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Funcionalización controlada de nanotubos de carbono de paredes múltiples mediante la polimerización radical de
Hao Kong1, Chao Gao, Deyue Yan
1College of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China.
Journal of the American Chemical Society
|January 15, 2004
Resumen
Los investigadores injertaron poli ((metacrilato de metilo) en nanotubos de carbono de paredes múltiples mediante la polimerización radical por transferencia atómica. Este método crea nuevos nanomateriales híbridos con espesor y estructura de pincel de polímero ajustable.
Área de la Ciencia:
- Química de Polímeros La química de los polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los monómeros como el metacrilato de metilo (MMA) se pueden injertar en superficies para modificar las propiedades del material.
- La polimerización radical por transferencia atómica (ATRP) es una técnica de polimerización controlada adecuada para crear cepillos de polímero.
- Los nanotubos de carbono de paredes múltiples (MWNT) poseen propiedades únicas, pero requieren funcionalización de la superficie para muchas aplicaciones.
Objetivo del estudio:
- Para injertar poli (methacrilato de metilo) (PMMA) en nanotubos de carbono de paredes múltiples (MWNT) utilizando un ATRP in situ "injertado desde" enfoque.
- Para controlar el grosor de las capas de polímero injertado mediante el ajuste de la relación monómero-iniciador.
- Extender el método para crear copolímeros de bloque y nuevos nanoobjetos híbridos de núcleo y cáscara.
Principales métodos:
- Técnica de "injerto desde" ATRP in situ.
- Funcionalización de la superficie de las MWNT con bromo (MWNT-Br).
- Caracterización mediante el uso de FTIR, 1H NMR, SEM, TEM y TGA.
- Copolimización para crear copolímeros de bloque (PMMA-b-PHEMA).
Principales resultados:
- Injerto exitoso de PMMA en las superficies de MWNT, formando cepillos de polímero.
- Control demostrado sobre el grosor de la capa de polímero a través de la proporción de alimentación.
- Confirmó la estructura y las propiedades de los materiales híbridos resultantes.
- Sintetizó nuevos nanoobjetos con núcleo MWNT/PMMA-b-PHEMA-shell.
Conclusiones:
- El enfoque ATRP in situ de "injerto de" es efectivo para crear cepillos de polímero en MWNTs.
- Este método permite un control preciso sobre el grosor de la capa de polímero y la creación de arquitecturas complejas.
- La técnica desarrollada ofrece una vía para diseñar nanomateriales y dispositivos moleculares avanzados basados en MWNT.
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