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Comportamiento de copolimización del monómero etileno/polar de los complejos bis ((fenóxi-imeno) Ti: formación de
Hiroshi Terao1, Seiichi Ishii, Makoto Mitani
1Research Center, Mitsui Chemicals, Inc., 580-32 Nagaura, Sodegaura, Chiba, 299-0265, Japan.
Journal of the American Chemical Society
|December 11, 2008
Resumen
Los catalizadores de titanio con ligandos bis ((phenoxy-imine) específicos facilitan la copolimización del etileno y el 5-hexeno-1-il-acetato. Estos complejos de metales de transición del grupo 4 son prometedores en la polimerización de las olefinas.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
Sus antecedentes:
- Los complejos de metales de transición del grupo 4 son cruciales en la polimerización de las olefinas.
- Los ligandos bis ((phenoxy-imine) ofrecen propiedades estéricas y electrónicas sintonizables para el diseño de catalizadores.
- La copolimerización del etileno con olefinas funcionalizadas presenta desafíos en el control de la microestructura del polímero.
Objetivo del estudio:
- Investigar la actividad catalítica de los nuevos complejos de titanio bis ((fenoxi-imeno).
- Para explorar la copolimización del etileno y el 5-hexeno-1-il-acetato utilizando estos catalizadores de titanio.
- Para entender la influencia de la estructura del ligando en el rendimiento catalítico.
Principales métodos:
- Síntesis y caracterización de los complejos de titanio bis ((fenoxi-amina).
- Reacciones de copolimerización de etileno y 5-hexeno-1-il-acetato bajo diversas condiciones.
- Análisis de los copolímeros resultantes utilizando técnicas como la espectroscopia de RMN y GPC.
Principales resultados:
- Los complejos de titanio mediaron efectivamente la copolimización del etileno y el 5-hexeno-1-il-acetato.
- La presencia de un grupo ortofenilo en la fracción fenoxi influyó en la actividad catalítica.
- Se logró la incorporación de 5-hexeno-1-il-acetato en la cadena de polietileno.
Conclusiones:
- Los complejos de titanio bis ((fenoxi-imina) son catalizadores activos para la copolimización de etileno/olefina funcionalizada.
- El diseño de los ligandos, específicamente la sustitución de ortofenilo, juega un papel en el rendimiento del catalizador.
- Estos hallazgos abren caminos para la creación de nuevas poliolefinas funcionales.
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