From University of Illinois at Urbana-Champaign
African plant can be grown in Illinois, shows promise as wood substitute
CHAMPAIGN, Ill. — Samples of potential wall-sheathing, sub flooring, tiles and interior car panels are seen throughout Poo Chow’s Wood Engineering laboratory at the University of Illinois. The samples, however, are not made of traditional wood fiber; they contain varying blends of plastic both virgin and recycled combined with kenaf pronounced kuh-NAFF, cornstalks or corncobs.
Chow, a professor of wood science, is experimenting with non-wood fiber crops to show that it is possible to make high-quality products and reduce the demand for fibers harvested from trees. Corn is a primary crop in Illinois, but a new use for it would add yet more value. Kenaf is new to the state – grown only by Chow and Robert J. Lambert, a UI professor emeritus of crop science – but it could be a viable, alternative income-producing crop in Illinois, Chow said.
What is missing, however, is industry demand for its fibers, which replace wood in products made in parts of Africa, Europe and Asia. Chow’s initial research on kenaf, a plant native to east-central Africa, already has helped to improve Texas-grown crops that find their way into newsprint.
A need for non-wood fibers is approaching, Chow said. Each American uses some 700 pounds of paper a year. The U.S. paper industry alone produces more than 200,000 tons of paper and paperboard daily, using natural fibers called cellulose taken from wood such as fir, pine and oaks.
Chow is urging Illinois farmers to consider using small portions of set-aside land to experiment with kenaf to broaden the state’s knowledge base, “so when the market is ready, we’ll be ready.” Kenaf grows quickly, up to 10-15 feet high, into a forest of narrow poles and leaf-colored branches. Yields per acre on a test plot in Southern Illinois have been as much as 7 tons of dry fiber.
“Growing kenaf lets you produce a fiber similar to that made from wood, but you can do it in 150 days,” he said. “Compare that with the time it takes to plant and grow a tree to maturity. We know how to grow kenaf in Illinois. You don’t have to buy new equipment, just modify existing machinery.”
The research – led by Chow, Lambert and J.A. Youngquist of the USDA Forests Products Laboratory in Madison, Wis. – is part of a value-added project funded by the Illinois Council for Food and Agricultural Research and the USDA Forest Service. Their findings have garnered attention worldwide.
At the Third Annual American Kenaf Society Conference in Texas early last year, Chow detailed optimum conditions for four varieties of kenaf. In October, at the 2000 International Kenaf Symposium in Japan, he told how he has combined kenaf fiber and recycled plastics to produce thermoplastic composites for construction panels, interior automobile parts, plastic floor tiles and plastic lumber.
In December, at the Fifth Pacific Rim Bio-Based Composites Symposium in Australia, Chow described how he used an injection-molding process with a blend of 40 percent cornstalk and 60 percent polypropylene plastic. The quality matched that of similar items made of pine and demolition wood.