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Copolimerización de eteno catalizado por paladio con acrolein dimethyl acetal: acción del catalizador y desactivación

Weidong Li¹, Xiaochun Zhang, Auke Meetsma

¹Dutch Polymer Institute/Center for Catalytic Olefin Polymerization, Stratingh Institute for Chemistry and Chemical Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

Journal of the American Chemical Society

|September 30, 2004

Resumen

La copolimerización de eteno con acrolein dimethyl acetal produce polímeros ramificados. La adición de metanol al sistema catalizador de paladio catiónico inhibe la desactivación, aumentando la productividad de este proceso de polimerización.

Área de la Ciencia:

Química de Polímeros La química de los polímeros es la química de los polímeros.
Química organometálica Química orgánica de los metales.

Sus antecedentes:

Los catalizadores catiónicos de alfa-diimina y paladio permiten la copolimerización del eteno.
El acrolein dimethyl acetal (ADMA) es un monómero funcional para crear arquitecturas de polímeros ramificados.

Objetivo del estudio:

Investigar la copolimerización del eteno con ADMA utilizando un catalizador de paladio.
Identificar y mitigar las vías de desactivación del catalizador para mejorar la eficiencia de la polimerización.

Principales métodos:

Copolimización de eteno y ADMA.
Utilizando un catalizador catiónico de quelato de alfa-diimina y paladio.
Monitoreo de los mecanismos de desactivación del catalizador.

Principales resultados:

Los copolímeros ramificados fueron sintetizados con éxito.
La desactivación del catalizador se identificó como la eliminación del metanol, formando una especie de paladio inerte.
La adición de metanol a la mezcla de reacción retrasó significativamente la desactivación.

Conclusiones:

La adición de metanol es una estrategia efectiva para mejorar la longevidad y la productividad del catalizador en la copolimización eteno-ADMA.
La comprensión de las vías de desactivación permite la optimización del proceso en la polimerización de olefinas catalizadas por paladio.

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