Researchers at Aston University (Birmingham / UK; www.aston.ac.uk) have developed a biodegradable plasticiser that reduces the brittleness of films produced from PLA (polylactic acid) to enable them to be used in packaging applications such as carrier bags. Elongation to break is increased, typically from 5% to over 300%, and the tensile strength is also improved.

The plasticiser, based on a modified block copolymer formed between PLA and polyethylene glycol (PEG), needs to be biodegradable as it is likely to be introduced at volumes from 10-20%. Incorporation of the plasticiser appears also to accelerate the degradation of the PLA film and tests at the university showed the material disappeared completely in a composter within 20-25 days. The project has moved successfully from the laboratory to a commercial scale. It has been part-funded by the UK´s DTI (Department of Trade & Industry) and partners have included plastic bags and film supplier Europackaging (www.europackaging.co.uk).