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Bistable and photoswitchable states of matter.

ABSTRACT: Classical materials readily switch phases (solid to fluid or fluid to gas) upon changes in pressure or heat; however, subsequent reversion of the stimulus returns the material to their original phase. Covalently cross-linked polymer networks, which are solids that do not flow when strained, do not change phase even upon changes in temperature and pressure. However, upon the addition of dynamic cross-links, they become stimuli responsive, capable of switching phase from solid to fluid, but quickly returning to the solid state once the stimulus is removed. Reported here is the first material capable of a bistable switching of phase. A permanent solid to fluid transition or vice versa is demonstrated at room temperature, with inherent, spatiotemporal control over this switch in either direction triggered by exposure to light.

SUBMITTER: Worrell BT

PROVIDER: S-EPMC6052001 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Bistable and photoswitchable states of matter.

Worrell Brady T BT McBride Matthew K MK Lyon Gayla B GB Cox Lewis M LM Wang Chen C Mavila Sudheendran S Lim Chern-Hooi CH Coley Hannah M HM Musgrave Charles B CB Ding Yifu Y Bowman Christopher N CN

Nature communications 20180718 1

Classical materials readily switch phases (solid to fluid or fluid to gas) upon changes in pressure or heat; however, subsequent reversion of the stimulus returns the material to their original phase. Covalently cross-linked polymer networks, which are solids that do not flow when strained, do not change phase even upon changes in temperature and pressure. However, upon the addition of dynamic cross-links, they become stimuli responsive, capable of switching phase from solid to fluid, but quickl ...[more]

PMID: 30022053

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