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Producción catalítica de copolímeros de bloque de olefinas a través de la polimerización de lanzamiento en cadena
Daniel J Arriola1, Edmund M Carnahan, Phillip D Hustad
1Dow Chemical Company, Building 1702, Midland, MI 48674, USA. djarriola@dow.com
Science (New York, N.Y.)
|May 6, 2006
Resumen
Este estudio introduce un nuevo sistema catalítico para los copolímeros de bloque de olefinas, creando materiales con segmentos duros y blandos alternados para una excelente elasticidad a altas temperaturas. Estos polímeros avanzados se producen de manera eficiente utilizando procesos continuos.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- La catálisis es la catálisis.
Sus antecedentes:
- Los copolímeros tradicionales de bloque de olefinas a menudo carecen de propiedades sintonizables para aplicaciones de alta temperatura.
- El desarrollo de materiales con puntos de fusión altos y bajas temperaturas de transición de vidrio es un desafío.
Objetivo del estudio:
- Desarrollar un sistema catalítico para la producción de copolímeros de bloque de olefinas con segmentos semicristalinos y amorfos distintos.
- Para lograr materiales con propiedades elastoméricas mejoradas a temperaturas elevadas.
Principales métodos:
- Utilizó un agente de transporte en cadena para transferir cadenas de polímero entre dos catalizadores distintos dentro de un solo reactor.
- Composición de copolímero controlada mediante el ajuste de la proporción de alfa-olefina al etileno en diferentes bloques.
Principales resultados:
- Se han producido con éxito copolímeros de bloque de olefinas con segmentos semicristalinos y amorfos alternados.
- Los copolímeros resultantes exhiben altas temperaturas de fusión y bajas temperaturas de transición de vidrio.
- Demostró excelentes propiedades elastoméricas a altas temperaturas.
Conclusiones:
- El sistema catalítico desarrollado permite la síntesis precisa de copolímeros avanzados de bloque de olefinas.
- Estos materiales ofrecen un rendimiento superior en aplicaciones a altas temperaturas.
- El proceso es adecuado para una producción continua económicamente favorable.
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