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Nueva transición de fase epitaxial entre DG y HEX en PS-b-PI
Hae-Woong Park1, Jueun Jung, Taihyun Chang
1Department of Chemistry and Polymer Research Institute, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Journal of the American Chemical Society
|December 17, 2008
Resumen
Los investigadores estudiaron las transiciones de fase en copolímeros de bloque utilizando imágenes avanzadas. Descubrieron una nueva vía para la transición de la doble tiroides a cilindros empacados hexagonalmente en películas delgadas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La ciencia de los polímeros es la ciencia de los polímeros.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los copolímeros de bloque se autoensamblan en nanoestructuras ordenadas.
- El control de la morfología de la película delgada es crucial para las aplicaciones de dispositivos.
Objetivo del estudio:
- Para investigar la transición de fase epitaxial de las fases de doble tiroides (DG) a las fases de cilindro empacado hexagonalmente (HEX).
- Para caracterizar la vía de transición en películas delgadas de poliestireno-b-poliisopreno copolímero de dibloque.
Principales métodos:
- Diseminación de rayos X de ángulo pequeño de incidencia de pastoreo (GISAXS).
- Microscopía de electrones de transmisión (TEM).
- Microtomografía de electrones de transmisión (TEMT) para imágenes 3D directas.
Principales resultados:
- Se logró la observación 3D directa de las fases DG y HEX coexistentes.
- Se identificó una nueva ruta de transición epitaxial de DG a HEX.
- Una buena orientación del dominio en películas delgadas facilitó las observaciones.
Conclusiones:
- TEMT proporciona una visualización 3D sin precedentes de las nanofasas coexistentes.
- La trayectoria de transición epitaxial identificada ofrece nuevos conocimientos sobre el autoensamblaje dirigido.
- Comprender estas transiciones es clave para la fabricación de materiales nanoestructurados avanzados.
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