Monday, September 19, 2005

"MATERIALS: Inventor's 'recipe' makes polymers conductive"

A new type of conductive polymer created at Integral Technologies Inc. promises to offer a plastic material that can be used as a substitute for metal. While today's conductive polymers are more flexible and weigh less than metal, their higher impedance has made them suitable only for low-voltage, low-current applications. When polymers are doped enough to support high-current ac, for instance, they become too brittle. Now Integral Technologies (Bellingham, Wash.) claims to have melded polymers with micron-sized metal filaments to create a material with properties that are the best of both worlds, to form anything from copper wires to flexible interconnects to antennas. "Ours is the world's only highly conductive polymer," claimed Thomas Aisenbrey, inventor of the material and general manager and vice president of product development at Integral. "It's conductive enough that you can run heavy current through it, either ac or dc." Called ElectriPlast, the approach is derived from a material called Plastenna that Aisenbrey engineered to make moldable antennas for wireless telephone handsets. The company embedded metal filaments in the handsets' case to gather RF signals. Then it broadened the recipe for the material, so that now its process can be used to make nearly any currently available polymer conductive.