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Un equivalente activado de lactida hacia la polimerización de apertura de anillo organocatalítico
Olivier Thillaye du Boullay1, Emmanuel Marchal, Blanca Martin-Vaca
1Laboratoire Hétérochimie Fondamentale et Appliquée du CNRS (UMR 5069), Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 09, France.
Journal of the American Chemical Society
|December 21, 2006
Resumen
El equivalente alfa-lactona, lacOCA, muestra una mayor reactividad que el lactido en la polimerización de apertura de anillo (ROP). Este método produce ácidos polilácticos con propiedades controladas bajo condiciones suaves.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La polimerización por apertura de anillos (ROP) es un método clave para la síntesis de poliéster.
- Lactida es un monómero común para ROP, pero su reactividad puede ser limitada.
- El desarrollo de monómeros más reactivos puede mejorar la eficiencia y el control de la polimerización.
Objetivo del estudio:
- Para investigar la reactividad de lacOCA, un equivalente de alfa-lactona, en ROP catalizado por nucleófilo.
- Para comparar el rendimiento de lacOCA con lactida en reacciones ROP.
- Para lograr una síntesis controlada de ácidos polilácticos (PLA) con pesos moleculares específicos y baja polidispersidad.
Principales métodos:
- La polimerización de apertura de anillo catalizada por nucleófilo (ROP).
- Se utilizó 4-dimetilaminopiridina (DMAP) como catalizador.
- Empleó varios iniciadores protóticos para la polimerización.
- Caracterizó los polímeros resultantes para el peso molecular y la polidispersidad.
Principales resultados:
- lacOCA demostró una reactividad significativamente mayor en comparación con el lactido en la ROP catalizada por nucleófilo.
- Se lograron pesos moleculares controlados y polidispersidades estrechas de PLA.
- Las polimerizaciones procedieron efectivamente bajo condiciones de reacción suaves.
Conclusiones:
- lacOCA es un monómero altamente reactivo para ROP, superando el rendimiento de la lactida.
- El uso de DMAP e iniciadores protóticos permite una síntesis eficiente y controlada de PLA de lacOCA.
- Este enfoque ofrece una valiosa alternativa para la producción de ácidos polilácticos de alta calidad.
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