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Bistable [c2] Rotaxanos de la cadena de las margaritas como actuadores reversibles parecidos a los músculos en geles
Antoine Goujon1, Thomas Lang1, Giacomo Mariani2
1SAMS Research Group, Institut Charles Sadron, University of Strasbourg, CNRS , 23 rue du Loess, BP 84047, 67034 Strasbourg Cedex 2, France.
Journal of the American Chemical Society
|October 13, 2017
Resumen
Los investigadores desarrollaron máquinas moleculares sensibles al pH en la ciencia de los polímeros. Estos geles de polímero se contraen y se expanden significativamente, lo que demuestra una activación molecular sincronizada para los materiales activos.
Área de la Ciencia:
- Ciencias de los Polímeros
- Ciencias de los materiales
- Nanotecnología
Sus antecedentes:
- Las máquinas moleculares ofrecen potencial para la transferencia de movimiento a nanoescala a macroscala en dispositivos activos.
- Los sistemas eficientes requieren la exploración de los aspectos termodinámicos y topológicos para la producción de trabajo útil.
Objetivo del estudio:
- Para describir la polimerización ramificada de los rotaxanos de cadena margarita [c2] biestables sensibles al pH.
- Para investigar la activación macroscópica de los geles de polímero resultantes basados en el comportamiento de la unión mecánica.
Principales métodos:
- Se utilizó la cícloadición Huisgen 1,3-dipolar catalizada por cobre (química de clic) para la polimerización.
- Caracterizó los geles químicos utilizando la resonancia magnética nuclear de protones de giro de ángulo mágico de alta resolución (HR-MAS 1H NMR) y los experimentos de dispersión de neutrones.
Principales resultados:
- Se han sintetizado con éxito geles poliméricos reticulados a partir de rotaxanos de cadena de margarita [c2] bistables sensibles al pH.
- Se han demostrado cambios de volumen significativos (aproximadamente del 50%) en los geles químicos en respuesta a las variaciones del pH (estado de protonación).
Conclusiones:
- Los cambios de volumen macroscópicos en los geles son impulsados por la activación sincronizada de enlaces mecánicos a nivel molecular.
- Este trabajo contribuye al desarrollo de materiales y dispositivos activos a través del movimiento controlado de máquinas moleculares.
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