Talk about agility. Researchers at the Massachusetts Institute of Technology and the Helmholtz Association of German Research Centers say they have invented a new class of materials that can assume three different shapes depending on how much heat is applied.
"Triple-shape materials can switch from shape A, then to shape B, and on to shape C," explains polymer chemist Andreas Lendlein of the Helmholtz Institute, who developed the materials with MIT chemical engineer Robert Langer. "Using two, rather than just one, shape changes offers unique opportunities for applications such as 'intelligent' stents or 'smart' fastener systems." Intelligent stents, for example, could assume an oval shape for insertion, a round shape for use and a compressed shape for removal. In previous collaborations, Langer and Lendlein invented a dual-shape class of materials used to create a 'smart' suture, and a plastic that changes shape with light.