A new polystyrene foam for food packaging offers accelerated degrading with no loss of performance while in use, its manufacturer claims.
Polystyrene is extensively used as food packaging because of its low cost and insulating properties.
However regulatory and consumer pressure to reduce the impact of packaging waste have been forcing processors to seek more environmentally-friendly alternatives.
Canadian firm Cascades claims its Bioxo oxo-degradable polystyrene foam containers break down within three years, with no loss of performance while used as a packaging material.
Conventional polystyrene containers can take hundreds of years to break down, although the process can be accelerated considerably using chemicals and other methods. These, however, are costly both costly and cause further environmental damage.
Bioxo uses totally degradable plastic additives (TDPAC), developed by Canadian polymer additives supplier EPI. The additive, mixed with the base resin acts as a catalyst to promote degradation, without compromising performance while the material is used as a package, the manufacturer claims.
After use, the foam degrades through exposure to oxygen, heat and ultra-violet light or mechanical stress into a fine powder. Once broken down, bacteria and other micro-organisms can digest the powder.
The breakdown process will release carbon dioxide into the atmosphere and so while the shortage of landfill space may be alleviated, the solution will inevitably add to the problems of greenhouse gas emissions.
Bioxo has been approved for use as a food contact material by both Canadian and US regulators. All Bioxo products will feature a label to inform consumers that they are using a container that degrades.
Cascades' production sites across the US, Europe and Asia manufacture several hundred million food containers each year. The company claims to be the first to commercially develop CFC-free polystyrene foam in 1988.
Some estimates suggest that the UK alone sends 300,000 tons of polystyrene waste to land fills sites each year. With land fill capacity filling up, and the rising costs of discarding waste rising, packaging materials that degrade are one possible solution to these problems.