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Colapso de polímeros rígidos conjugados con defectos químicos en conformaciones cilíndricas ordenadas

¹Department of Chemistry & Biochemistry, University of Texas, Austin 78712, USA.

|July 13, 2000

Resumen

Los polímeros conjugados rígidos, como el poli[2-metoxi-5-(2'-etilhexilo) oxy-1,4-fenilenovinileno], adoptan conformaciones cilíndricas ordenadas debido a defectos químicos. Estas estructuras son clave para sus excepcionales propiedades fotofísicas.

Área de la Ciencia:

La ciencia de los polímeros es la ciencia de los polímeros.
Ciencia de los materiales Ciencia de los materiales.
La espectroscopia es una técnica de espectroscopia.

Sus antecedentes:

Las propiedades del polímero dependen de la conformación de la cadena.
Los polímeros flexibles forman bobinas desordenadas o glóbulos fundidos.
Se predice que los polímeros rígidos formarán toroides o varillas ordenadas.

Objetivo del estudio:

Investigar la conformación del poli[2-metoxi-5-(2'-etilhexilo) oxí-1,4-fenileno vinileno].
Correlación de la conformación con las propiedades fotofísicas observadas.
Comprender el papel de los defectos químicos en la estructura del polímero.

Principales métodos:

Simulaciones por ordenador. simulaciones por ordenador.
Mediciones de espectroscopia de polarización en moléculas de polímeros individuales.

Principales resultados:

La conformación del polímero está altamente ordenada y colapsada, no son toroides o varillas ideales.
Los defectos químicos tetraédricos crean segmentos casi rectos.
Estos segmentos permiten conformaciones cilíndricas.

Conclusiones:

Las conformaciones cilíndricas son críticas para las propiedades fotofísicas de los polímeros conjugados.
La transferencia de energía intramolecular eficiente y la anisotropía óptica están vinculadas a estas estructuras.

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