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Redistribución inducida por la fuerza de un equilibrio químico
Corissa K Lee1, Douglas A Davis, Scott R White
1Department of Materials Science and Engineering, Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|October 28, 2010
Resumen
Los mecanóforos de espiropirano en el poliuretano proporcionan una detección de estrés visual. Este estudio cuantifica la cinética del cambio de color y los cambios de equilibrio bajo tensión mecánica para aplicaciones de materiales inteligentes.
Área de la Ciencia:
- La ciencia de los polímeros es la ciencia de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- Mecanoquímica es la mecanoquímica.
Sus antecedentes:
- Los mecanóforos de espiropirano (SP) permiten la detección del estrés visual en los polímeros.
- Estos mecanóforos tienen el potencial de crear materiales inteligentes con capacidades de auto-detección.
- Se logró la incorporación al poliuretano a través de la polimerización de crecimiento gradual.
Objetivo del estudio:
- Para investigar la cinética de la respuesta mecanoquímica de los mecanifóforos SP en el poliuretano a granel.
- Para cuantificar la apertura del anillo inducida por el estrés a la merocianina coloreada (MC) forma.
- Para estudiar la cinética de cierre y los efectos de la tensión mecánica en el equilibrio SP/MC.
Principales métodos:
- La polimerización de crecimiento por etapas para incorporar SP en poliuretano.
- Mediciones de absorción a tensión constante para cuantificar la conversión de SP a MC.
- Imágenes de fluorescencia para estudiar la cinética de cierre del mecanóforo.
Principales resultados:
- La apertura del anillo inducida por el estrés de SP a MC se cuantificó mediante cambios en la absorbancia.
- La cinética de cierre del mecanóforo se estudió utilizando imágenes de fluorescencia.
- Se informó de los efectos de la tensión mecánica en el equilibrio entre las formas de SP y MC.
Conclusiones:
- El poliuretano con mecanóforos SP demuestra la detección de estrés visual.
- El estudio proporciona datos cinéticos para la respuesta mecanoquímica en polímeros a granel.
- Los hallazgos apoyan el desarrollo de materiales inteligentes auto-sensores.
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