Plastics from Corn? Dow and Cargill Will Investigate
Dow Chemical Co. (Midland, Mich.) and Cargill (Minneapolis, Minn.) have announced the formation of Cargill Dow Polymers LLC, a 50/50 limited liability company, to develop and market polylactic acid (PLA) polymers. Based on polylactic polymer technology, PLA polymers are an entirely new polymer family derived from renewable agricultural resources, such as corn or sugar beets. Cargill currently produces the polymers for biodegradable applications; the new company will pursue applications in packaging, films, fibers and others.
"PLA resins represent an enhancement to the polymer product portfolio available to customers today," said Kathleen Bader, vice president, polystyrene, at Dow. "Their range of applicability crosses applications served by many alternative polymers today."
"Working with Dow greatly expands the opportunities for PLA resins and applications," said Pete Hawthorne, general manager, emerging businesses, Cargill. "Cargill brings process technology and a low cost manufacturing position for lactic acid and PLA resins, as well as a strong patent portfolio of critical technology. Dow's world class polymer science, applications technology and access to a global customer base will help accelerate the commercialization of these new materials," Hawthorne said.
The LLC's formation follows a successful 15-month joint development program during which Cargill and Dow combined efforts to evaluate the potential for PLA polymers and the benefits of jointly pursuing PLA product development and marketing. Key application areas targeted for PLA polymers include cast films, fibers and non-wovens, blown films, rigid containers and paper/board coatings. "Polylactic acid technology has the potential to provide a new product platform to compete with hydrocarbon-based thermoplastics," said Jim Stoppert, Dow global director, issues and development, polystyrene, who has been named president of the LLC. Cargill Dow Polymers will be managed by a team of employees from both Cargill and Dow. If all goes well initially, staffing could exceed 100 within the first year.
In some cases, PLA polymers will displace certain hydrocarbon-based polymers, such as polyethylene, polystyrene and polypropylene. "In other cases," Stoppert added, "PLA polymers will be used to develop applications that are currently non-plastic. The exciting aspect of this product is the opportunity to work with customers who value the unique properties of PLA resins and can commit the time and resources required to bring new applications to market."
Cargill Dow Polymers will manufacture PLA resins at the former Cargill semi-commercial plant near Minneapolis. Current 8-million lb/yr PLA capacity will be doubled by the end of 1998. This volume, says Pat Gruber, a Cargill VP who will also manage the joint venture, will be sufficient to test customer applications. A worldscale plant could be in the works by 2001.
A Polymer for the Future
PLA resins are composed of chains of lactic acid, a natural food ingredient which can be produced by converting starch into sugar and then fermenting it to yield lactic acid. Water is then removed to form lactide, which is converted into PLA resins using a solvent-free polymerization.
PLA polymers offer a broad balance of functional performance which makes them suitable for a wide variety of market applications. They are expected to compete with hydrocarbon-based thermoplastics on a cost/performance basis. PLA polymers provide good aesthetics (gloss and clarity) and processability similar to polystyrene. PLA polymers also exhibit tensile strength and modulus comparable to some theremoplastics. Like PET (polyethylene terephthalate), these polymers resist grease and oil, and offer good flavor and odor barrier. PLA polymers also provide for heat sealability at lower temperatures than polyolefin sealant resins. The polymers can be processed by most melt fabrication techniques including thermoforming, sheet and film extrusion, blown film processing, fiber spinning and injection molding.
Cargill Dow Polymers will continue to manufacture EcoPLA Renewable Biopolymers, a PLA polymer, at the semi-commercial facility near Minneapolis. "EcoPLA biopolymers have been targeted primarily at biodegradable applications," said Gruber. This material biodegrades completely and safely into carbon dioxide and water when composted in municipal or industrial facilities. "While the current market for biodegradables offers many opportunities for growth, the new company will enable us to further promote the use of renewable resources in a broad range of applications," Gruber added.
Cargill has invested significantly in PLA polymers since the late 1980s and brings to the LLC a broad patent portfolio that will be enlarged by the LLC. Dow also has made a major investment during the joint development program to evaluate the potential of this polymer family. Through the LLC, both companies will leverage their respective intellectual and technical assets to accelerate product application and market development.
Cargill is an international marketer and processor of agricultural, food, financial and industrial commodities with 79,000 employees at more than 1,000 locations in 72 countries. The company's sales were $56 billion in fiscal year 1996-1997.
The Dow Chemical Company is the fifth largest chemical company in the world with annual sales of more than $20 billion. Dow manufactures and supplies chemicals, plastics, energy, agricultural products, consumer goods and environmental services for customers in 157 countries around the world, and employs approximately 40,300 people worldwide.
For more information about PLA polymers from Cargill Dow Polymers, in the United States or Canada, contact the Dow Customer Information Group at 800-441-4369; in Europe contact the Dow Information Center in the Netherlands at 31-20-691-6268. For more information in Japan, call Akira Kumatori of Cargill Japan Ltd. at 81-33-285-0824. In other regions, contact the local Dow or Cargill business office.