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Cambio reversible fotoinducido de la viscosidad del fluido
Hideki Sakai1, Yoichi Orihara, Hideki Kodashima
1Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan. hisakai@rs.noda.tus.ac.jp
Journal of the American Chemical Society
|September 30, 2005
Resumen
Los investigadores demostraron un cambio de viscosidad del fluido fotoinducido reversible. La adición de un tensioactivo fotointercambiable a una solución micelar alteró significativamente la viscosidad tras la exposición a la luz UV, con efectos totalmente reversibles.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Física es la química física.
- Ciencia de la coloide Ciencia de las coloides.
Sus antecedentes:
- Las soluciones micelares parecidas a gusanos exhiben una alta viscosidad debido a las redes entrelazadas.
- Las moléculas fotointercambiables pueden alterar las propiedades del material tras la irradiación de luz.
Objetivo del estudio:
- Investigar el efecto de un tensioactivo catiónico fotointercambiable modificado con azobenzeno en la viscosidad de las soluciones micelares de gusano.
- Para demostrar un cambio fotoinducido reversible en la viscosidad del fluido.
Principales métodos:
- Adición de bromuro de 4-butilozobenceno-4'-(oxieetil) trimetilamonio (AZTMA) a una solución de bromuro de cetiltrimetilamonio (CTAB) y salicilato de sodio (NaSal).
- Irradiación con luz UV para inducir la isomerización del AZTMA.
- Medición de la viscosidad de la solución antes y después de la irradiación.
Principales resultados:
- La solución inicial con trans-AZTMA exhibió una alta viscosidad debido a la formación de redes micelares.
- La irradiación de luz UV causó una disminución significativa en la viscosidad, atribuida a la interrupción de la red micelar por cis-AZTMA.
- El cambio de viscosidad fue totalmente reversible al cambiar entre los isómeros trans- y cis-AZTMA.
Conclusiones:
- Se logró con éxito un cambio de viscosidad del fluido fotoinducido reversible utilizando un tensioactivo fotointercambiable en un sistema micelar parecido a un gusano.
- Esto demuestra un nuevo método para controlar las propiedades de los fluidos con la luz.
- Aplicaciones potenciales en fluidos inteligentes y materiales sensibles.
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