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Funcionalización de radicales de oxígeno de las nanohojas de nitruro de boro
Toby Sainsbury1, Amro Satti, Peter May
1Centre for Research on Adaptive Nanostructures and Nanodevices, Trinity College Dublin, Ireland. toby.sainsbury@gmail.com
Journal of the American Chemical Society
|October 30, 2012
Resumen
Se sintetizaron nanohojas hexagonales de nitruro de boro covalentemente funcionalizadas (BNNS) con grupos hidroxilo. Estos BNNS modificados mejoraron las propiedades mecánicas de los nanocompuestos de polímero a través de una mejor unión interfacial.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química de las superficies.
Sus antecedentes:
- Las nanohojas hexagonales de nitruro de boro (BNNS) poseen propiedades únicas, pero requieren una modificación de la superficie para aplicaciones avanzadas.
- La funcionalización covalente es una estrategia clave para adaptar las propiedades de BNNS y mejorar su integración en materiales compuestos.
Objetivo del estudio:
- Desarrollar un nuevo método de funcionalización química covalente para BNNSs.
- Para sintetizar BNNSs funcionalizados con hidroxilo (OH-BNNSs) a través de un enfoque de radicales de oxígeno en dos pasos.
- Para investigar el impacto de OH-BNNSs en las propiedades mecánicas de los nanocompuestos de polímero.
Principales métodos:
- Funcionalización de los radicales de oxígeno en la fase de solución de los átomos de boro en la red h-BN.
- Injerto en dos pasos de grupos alkoxi seguido de desfuncionalización hidrolítica para obtener OH-BNNSs.
- Caracterización mediante el uso de HR-TEM, Raman, UV-vis, FTIR, NMR y TGA.
Principales resultados:
- Injerto covalente exitoso de grupos alkoxi y posterior formación de grupos hidroxilo en BNNSs.
- Demostración de propiedades mecánicas mejoradas en nanocompuestos poliméricos preparados con OH-BNNSs.
- Análisis de la influencia de la unión interfacial covalente y no covalente en el rendimiento de los compuestos.
Conclusiones:
- Se estableció un método robusto para la funcionalización covalente de BNNSs, dando lugar a OH-BNNSs.
- Los BNNS funcionalizados con hidroxilo mejoran significativamente las propiedades mecánicas de los nanocompuestos poliméricos.
- El estudio pone de relieve el papel crítico de la unión interfacial en la determinación del rendimiento del compuesto nanocargador-polímero.
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