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Control sin precedentes sobre la polimerización del n-hexilisocianato utilizando un iniciador aniónico con función
Jun-Hwan Ahn1, Yeong-Deuk Shin, G Yogendra Nath
1Department of Materials Science and Engineering and Center for Frontier Materials (BK21), Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712, Korea.
Journal of the American Chemical Society
|March 24, 2005
Resumen
Los investigadores desarrollaron un nuevo iniciador, benzanilida de sodio (Na-BA), para la polimerización aniónica viva de los isocyanatos. Este método ofrece un excelente control sobre el peso molecular y la distribución del polímero, eliminando las reacciones secundarias y los aditivos externos.
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 aniónica viva de isocyanatos a menudo sufre reacciones secundarias.
- La iniciación rápida y el retroceso de la cadena conducen a un mal control sobre el peso molecular (MW) y la distribución del peso molecular (MWD).
Objetivo del estudio:
- Desarrollar un nuevo iniciador para la polimerización controlada de isocyanato.
- Para eliminar la necesidad de aditivos externos en la polimerización aniónica viva de isocyanatos.
Principales métodos:
- Utilizado benzanilida de sodio (Na-BA) como un nuevo iniciador.
- Investigó la cinética de polimerización y las características del polímero.
Principales resultados:
- Logró altos rendimientos y un control sin precedentes sobre MW y MWD.
- El Na-BA funciona como un iniciador y un aditivo, evitando la mordedura por la espalda.
- Se introdujeron varias funcionalidades en los terminales del polímero, produciendo macromonomeros y polímeros quirales en rendimientos de ~100%.
Conclusiones:
- El benzanilido de sodio permite la polimerización aniónica viva controlada de los isocyanatos.
- Este método expande las aplicaciones de los poliisocianatos a través de una versátil funcionalización.
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