Clinton gets the vote for new bioplastics plant

Archer Daniels Midland Co. (ADM; Decatur, IL) will build a 50,000 tons/yr plant in Clinton, IA for production of polyhydroxyalkanoates (PHA) plastics based on technology developed by Metabolix (Cambridge, MA) for extracting and manipulating PHA, a natural polyester produced by many bacteria as a carbon storage material. This will be the first commercial plant for PHA natural plastics, with completion expected in mid-2008.

"We are pleased to announce Clinton, IA as the location for the first commercial plant to produce PHA-based plastics, which are renewable, biodegradable and suitable for multiple applications," said G. Allen Andreas, chairman, CEO and president of ADM, in a statement. "PHA natural plastics offer the global marketplace an alternative to traditional petroleum-derived plastics."

The PHA plant will be located adjacent to ADM''s wet corn mill in Clinton. The plant will utilize starch from the mill''s existing corn grind capacity as raw material for PHA production. In 2004, ADM and Metabolix announced a strategic alliance to commercialize Metabolix''s proprietary PHA technology. Early this year the companies announced they would build a commercial PHA plant.

PHAs have drawn interest from a number of corners, including at consumer goods giant Procter & Gamble, which developed its own PHAs under the Nodax brand name and reportedly planned to start a commercial scale, 40,000 ton/yr plant for PHAs this year. It is not clear if P&G has stopped Nodax development; the firm did not respond to questions before deadline.

Metabolix reports it can control PHA''s molecular bonding so that the material can be marketed with a broad range of properties and for applications including injection molding, film extrusion, and as fibers. Metabolix says grades already developed are available in molecular weights ranging from around 1000 to over one million. PHAs are thermally unstable above around 180°C, but Metabolix has developed techniques and formulations that allow PHA processing at elevated temperatures with minimal loss in molecular weight. Metabolix natural plastics have good heat resistance to hot liquids, according to the firm, so that PHA coated paper hot cups will handle coffee, soup and other hot liquids.