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Ensamblaje no covalente. Una estrategia racional para la realización de la polimerización supramolecular de
Jiheong Kang1, Daigo Miyajima2, Tadashi Mori3
1RIKEN Center for Emergent Matter Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Science (New York, N.Y.)
|February 7, 2015
Resumen
Los investigadores desarrollaron un nuevo método de polimerización de crecimiento de cadena para polímeros supramoleculares. Este mecanismo de polimerización vivo permite un control preciso de la estructura del polímero y permite la resolución óptica de los monómeros.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química supramolecular de las moléculas.
Sus antecedentes:
- La polimerización supramolecular ha avanzado en el diseño de materiales blandos funcionales.
- Los métodos existentes a menudo se basan en mecanismos de crecimiento gradual, lo que limita el control de las propiedades del polímero.
Objetivo del estudio:
- Desarrollar un mecanismo de polimerización de crecimiento en cadena para polímeros supramoleculares.
- Para lograr un control preciso sobre la longitud de la cadena de polímero, la secuencia y la estereoquímica.
- Para permitir la resolución óptica de los monómeros racémicos.
Principales métodos:
- Diseño de monómeros metastables con enlaces de hidrógeno intramoleculares promovidos por la forma.
- Utilizando iniciadores personalizados para desencadenar la polimerización.
- Caracterizar el proceso de polimerización como un mecanismo vivo.
Principales resultados:
- Se ha demostrado la polimerización de la cadena de crecimiento para polímeros supramoleculares.
- Lograr características de polimerización viva, incluido el control sobre el crecimiento de la cadena.
- Mostró la polimerización estereoselectiva, lo que lleva a la resolución óptica de un monómero racémico.
Conclusiones:
- La polimerización de crecimiento por cadena desarrollada supera las limitaciones de los mecanismos de crecimiento por etapas.
- Este nuevo enfoque ofrece un control sin precedentes sobre la arquitectura de polímeros supramoleculares.
- Permite la síntesis de materiales supramoleculares ópticamente puros.
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