Developments to Watch
A RECIPE FOR PLASTIC THAT'S MIGHTIER THAN STEEL
Here's a challenge: Try to make ordinary soda-bottle plastic stronger than steel. Researchers at the University of Massachusetts at Amherst say they have converted simple polyethylene into ultralight fibers that by weight are seven times stronger than steel. Polymer scientist Roger S. Porter says the fibers could be used in applications such as strong, lightweight doors for cars, bulletproof armor, inert surgical implants, and even sails for America's Cup yachts.
The key is the way the molecules are arranged. In ordinary polyethylene, they're randomly placed. But Porter reorganized the molecules so they are nearly perfectly aligned. That makes the fibers translucent, stiff, and light. Then, they can be woven or combined with other materials to make composites.
Porter used a dry extrusion process that doesn't require toxic solvents or other wet ingredients. So far, Du Pont Co. has patented part of that process, and other chemical companies are interested in manufacturing the superstrong fiber.EDITED BY WILLIAM D. MARBACH