composite film was prepared by embedding the
goethite into the commercial
polyethylene. The degradation of PE-goethite composite films was investigated under
ultraviolet light irradiation. The photodegradation activity of the PE
plastic was determined by monitoring its
weight loss, scanning
electron microscopic (SEM) analysis and
FT-IR spectroscopy. The weight of PE-goethite (1 wt%) sample steadily decreased and
led to the total 16% reduction in 300 h under
UV-light intensity for 1 mW/cm(2). Through SEM observation there were some cavities around the
goethite powder in the composite films, but there were few changes except some surface chalking phenomenon in pure PE film. The degradation rate could be controlled by changing the concentration of
goethite particles in PE
plastic. The degradation of composite
plastic initiated on PE-goethite interface and then extended into
polymer matrix induced by the
diffusion of the
reactive oxygen species generated on
goethite particle surface. The
photocatalytic degradation mechanism of the composite films was briefly discussed.
