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Copolímeros tribloqueantes poli (styrene-b-diene-b-styrene) de alto rendimiento de un iniciador dicarbaniónico
Rachid Matmour1, Arvind S More, Prakash P Wadgaonkar
1Laboratoire de Chimie des Polymères Organiques, ENSCPB, Université Bordeaux 1, 16 Avenue Pey Berland, 33607 Pessac Cedex, France.
Journal of the American Chemical Society
|June 22, 2006
Resumen
Los investigadores desarrollaron un nuevo iniciador de organolitio sin aditivos para la síntesis de estireno-butadieno-estireno (SBS) copolímeros de bloque. Este avance produce SBS de alta calidad con propiedades mecánicas superiores, avanzando la producción de elastómeros 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.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Los copolímeros de bloque de estireno-butadieno-estireno (SBS) son extensamente utilizados como elastómeros termoplásticos.
- Los métodos de síntesis tradicionales pueden implicar procedimientos complejos o aditivos.
- Es deseable lograr una alta microestructura de 1,4-polibutadieno y excelentes propiedades mecánicas.
Objetivo del estudio:
- Diseñar y sintetizar un nuevo iniciador de organolitio dicarbaniónico soluble en hidrocarburos y sin aditivos.
- Para utilizar este iniciador para la polimerización aniónica de butadieno y estireno.
- Para producir copolímeros triblock bien definidos de poli (estireno-b-butadieno-b-estireno) (SBS) con propiedades mejoradas.
Principales métodos:
- Se sintetizó un nuevo iniciador de organolitio dicarbaniónico a través de una reacción de intercambio halógeno-litio (reacción de Gilman) a partir de un diarilhalido con una cadena de alquilo C15.
- El iniciador se utilizó para iniciar la polimerización aniónica del butadieno y el estireno.
- Caracterización de los copolímeros triblock resultantes, incluido el análisis de la microestructura y las pruebas mecánicas.
Principales resultados:
- El nuevo iniciador produjo con éxito bien definidos copolímeros tribloqueantes de poliestireno-b-butadieno-b-estireno (SBS).
- Los segmentos de polibutadieno exhibieron un alto porcentaje de 1,4-microstructura (91%).
- Los polímeros SBS sintetizados demostraron excelentes propiedades mecánicas, incluida la resistencia a la tracción final >30 MPa y el alargamiento al romperse del 1000%.
Conclusiones:
- El iniciador de organolitio sin aditivos desarrollado ofrece una ruta simplificada y efectiva para sintetizar copolímeros de bloque SBS de alto rendimiento.
- Este método representa un avance significativo en la producción de elastómeros termoplásticos.
- Los polímeros SBS resultantes poseen características microstruturales y mecánicas superiores adecuadas para aplicaciones avanzadas.
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