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Shape-Persistent Actuators from Hydrazone Photoswitches.

ABSTRACT: Interfacing molecular photoswitches with liquid crystal polymers enables the amplification of their nanoscale motion into macroscopic shape transformations. Typically, the mechanism responsible for actuation involves light-induced molecular disorder. Here, we demonstrate that bistable hydrazones can drive (chiral) shape transformations in liquid crystal polymer networks, with photogenerated polymer shapes displaying a long-term stability that mirrors that of the switches. The mechanism involves a photoinduced buildup of tension in the polymer, with a negligible influence on the liquid crystalline order. Hydrazone-doped liquid crystal systems thus diversify the toolbox available to the field of light-adaptive molecular actuators and hold promise in terms of soft robotics.

SUBMITTER: Ryabchun A

PROVIDER: S-EPMC6346373 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Shape-Persistent Actuators from Hydrazone Photoswitches.

Ryabchun Alexander A Li Quan Q Lancia Federico F Aprahamian Ivan I Katsonis Nathalie N

Journal of the American Chemical Society 20190109 3

Interfacing molecular photoswitches with liquid crystal polymers enables the amplification of their nanoscale motion into macroscopic shape transformations. Typically, the mechanism responsible for actuation involves light-induced molecular disorder. Here, we demonstrate that bistable hydrazones can drive (chiral) shape transformations in liquid crystal polymer networks, with photogenerated polymer shapes displaying a long-term stability that mirrors that of the switches. The mechanism involves ...[more]

PMID: 30624915

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