Photo-re-stabilisation of recycled post-consumer films from greenhouses

The photo-oxidation behaviour of recycled post-consumer films from greenhouses has been studied in order to evaluate the environmental resistance of these secondary materials and the effect of some stabilising agents. The presence of the UV absorber slows down the weathering of the post-consumer materials. After about 1000 h of accelerated weathering the unstabilised post-consumer material becomes brittle, while the re-stabilised post-consumer film becomes fragile only after about 1500 h. A synergistic effect is observed when an antioxidant and an UV stabiliser are added. Indeed, in this case, the recycled material is not brittle even after more than 1700 h. These last results can be probably correlated to the protective action of the antioxidant that avoids the formation of oxygenated compounds during the processing.