Scientists have produced a new kind of rubbery plastic similar to the rubbers used in adhesives and shoe soles, according to research results reported this week at a meeting of the American Chemical Society in San Diego. The novel material, formed from two common petroleum products, promises production costs considerably lower than those of comparable polymers.

Geoffrey Coates of Cornell University and his colleagues made the discovery quite by accident, happening on a catalyst that enables the formation of a polymer from the inexpensive petroleum products, ethylene and polyethylene. Similar polymers are made from the relatively expensive chemicals styrene and butadiene through what is termed a "living polymerization process," in which hard and soft monomer blocks are strung together to yield an elastic material. Researchers had long thought that such a polymerization process should be possible for these cheaper petroleum products, but the proper catalyst eluded them. The identification of this new titanium-based catalyst by Coates's team now brings that search to an end.

As to why scientists didn't figure this out sooner, Coates remarks, "There is no way to rationally predict the action of compounds. We simply stumbled across this, luckily with our eyes open."