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La polimerización de la cadena de crecimiento de 2-clorotiofenos promovida por los ácidos de Lewis
Baltasar Bonillo1, Timothy M Swager
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|November 10, 2012
Resumen
Los ácidos de Lewis permiten la polimerización del crecimiento de la cadena catiónica de los 2-cloroalquilenodioxitofenos, produciendo polímeros conjugados de alto peso molecular. Este proceso de polimerización en vivo permite la síntesis de nuevos copolímeros de bloque.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Síntesis orgánica La síntesis orgánica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los polímeros conjugados son cruciales para la electrónica orgánica.
- El control de la polimerización es clave para lograr las propiedades deseadas del polímero.
- Los 2-cloroalquilendioxitofenos son monómeros para polímeros funcionales.
Objetivo del estudio:
- Para investigar la polimerización catalizada por el ácido de Lewis de los 2-cloroalquilenodioxitofenos.
- Para aclarar el mecanismo de polimerización.
- Para sintetizar polímeros conjugados de alto peso molecular y copolímeros de bloque.
Principales métodos:
- La polimerización del crecimiento de la cadena catiónica utilizando ácidos de Lewis.
- Reacciones de tapa final para confirmar el mecanismo de polimerización.
- Monitoreo del peso molecular frente a la conversión de monómeros.
Principales resultados:
- Se sintetizaron con éxito polímeros conjugados de alto peso molecular.
- La polimerización se produce a través de un mecanismo de crecimiento de la cadena catiónica.
- Se demostró la naturaleza "viva" de la polimerización, lo que permite la síntesis de copolímeros en bloque.
Conclusiones:
- Los ácidos de Lewis catalizan efectivamente la polimerización catiónica viva de los 2-cloroalquilenodioxitiofenos.
- Este método proporciona una ruta a polímeros conjugados bien definidos y copolímeros de bloque.
- Los hallazgos abren caminos para nuevos materiales poliméricos funcionales.
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