The effect of nanoclay on photo-oxidation of polyethylene

Increasing environmental concerns about plastic waste in the community has led to the development of environmental friendly polymeric packaging materials. Polyethylene, one of the widely used packaging materials, can be made biodegradable by blending with biopolymers such as starch and/or pro-oxidants which are metal complexes (e.g. cobalt stearate, cerium stearate). Recent studies on polyethylene degradation have found that addition of nanoclay, which is used as filler in polymer composites mainly to enhance their mechanical properties, also increases their photo-oxidative degradation. The present study investigates the photo-degradation of low density polyethylene (LDPE) formulated with nanoclay and evaluates the effect of nanoclay concentration on the overall photo-oxidation process. Photo-oxidative aging of polyethylene and its nanocomposites were carried out in a QUV weathering tester for a maximum period of two weeks. The degradation progress was followed by monitoring the physical and chemical changes of the samples using tensile tests, Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The results indicate that the incorporation of nanoclay significantly enhances the degradation of polyethylene.