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Helicidad supramolecular controlada por la luz de una fase cristalina líquida utilizando un polímero helicoidal
Dirk Pijper1, Mahthild G M Jongejan, Auke Meetsma
1Department of Organic and Molecular Inorganic Chemistry, Stratingh Institute, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
Journal of the American Chemical Society
|March 14, 2008
Resumen
Los investigadores desarrollaron un polímero helicoidal controlado por la luz utilizando un nuevo interruptor molecular. Esto permite un control preciso sobre el polímero.
Área de la Ciencia:
- Química de Polímeros La química de los polímeros es la química de los polímeros.
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El control de la helicidad del polímero es crucial para los materiales avanzados.
- Los motores moleculares impulsados por la luz ofrecen mecanismos de control precisos.
- El poli (n-hexil isocyanato) (PHIC) exhibe estructuras helicoidales.
Objetivo del estudio:
- Desarrollar un sistema dirigible a la luz para controlar la helicidad del polímero.
- Para mejorar la inducción quiral en PHIC utilizando un interruptor molecular rediseñado.
- Para investigar la transmisión de información quiral al nivel supramolecular.
Principales métodos:
- Adhesión covalente de un interruptor molecular quiróptico al término PHIC.
- Utilizando isomerizaciones fotoquímicas y térmicas para el control quiral.
- Caracterización de la helicidad del polímero y las fases cristalinas líquidas.
Principales resultados:
- Mejoró significativamente la inducción quiral en PHIC.
- Control inducido por la luz y dependiente de la longitud de onda sobre la manipulación del polímero.
- Transmisión exitosa de la información quiral a una fase cristalina líquida colestérica.
Conclusiones:
- Un nuevo interruptor molecular quiróptico permite un control preciso de la luz sobre la helicidad del polímero.
- Este sistema permite un control total de la luz sobre el paso helicoidal de las películas de cristales líquidos.
- Demuestra una poderosa estrategia para el diseño de materiales quirales sensibles a la luz.
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