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Functionalization of Single-walled Carbon Nanotubes with Thermo-reversible Block Copolymers and Characterization by Small-angle Neutron Scattering
Published on: June 1, 2016
Análisis del grado de funcionalización de los nanotubos de carbono de pared única que tienen varios sustituyentes
Yutaka Maeda1, Kazuma Saito, Norihisa Akamatsu
1Department of Chemistry, Tokyo Gakugei University, Tokyo 184-8501, Japan.
Journal of the American Chemical Society
|October 13, 2012
Resumen
La funcionalización de los nanotubos de carbono de pared única (SWNT) mejora la solubilidad. El control de la adición de sustituyentes es clave para preservar las propiedades electrónicas, ya que el volumen de los grupos alquilo permite un control preciso de la funcionalidad.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química orgánica es la química orgánica.
Sus antecedentes:
- La funcionalización de nanotubos de carbono de pared única (SWNT) mejora la solubilidad y modifica las propiedades.
- El exceso de funcionalidad puede degradar las propiedades electrónicas intrínsecas de los SWNT.
- El control preciso sobre el grado y el tipo de funcionalidad es crucial para aplicaciones a medida.
Objetivo del estudio:
- Para sintetizar y caracterizar SWNTs funcionalizados en la pared lateral con grados controlados de sustitución.
- Investigar el impacto de la voluminosidad del sustituto en el proceso de funcionalización.
- Para explorar los efectos de sustitución en la alquilación reductora y la sililación de SWNTs.
Principales métodos:
- Síntesis de un solo bote de SWNT funcionalizados utilizando alquillitio y bromuro de alquilo.
- Caracterización a través de la espectroscopia de absorción, la espectroscopia Raman y el análisis termogravimétrico (TGA).
- Análisis de las relaciones de sustituyentes utilizando datos combinados espectroscópicos y TGA.
Principales resultados:
- Desarrolló un método para controlar el grado de funcionalización en las paredes laterales de SWNT.
- Demostró que el volumen de los grupos alquilo en el alquilitio y el bromuro de alquilo influye en la funcionalidad.
- Cuantificó la proporción de diferentes sustituyentes en SWNTs funcionalizados.
- Efectos de sustitución investigados en la alquilación y la sililación reductoras.
Conclusiones:
- El grado de funcionalización en SWNT puede ser controlado eficazmente mediante la manipulación de la masa estérica de los sustituyentes de alquilo.
- Este control permite ajustar las propiedades de SWNT mientras se minimiza la degradación de las características electrónicas.
- El estudio proporciona información sobre la síntesis y caracterización de SWNTs funcionalizados con precisión para aplicaciones avanzadas.
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