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Excimeros de polímeros conjugados de alta emisión con excimeros de polímeros conjugados de alta emisión
Youngmi Kim1, Jean Bouffard, Steven E Kooi
1Department of Chemistry and Institute for Soldier Nanotechnologies, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|September 30, 2005
Resumen
Los nuevos poli (fenileno etileno) con estructuras de anillo únicas superan el apagado causado por la agregación, produciendo materiales de estado sólido de alta emisión para dispositivos avanzados.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- La fotofísica es la fotofísica.
Sus antecedentes:
- Los polímeros conjugados a menudo sufren una eficiencia de fluorescencia reducida en los estados agregados debido a las interacciones interpolímeros que forman especies de emisión débil.
- Estas pérdidas de emisión inducidas por la agregación limitan su aplicación en dispositivos optoelectrónicos.
Objetivo del estudio:
- Para investigar nuevos poli (fenileno etileno) s con estructuras de anillo de colgante fundido [2.2.2].
- Comprender el origen de la emisión de estado sólido con desplazamiento al rojo de alta emisión en estos nuevos materiales.
Principales métodos:
- Síntesis de poli (fenileno etinile) s con estructuras de anillo específicas [2.2.2] y puentes de alquenos sustituidos por ésteres.
- Estudios fotofísicos en soluciones, películas delgadas con recubrimiento espinoso, soluciones sólidas y películas de Langmuir.
Principales resultados:
- Los polímeros diseñados exhiben espectros de emisión altamente emisores, amplios y con desplazamiento al rojo en estado sólido.
- Las nuevas especies emisoras se identifican como excimeros formados a través de interacciones entre cadenas mediadas por el sistema de anillos [2.2.2].
Conclusiones:
- El sistema de anillos fusionados [2.2.2] media efectivamente las interacciones entre cadenas para producir excimeros de polímero conjugado de alta emisión.
- Esta estrategia de diseño ofrece una vía para adaptar las propiedades de emisión en polímeros conjugados para aplicaciones de electroluminiscencia y sensoriales.
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