Plants today, auto parts tomorrow

InTech, Oct 2001

East Lansing, Mich.-Plants and agricultural products may someday rule as Michigan State University (MSU) researchers find ways to use them to make tough, lightweight, and versatile materials that manufacturers can fabricate into automotive parts, tennis rackets, housing panels, furniture, or even bridges.

"There is a growing acceptance that there have to be more environmentally friendly processes and products," said Lawrence Drzal, director of the Composite Materials and Structures Center at MSU."But consumers aren't going to accept products based only on environmental considerations; these products must perform and be cost effective to be competitive."

Biocomposites are gaining acceptance in everything from automotive manufacturing to bridge building because they are stronger and cheaper to make than traditional plastic and glass fiber. These "green" composite materials turn fibers from plants such as cotton, jute, kenaf, flax, or hemp and plastics from soybean, wastepaper, corn, and sugar into lightweight, strong, and stiff materials.

Biocomposite materials, Drzal said, have several advantages. Because they are renewable based, biocomposites would reduce dependency on petroleum. The cost for composite materials can drop with large-scale usage. Potential harmful effects related to materials processing and disposal can be reduced, as there is potential for biodegradability. MSU researchers at the center are successfully developing and designing bioplastics, as well as new methods for making them economically.

Natural fibers have significant advantages over glass fibers as reinforcements in composite materials, Drzal said. Natural plant fibers, extracted, cleaned, and product ready, cost roughly 25 cents vs. 75 cents per pound for glass fiber. Natural fibers have several advantages over traditional glass fibers, including low cost, low density, acceptable specific strength and stiffness, enhanced energy recovery, carbon dioxide sequestration, and biodegradability.

The environmental impact is significant beyond the landfill.The high-fiber plants commonly used for composites are easily grown, require few pesticides, and rotate with traditional food crops.