New Plastic Conducts Heat Better Than Metals, But Only in One Direction
Polymers are generally put to work as insulators, but a team of researchers at MIT has devised a way to turn polyethylene -- the most commonly used polymer -- into a conductor that transfers heat better than many pure metals. But the conversion of insulator to conductor is only half of the breakthrough; by coaxing all the polymer molecules into precise alignment, the researchers have created a polyethylene that conducts heat in only one direction. The plastic material remains an electrical insulator. Getting a bunch of polymer molecules to fall in line is no easy task -- left to their own devices, the molecules will settle into a chaotic arrangement that is resistant to heat transfer. But the MIT team found that by drawing polyethylene fibers slowly out of a solution they could get the molecules to line up facing the same way, creating a material that will let...