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Síntesis de materiales poliolefinos semicristalinos: ramificación de metilo de precisión a través de la caminata en

David N Vaccarello¹, Kyle S O'Connor¹, Pasquale Iacono¹

¹Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States.

Journal of the American Chemical Society

|April 24, 2018

Resumen

Los nuevos catalizadores de níquel simétricos con C2 permiten la polimerización regioselectiva e isoselectiva del 1-buteno. Esto produce una nueva poliolefina semicristalina con una alta preservación de la estereoquímica a través de la caminata en cadena.

Área de la Ciencia:

Química de los polímeros
Catálisis organometálica
Ciencias de los materiales

Sus antecedentes:

Las poliolefinas son materiales industriales cruciales.
La polimerización estereocontrolada de las olefinas sigue siendo un desafío.
La polimerización en cadena ofrece arquitecturas poliméricas únicas.

Objetivo del estudio:

Desarrollar nuevos catalizadores para la polimerización estereoselectiva del 1-buteno.
Para investigar la producción de isotáctico 4,2-poly ((1-buteno).
Para explorar los mecanismos de caminar en cadena en la polimerización de las olefinas.

Principales métodos:

Síntesis de catalizadores de níquel simétricos con C2.
Polimerización regionalizada e isoselectiva del 1-buteno.
Caracterización de la microestructura y las propiedades térmicas del polímero.

Principales resultados:

Descubrimiento de catalizadores de níquel simétricos con C2 para la polimerización del 1-buteno.
Producción de 4,2-poli-buteno isotáctico, una nueva poliolefina semicristalina.
Se obtienen elevadas selectividades enantiofaciales (hasta el 84%) y temperaturas de fusión (hasta los 86 °C).

Conclusiones:

Este sistema catalítico permite un control estereoquímico preciso en la polimerización en cadena.
Se sintetizó una nueva poliolefina semicristalina con aplicaciones potenciales.
Representa un avance significativo en la polimerización estereoselectiva de las olefinas.

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