摘要 |
Certain polymer materials, including perfluorosulfonic acid ionomers, have been found to be capable of being deformed from an initial permanent shape into three or more temporary shapes. An article thus formed from such a polymer material may be used initially in a final temporary shape. As the article is progressively heated, the polymer composition reverts successively from its final temporary shape through its intermediate temporary shapes. If a suitable temperature is reached, the original permanent shape is recovered. The article may be devised to serve successive functions in each of its several shapes.
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