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London, March 15 (ANI): A material commonly used in fuel cells can 'remember' up to three different shapes, and revert to each one at different temperatures, according to new research.
The new research unmasks the versatility of a new type of polymer, Nafion, reports New Scientist.
Tao Xie at General Motors in Warren, Michigan, twisted and stretched a Nafion strip into three distinct shapes, and found that it reverted to each shape at the appropriate temperature.
Nafion becomes softer as it is heated. At 140 degrees Celsius Xie stretched it into a particular shape, which was locked in the polymer's "memory" as it cooled to 107 degrees Celsius and stiffened.
Stretching and cooling it twice more allowed two other shapes to be memorised, so that when heated to the appropriate temperature the Nafion formed the corresponding shape.
Previously the best shape-memory polymers were able to remember only two shapes.
The study has been published in the journal Nature. (ANI)
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