Photo-responsive and thermoreversible networks from the self-assembly of azobenzene-containing liquid crystal triblock copolymers
Abstract
We report the synthesis of azobenzene-containing coil-liquid crystal-coil triblock copolymers that can serve as mechano-optic actuators for applications that include non-invasively steering fiber optics. The coil (polystyrene) end-blocks phase segregate from the liquid crystal midblock forming of uniform and uniformly-spaced physical crosslinks, resulting in highly reproducible and thermoreversible networks by self-assembly. These polymers are elastic in the melt (at room temperature) and can be easily spun, coated or molded. Mechanical stretching results in a temporary monodomain alignment. Starting from identical triblock prepolymers (with polystyerene end blocks and 1,2-polybutadiene midblocks), a matched pair (azobenzene-containing, and non-azobenzene-containing) of liquid crystal triblock copolymers was synthesized. These triblocks were then be blended to prepare a series of elastomers with 0 to 5% azobenzene groups, while matching in nearly all other physical properties (cross-link density, modulus, birefringence, etc.), allowing the effect of concentration of photo-responsive groups to be unambiguously determined. Results will be presented that demonstrate this approach to independent control of optical density and photo-mechanical sensitivity.
Additional Information
© 2016 Society of Photo-optical Instrumentation Engineers (SPIE).Additional details
- Eprint ID
- 88146
- Resolver ID
- CaltechAUTHORS:20180723-155342466
- Created
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2018-07-24Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field
- Series Name
- Proceedings of SPIE
- Series Volume or Issue Number
- 9939