Plastic doesn't grow on trees. But it may grow in plants--well, almost. In a project funded by the Energy Dept., scientists at Rensselaer Polytechnic Institute in Troy, N.Y., have developed a process to convert oil from vegetables, such as soybeans, into water-resistant plastic that sticks to materials like wood and aluminum.
"This is cost-effective," says Rensselaer chemist James Crivello, "as one doesn't have to rely on petroleum." Nontoxic, photosensitive salts developed at RPI are key to the process. The salts are added to chemically altered, or epoxidized, oil. When the mixture is exposed briefly to ultraviolet light, the salts produce an acid that catalyzes the conversion of the oil into solid plastic.
Crivello says the process could also be used to make coatings and adhesives from vegetable oils. Alcoa Laboratories is already testing a coating for lining aluminum food containers.