Abstract:
Polyethylene (PE), in common with other plastics has a low tendency to degrade in the environment naturally and has the potential to harm the environment in a variety of ways. The polymer backbone in plastics is mainly composed of carbon and is utilized by microbes as an energy source, thus, bacterial degradation of plastic does occur in nature, albeit very slowly. There have been some developments in this field but the so-called ‘biodegradable’ plastics have yet to make their mark.
Plastic degradation in the environment also takes place through interaction with sunlight and the process can be accelerated by the addition of a photocatalytic agent such as titanium dioxide TiO2, commonly known as ‘titania’. Thus, incorporation of titania nanoparticles (TNPs) in polyethylene has proved to be very effective and when the titania nanoparticles used are doped with suitable metals, the photocatalytic degradation occurs very fast even in the sunlight. It was hypothesized, therefore, that the titania embedded polyethylene films, upon light exposure, would break into smaller fragments, which could be easily degraded by the indigenous bacteria at an accelerated rate. The aim of this research was to develop polyethylene films that would be ‘photo biodegradable’. In order to enhance the photocatalytic efficiency of the tiatania nanoparticles, these were modified with composites of visible light active photocatalyst (e.g. Ag3PO4).
