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Transformación morfológica macroscópica fotoinducida de un conjunto de diarileteno anfifílico: movimiento dinámico

Kenji Higashiguchi¹, Genki Taira, Jun-ichiro Kitai

¹Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University , Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan.

Journal of the American Chemical Society

|February 5, 2015

Resumen

Las microestructuras de diarileteno anfifílico cambian de forma de forma reversible entre las esferas y las fibras cuando se exponen a cambios de luz o temperatura. Este movimiento mecánico fotoinducido es útil para diseñar fotoactuadores avanzados.

Área de la Ciencia:

Ciencia de los materiales Ciencia de los materiales.
Química supramolecular de las moléculas.
La fotoquímica es la fotoquímica.

Sus antecedentes:

Las moléculas anfifílicas se autoensamblan en varias microestructuras.
Los diariletenos se someten a fotoisomerización reversible, cambiando de color y estructura al exponerse a la luz.
El control de las microestructuras con estímulos externos es crucial para los materiales avanzados.

Objetivo del estudio:

Para investigar los cambios morfológicos reversibles fotoinducidos de las microestructuras autoensambladas de diarileteno anfifílico en agua.
Comprender el mecanismo de la transformación morfológica entre las microsferas y las fibras.
Para explorar el potencial de este sistema para aplicaciones de fotoactuadores.

Principales métodos:

Síntesis de un diarileteno anfifílico con grupos de alquilo y trietilenglicol.
Caracterización de microestructuras autoensambladas utilizando microscopía óptica polarizada (POM), microscopía electrónica de transmisión (TEM) y difracción de rayos X (XRD).
Investigación de los cambios morfológicos inducidos por la luz y la temperatura.

Principales resultados:

Las microestructuras de diarileteno autoensambladas exhibieron transformaciones morfológicas reversibles entre las microesferas incoloras y las fibras coloreadas provocadas por los rayos UV y la luz visible.
Los cambios morfológicos también se observaron con variaciones de temperatura, lo que indica una transición de fase.
Los análisis microscópicos y de difracción detallados revelaron el proceso dinámico de formación de fibras y restauración de la esfera.

Conclusiones:

El sistema diarylethene anfifílico demuestra un cambio morfológico reversible fotoinducido único.
El comportamiento observado puede interpretarse como una transición de fase controlada por la luz y la temperatura.
Este estudio proporciona información valiosa para el diseño de fotoactuadores sofisticados basados en movimiento mecánico fotoinducido.

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