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La polimerización radical que vive en tándem simultánea: copolímeros de gradiente a través de la transformación in
Kazuhiro Nakatani1, Takaya Terashima, Mitsuo Sawamoto
1Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Journal of the American Chemical Society
|September 4, 2009
Resumen
Los investigadores desarrollaron un método novedoso de una sola olla para crear copolímeros de gradiente utilizando polimerización radical simultánea en tándem. Esta técnica transforma eficientemente los monómeros in situ, ofreciendo una forma conveniente de producir materiales poliméricos avanzados.
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.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Los copolímeros de gradiente ofrecen propiedades únicas en comparación con los copolímeros aleatorios o en bloque.
- Los métodos existentes para sintetizar copolímeros de gradiente pueden ser complejos e ineficientes.
- La transformación de monómeros in situ presenta una ruta potencial para simplificar la síntesis de copolímeros de gradiente.
Objetivo del estudio:
- Desarrollar una metodología novedosa, eficiente y conveniente para la producción de copolímeros de gradiente.
- Para utilizar simultáneamente la polimerización de radicales vivos en tándem con transformación de monómero in situ.
- Para explorar la síntesis de diversos copolímeros de gradiente con diferentes grupos laterales.
Principales métodos:
- La polimerización radical simultánea de la vida en tándem con el uso de catálisis de rutenio.
- El uso de alcóxidos metálicos (por ejemplo, Al ((Oi-Pr) 3) y disolventes alcohólicos (ROH) para la transesterificación in situ.
- Transformación gradual de los monómeros de metil (met) acrilato (M) en alquil (met) acrilatos (R) durante la polimerización.
Principales resultados:
- Se han producido con éxito copolímeros de gradiente bien controlados con diferentes composiciones de monómeros a lo largo de la cadena de polímeros.
- Se ha demostrado la conversión del metacrilato de metilo (MMA) en metacrilato de etilo (EMA) utilizando etanol y Al ((Oi-Pr) 3.
- Sintetizó varios copolímeros de gradiente con largas cadenas de alquilo y grupos pendentes de PEG utilizando diferentes alcoholes.
Conclusiones:
- La polimerización radical simultánea en tándem es un método eficaz para sintetizar copolímeros de gradiente.
- Este enfoque ofrece una estrategia conveniente y eficiente de una sola olla para la síntesis de polímeros.
- Los copolímeros de gradiente resultantes exhiben propiedades físicas distintas en comparación con sus contrapartes aleatorias y de bloque.
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