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Policondensación de transferencia de catalizador controlado y polimerización iniciada en la superficie de un monómero
Songsu Kang1, Robert J Ono, Christopher W Bielawski
1Department of Chemistry and Biochemistry, The University of Texas at Austin , Austin, Texas 78712, United States.
Journal of the American Chemical Society
|March 26, 2013
Resumen
Un nuevo método de transferencia de catalizador de policondensación proporciona bien definido poli (p-fenilenetileno) (PPE) con pesos moleculares controlados. Esta polimerización de crecimiento en cadena permite la síntesis de copolímeros de bloque de EPI y cepillos de EPI injertados en superficie.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Síntesis orgánica La síntesis orgánica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El poli (p-fenilenetileno) (PPE) son polímeros conjugados prominentes con propiedades optoelectrónicas significativas.
- La síntesis controlada de arquitecturas bien definidas de EPI sigue siendo un desafío en la química de polímeros.
Objetivo del estudio:
- Desarrollar un nuevo método de transferencia de catalizadores por policondensación para la síntesis de EPI bien definidos.
- Para demostrar el control sobre el peso molecular y la arquitectura del polímero.
- Explorar la aplicación de este método en la creación de copolímeros de bloque y polímeros injertados en superficie.
Principales métodos:
- Catalizador de transferencia de policondensación utilizando un derivado estanilado de 4-iodofenilacetileno y un catalizador de paladio (PhPd(t-Bu3P) Br).
- Optimización de las condiciones de reacción para controlar el peso molecular y las propiedades del polímero.
- Técnicas de polimerización de crecimiento en cadena para sintetizar copolímeros de bloque y cepillos de polímero iniciados en la superficie.
Principales resultados:
- Se logró hasta un 94% de rendimiento de EPI bien definidos.
- Aumento lineal demostrado en el peso molecular del polímero con el consumo de monómeros.
- Se han producido con éxito copolímeros de bloque que contienen EPI y cepillos de EPI a partir de nanopartículas de sílice.
Conclusiones:
- La policondensación por transferencia de catalizadores es un método eficaz para sintetizar EPI bien definidos.
- La naturaleza de la cadena de crecimiento permite un control preciso de la arquitectura del polímero, incluidos los copolímeros de bloque y los materiales injertados en superficie.
- Esta metodología abre nuevas vías para la creación de materiales poliméricos conjugados avanzados para diversas aplicaciones.
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