The Polymer Waste Problem

Equally important although not publicised at the time was the accumulation in large dumps of discarded vehicle tyres. These are in fact much more persistent in the environment than plastics and secondary uses have been traditionally found for a proportion of discarded tyres, ranging from impact absorbing buffers on boats and docks, to recreational usage in childrens play areas. Durability has been turned to advantage in these secondary applications of used tyres but in practice they utilise only a small fraction of the polymer wastes and a major proportion of discarded tyres ultimately end up in landfill. 

End-use kT Percentage by weight Percentage of plastics in total waste 

Source Association of Plastics Manufacturers in Europe, APME. 

Over 16 million tons of post-user plastics waste is produced in Western Europe every year and more than half is produced by households (Table 4.1). Although many items of packaging are re-used at least once (notably carrier bags and bottles), this does little to reduce the burden on the municipal waste collection systems. The source of packaging waste is not always clear in published statistics. Stretch-wrap film used for packaging hay is not classified as agricultural waste nor does it appear as industrial waste but it is a severe pollution problem for the farmer and a visual blight in the countryside. 

By contrast, relatively uncontaminated single polymer types can be collected from retail outlets by segregation on site [e.g. discarded polypropylene crates, battery cases and supermarket shrink-wrap). These can be recycled with the addition of new antioxidants and UV stabilisers into the primary application, generally as a blend with virgin polymer, without significant loss of mechanical properties. 

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