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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
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Catalizadores heterogéneos de un solo sitio para la polimerización de olefinas mediante intercambio catiónico en un
Robert J Comito1, Keith J Fritzsching2, Benjamin J Sundell3
1Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|July 23, 2016
Resumen
Las estructuras metal-orgánicas (MOF) permiten la producción avanzada de poliolefinas. Al intercambiar iones de zinc en MFU-4l con otros metales, los investigadores crearon un catalizador sólido versátil para la síntesis precisa de polímeros y el control de la morfología.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Química de los polímeros
Sus antecedentes:
- Las poliolefinas avanzadas se basan en catalizadores heterogéneos de un solo sitio.
- Las estructuras metálico-orgánicas (MOF) ofrecen un diseño molecular sintonizable para la catálisis.
- El MFU-4l es un MOF de gran superficie con potencial para aplicaciones industriales.
Objetivo del estudio:
- Desarrollar una plataforma general para la polimerización selectiva de olefinas utilizando catalizadores basados en MOF.
- Investigar la actividad catalítica del MFU-4l intercambiado con metales para la polimerización de olefinas.
- Para demostrar el control molecular y morfológico en la síntesis de polietileno.
Principales métodos:
- Un marco orgánico-metálico sintetizado MFU-4l.
- Intercambio de iones de zinc en el MFU-4l con metales reactivos.
- Caracterizó el polietileno resultante utilizando varias técnicas analíticas.
- Evaluación del rendimiento del catalizador en la copolimerización de etileno y propileno.
Principales resultados:
- Los catalizadores MFU-41 intercambiados por metales muestran una reactividad similar a la de un solo sitio con índices de polidispersión bajos.
- Logró un buen control sobre el peso molecular y la morfología del polímero.
- Se ha demostrado la exitosa copolimerización de etileno y propileno.
- El crecimiento uniforme del polímero alrededor de las partículas del catalizador ofrece control morfológico.
Conclusiones:
- Los MOF intercambiados por metales proporcionan una plataforma versátil para la polimerización selectiva de las olefinas.
- Estos catalizadores ofrecen un control molecular y morfológico, crucial para la catálisis industrial.
- Los catalizadores MOF desarrollados son prometedores para los procesos de flujo continuo en la fabricación de poliolefinas.
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