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Metátesis selectiva de dieno acíclico polimerización de α,ω-dienos

Samuel J Kempel¹, Ting-Wei Hsu¹, Jake L Nicholson¹

¹Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.

Journal of the American Chemical Society

|May 31, 2023

Resumen

Los investigadores desarrollaron un nuevo método para la polimerización de la metatesis acíclica cis (ADMET). Esta técnica controla con precisión la estereoquímica del polímero, permitiendo propiedades térmicas y mecánicas a medida en materiales blandos.

Área de la Ciencia:

Química de los polímeros
Ciencias de los materiales
Síntesis orgánica

Sus antecedentes:

La estereoquímica de las unidades de repetición de polímeros influye significativamente en las propiedades del material.
Los métodos sintéticos existentes carecen de un control preciso del isomerismo cis/trans en los polímeros.
La metatesis de dieno acíclico (ADMET) es una técnica de polimerización con potencial para el control estereoquímico.

Objetivo del estudio:

Desarrollar un método de polimerización ADMET cis selectivo.
Para sintetizar polímeros con alto contenido de cis y tolerancia al grupo funcional.
Investigar el impacto de la geometría cis en las propiedades del polímero.

Principales métodos:

Se utilizó un catalizador de rutenio (Ru) ciclometalizado altamente estereoselectivo para la polimerización de ADMET.
Se han polimerizado varios monómeros alfa y omega-dieno.
Copolímeros de ABA tribloqueados sintetizados que incorporan segmentos de poliocténameros ricos en cis.

Principales resultados:

Se ha logrado una polimerización cis-selectiva de ADMET con un contenido de cis de hasta el 99%.
Se ha demostrado una alta tolerancia del grupo funcional al método desarrollado.
Se demostró la influencia de la geometría cis en las propiedades térmicas y mecánicas de los polialquenámeros.

Conclusiones:

La polimerización ADMET cis-selectiva es una estrategia eficiente para ajustar las propiedades del polímero.
El control preciso de la estereoquímica permite el diseño de materiales blandos avanzados.
El sistema catalítico desarrollado ofrece una amplia aplicabilidad para la síntesis de polímeros.

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