Even though biodegradable plastics made of renewable raw materials are nowadays readily available, there is still no sign of major tonnages hitting the market. But things could well change soon: Cargill Dow Polymers LLC (CDP, 2030 Abbott Road, Midland, MI 48674/USA), the 50:50 joint venture of Cargill Inc. and The Dow Chemical Company, is investing “several hundred million USD” in the industrial-scale production of polylactic acid (PLA) materials. This is the material that was used, for example, for Danone´s degradable yoghurt cups. Until now, the production capacity for PLA has been a meagre 4,000 t/y.

Using what it calls a “revolutionary technology” called “NatureWorks”, CDP intends to start up a new plant in Blair, Nebraska, USA, at the end of 2001 with a capacity of 140,000 t/y. In the United States, maize is used as the basic raw material, but in principle, any plant which stores starch or sugar can be used. In Europe, this would be wheat or sugar beet, and in Asia, rice. According to press reports, the material will initially be offered at a price of USD 1-2/kg, with a downward tendency in the longer term. As a result, the material would also be able to compete on cost terms with conventional polymers in the foreseeable future.

The PLA material aims to secure market share quickly, particularly in the packaging industry. CDP´s marketing activities will initially focus on three specific areas of packaging: high-grade film, thermoformed food and drink packs, and coatings for cardboard and paper. In fibre form, the material is also suitable for the production of textiles (garments, carpets).

Cooperation agreements have already been signed with a number of users, says CDP. Tetrapack, Trespaphan GmbH, the British Autobar Group Ltd, Mitsubishi Plastics and Woolmark Company Ltd are just a few of the companies that are said to have committed themselves to the development of products made of “NatureWorks”.