Plastic Waste Based on Mass Full Carbon Backbone Polymeric Materials-On the Way to Bio-recycling to Value Added Polyesters.Author(s): Emo Chiellini
Commodity plastic items based on fossil fuel mass polymeric materials such as polyethylene (PE), polypropylene (PP) and Polystyrene (PS)have gradually become an integral part of our daily life in the plastic age and it is almost impossible to get rid of them due to their numerous applications in a wide range of human activities. It is however to take into account that inappropriate disposal at the end of their service life gives raise the several environmental consequences bound to their structural recalcitrance to biodegradation in different terrestrial and aquatic environmental compartments. Standing the wide expertise accrued over the years by the research group I was leading at the University of Pisa [1-3] on the structural behaviour held by PE and PP polymeric materials and relevant plastic items loaded with tiny amount (0.5–1% wt) of pro-oxidant /pro-degradant additives at the end of their service life upon controlled thermal and/or UV exposure a breakthrough wasreached in the biodegradation in soil and acquatic environmental compatment (fresh, brackish and salty waters) of the oxidatively fragmented plastic items based on Pe and PP. Recently in cooperative activities established with English and Polish research groups [4-6] within the undertaken ambitions goal bond to an Environmental Cleaning Mission, intriguing results have been reached on the bioconversion of the oxidatively fragmented plastici tems based on PE,PP and PS polimeric materials, to polyhydroxyalkanoates (PHAs) by selected microbial strains. It is taken for granted that plastic items treated with pro-oxidant /pro-degradant additives, wherever would be inappropriately released in the environment, they should be oxidatively fragmented in a relatively reasonable time frame and become appetible for environmental ubiquitary microbial strains with conversion under aerobic conditions into water ,carbon dioxide, cell biomass and eventually to environmentally harmless PHAs.