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Copolimerización viva de etileno con estireno catalizado por el complejo de (ciclopentadienil) ---ketimida ---titanio
1Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0101, Japan.
Journal of the American Chemical Society
|June 30, 2005
Resumen
La copolimización viva de etileno y estireno se logró utilizando un catalizador específico de titanio y un cocatalizador de metilaluminoxano (MAO). Este nuevo método permite la síntesis controlada de polímeros, a diferencia de las técnicas tradicionales de homopolimerización.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química organometálica Química orgánica de los metales.
Sus antecedentes:
- Las técnicas de polimerización viva son cruciales para la síntesis de polímeros con arquitecturas controladas.
- La copolimerización de etileno y estireno presenta desafíos para lograr el crecimiento controlado de la cadena.
Objetivo del estudio:
- Para investigar la copolimerización en vivo de etileno y estireno utilizando un catalizador específico de titanio.
- Comprender la influencia de la estructura del catalizador en el comportamiento de la copolimización y la incorporación de estireno.
Principales métodos:
- Copolimerización de etileno y estireno utilizando el catalizador Cp*TiCl2(N=CtBu2) y el cocatalizador de metilaluminoxano (MAO).
- Análisis del polietileno-co-estireno resultante para determinar la estructura del polímero y la incorporación de estireno.
Principales resultados:
- El sistema específico de catalizador de titanio demostró la copolimización viva de etileno y estireno.
- Ni la homopolimerización de etileno ni de estireno se llevó a cabo de manera viva con este catalizador.
- No se observaron unidades de repetición de estireno en los copolímeros resultantes, lo que indica la inhibición de la transferencia de la cadena.
Conclusiones:
- El sistema de catalizador Cp*TiCl2(N=CtBu2) con MAO permite la copolimerización de etileno estireno vivo.
- El comportamiento único sugiere que la inserción de estireno, incluso si no se incorpora a la cadena principal, puede influir en los mecanismos de transferencia de la cadena.
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