Certain plastics known as shape-memory polymers switch to predetermined shapes when triggered by heat or light. Now, researchers have developed more-versatile versions of such polymers. When heated, each of the new triple-shape polymers switches to a second shape. Then, at a higher temperature, the plastic changes to a third form.
“For some applications, [these] more-complex deformations are required,” says chemist Andreas Lendlein of the GKSS Research Center in Teltow, Germany.