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Stereoingeniería de poli (-1,3-metilenciclohexano) a través de la polimerización de coordinación de vida en dos
Kaitlyn E Crawford1, Lawrence R Sita
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Journal of the American Chemical Society
|May 23, 2013
Resumen
Los investigadores controlaron el intercambio dinámico de grupos metilo durante la polimerización de 1,6-heptadieno para crear poli (-1,3-metilenciclohexano) con variadas microestructuras, lo que influye en las propiedades a granel y el comportamiento del copolímero de bloque.
Área de la Ciencia:
- Química de Polímeros La química de los polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La polimerización de coordinación de vida ofrece un control preciso sobre la arquitectura del polímero.
- El intercambio dinámico de grupos metilo puede influir en las propiedades y la morfología del polímero.
Objetivo del estudio:
- Para controlar externamente el intercambio dinámico de grupos metilo en la polimerización de coordinación de la vida.
- Para generar poli ((1,3-metilenciclohexano) con microestructuras estereocímicas sistemáticamente variadas.
- Para investigar el impacto de la microestructura en las propiedades de la masa y el comportamiento de bloqueo del copolímero.
Principales métodos:
- La polimerización de coordinación en vivo de 1,6-heptadieno.
- Control externo del intercambio dinámico de grupos metilo entre especies activas y latentes.
- Variación sistemática de la microestructura estereoquímica.
- Caracterización de las propiedades a granel y el comportamiento de la microfase en estado sólido de polímeros y copolímeros de bloque.
Principales resultados:
- Se generó un espectro de formas físicas poli (1,3-metilenciclohexano) con microestructuras controladas.
- La estrategia manipuló con éxito las propiedades a granel del poli (1,3-metilenciclohexano).
- Se influyó en el comportamiento de la microfase en estado sólido de los copolímeros de bloque de poli{1,3-metilenciclohexano) -b-poli{1-hexeno).
Conclusiones:
- El control externo del intercambio dinámico de grupos metilo es una estrategia efectiva para ajustar la microestructura del polímero.
- Este control permite propiedades a granel personalizadas de poli (1,3-metilenciclohexano).
- El enfoque es aplicable a la modificación del comportamiento de los copolímeros de bloque.
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