SHAPE SHIFTING POLYMER PLASTIC

Researchers have invented a new plastic material that can change into three different shapes based on heat. The chemical engineers from MIT and the Helmhotz Association of German Research Centers demonstrated a plastic tube with three "programmed" diameters (4.5 mm, 6.9 mm, 5.8 mm) that are selected by altering the temperature.

From the MIT News Office:
An "intelligent stent" made of the new class of plastics could assume three different shapes to facilitate medical procedures: It would assume a handy oval shape for insertion, then a fully inflated round shape for temporary use inside a blood vessel, duct or other cylindrical organ, and lastly, a compressed cylindrical shape for easy removal.

The triple-shape-shift from shape A to B to C could also have applications in industry. In factories, changeable plastic fasteners could be implanted in, or attached to, one part, then heated to extend an arm to another part. With further heating, the fastener would change shape yet again to lock itself in place. In effect, it would be an automated form of self-assembly.

via boing boing