Golden foam blankets nuclear radiation.

Golden foam blankets nuclear radiation

Chemists and business executives have long known there's gold in chemical polymers, but until recently that has only been figuratively true. Now John Fackler of Texas A&M University in College Station has invented a polymer foam that holds molecules of gold suspended in it. The remarkable yellow metal's ability to absorb the scatter atomic particles could make the foam useful as a lightweight shield in areas with high nuclear radiation, Fackler says.

Gold is held in the foam by binding to the carbon atoms in chains of polyethylene. It wasn't easy to get the gold suspended in the polymer, but Fackler had very limited choices in what metal to use because gold is one of the few nonradioactive metals heavy enough to scatter nuclear radiation, he says. Platinum, mercury, thallium and bismuth can also do the job, but each has problems: Platinum oxidizes too easily, mercury is toxic, thallium is carcinogenic and bismuth won't bind readily to the carbon in polyethylene, Fackler says.

The foam, white and about the density of Styrofoam, can also be shaped into mirrors or lenses for particle accelerators or fabricated into lightweight protective clothing for people working in radioactive environments, Fackler says. Gold's excellent electrical conductivity also makes the polymer potentially useful as lightweight battery electrodes or electrical heating elements for de-icing aircraft wings, he adds.