Plastics made from oranges

A Cornell University research group has made a sweet and environmentally beneficial discovery -- how to make plastics from citrus fruits, such as oranges, and carbon dioxide. In a paper published in a recent issue of the Journal of the American Chemical Society (Sept. 2004), Geoffrey Coates, a Cornell professor of chemistry and chemical biology, and his graduate students Chris Byrne and Scott Allen describe a way to make polymers using limonene oxide and carbon dioxide, with the help of a novel "helper molecule" -- a catalyst developed in the researchers' laboratory.

By using their catalyst to combine the limonene oxide and CO2, the Coates group produced a novel polymer -- called polylimonene carbonate -- that has many of the characteristics of polystyrene, a petroleum-based plastic currently used to make many disposable plastic products.

The Coates research team is particularly interested in using CO2 as an alternative building block for polymers. Instead of being pumped into the atmosphere as a waste product, CO2 could be isolated for use in producing plastics, such as polylimonene carbonate.