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La transesterificación catalizada por metales para la cicatrización y el ensamblaje de thermosets
Mathieu Capelot1, Damien Montarnal, François Tournilhac
1Matière Molle et Chimie (UMR 7167 ESPCI-CNRS), Ecole Supérieure de Physique et Chimie Industrielles de la Ville de Paris ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France.
Journal of the American Chemical Society
|April 28, 2012
Resumen
El control catalítico de las reacciones de intercambio de enlaces permite la reparación de polímeros reticulados. Esto permite la soldadura adaptable y el ensamblaje de termofijos epoxi, ofreciendo ventajas sobre los termoplásticos.
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.
Sus antecedentes:
- Las redes de polímeros reticulados, como los termocetos epoxi, son conocidos por su durabilidad, pero por lo general carecen de capacidades de autocuración.
- Los termofijos tradicionales son difíciles de reparar o reprocesar una vez curados, lo que limita su aplicación y vida útil.
Objetivo del estudio:
- Para investigar el control catalítico de las reacciones de intercambio de enlaces para la autocuración en materiales termoestables epoxi.
- Para demostrar la cinética de curación dependiente de la temperatura y explorar el impacto de la concentración del catalizador.
Principales métodos:
- Utilizó catalizadores de transesterificación para promover reacciones de intercambio de enlaces en redes termoestables de ácido epoxi y anhídrido epoxi.
- Estudió las capacidades curativas tanto a altas como a bajas temperaturas.
- Empleó moléculas modelo para analizar la cinética del proceso de curación.
Principales resultados:
- Se logró una curación efectiva de los termocetos epoxi reticulados a altas temperaturas a través de la transesterificación.
- Se observaron reacciones de intercambio lento y propiedades clásicas de termofijación a temperaturas más bajas.
- Se confirmó que la cinética de curación está directamente correlacionada con la velocidad de reacción de transesterificación.
- Demostró que la concentración de catalizadores ofrece control sobre los procesos de soldadura y ensamblaje.
Conclusiones:
- El control catalítico de las reacciones de intercambio de enlaces proporciona un mecanismo viable para la curación de los termocetos epoxi.
- La cinética dependiente de la temperatura permite la curación y el procesamiento sintonizables.
- Este enfoque ofrece un mayor control y flexibilidad en el ensamblaje de termocetos epoxi en comparación con los termoplásticos.
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