The logic of renewable plastics is being taken a step further, with innovators from Tetra Pak to Coca-Cola making progress in using plant-derived high density polyethylene (HDPE) and polyethylene terephthalate (PET) in their packaging.
Unlike bioplastics such as polylactide (PLA), which do not always share the processing and performance characteristics of traditional polymers, Tetra Pak emphasises the fact that its 'Green PE' is just that. It is produced by Brazilian petrochemical company Braskem from ethanol extracted from sugar cane.
Unlike most other biopolymers, it can be recycled together with synthetic plastics.
Braskem is currently building the world's first commercial-scale PE plant in the south of Brazil, and aims to start supplying Tetra Pak and other customers in early 2011. The carton company will use volumes of just 5,000t a year for its caps and closures.
Director of forestry and recycling Mario Abreu said: "We hope this agreement with Braskem will encourage increased investment in Green PE and, therefore, more available supply. This will enable it to become economically viable for industry."
Currently, the plan is to use the Braskem product for 5% of the company's HDPE demand, and price as well as availability is likely to determine whether that proportion increases.
During 2009, Braskem estimated that the cost of its cane-derived PE would be 50% higher than the oil-derived equivalent. Tetra Pak said it could not comment or speculate about pricing at this stage.
Meanwhile, Coca-Cola aims to produce 2bn of its PlantBottle plant-derived PET packs by the end of 2010. The bottles are already in use within markets in Denmark, western Canada and the western US.
Coca-Cola says the challenge will be moving from a 30% plant-derived PET bottle to a notional 100% plant-based bottle. No doubt a significant part of that challenge would again be cost.