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Transición reversible de la fase sólida a la fase líquida de los cristales de polímeros de coordinación
Daiki Umeyama1, Satoshi Horike, Munehiro Inukai
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University , Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Journal of the American Chemical Society
|December 23, 2014
Resumen
Los investigadores informan de la primera transición reversible de la fase sólida a la fase líquida en polímeros de coordinación cristalina (PC). Este descubrimiento abre nuevas vías para materiales funcionales y técnicas de fabricación avanzadas utilizando CPs de fusión.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
- Química del estado sólido.
Sus antecedentes:
- Las transiciones de fase de sólido a líquido son fundamentales pero poco estudiadas en los polímeros de coordinación (PC).
- Los CPs ofrecen una rica funcionalidad con aplicaciones potenciales.
- Investigar las transiciones de fase en PC puede desbloquear nuevas propiedades de materiales y métodos de procesamiento.
Objetivo del estudio:
- Informar e investigar la transición reversible de la fase sólida a la fase líquida en los polímeros de coordinación cristalina.
- Explorar los cambios estructurales de estos CPs "fundidos" en estados líquido y vidrio.
- Para demostrar la fabricación de formas de materiales avanzados utilizando esta transición de fase.
Principales métodos:
- Síntesis de polímeros de coordinación a base de zinc que incorporan fosfato y azoles.
- Análisis estructural de los estados cristalino, líquido y vidrio utilizando técnicas como la difracción de rayos X (no explícita pero implícita).
- Fabricación de películas delgadas y cristales de monolito a través del proceso de transición de fase.
Principales resultados:
- Se ha demostrado la transición reversible de la fase sólida a la fase líquida en PC cristalinas.
- Se observó que los enlaces de coordinación se interrumpen parcialmente en el estado líquido, pero se reforman en el estado vidrio.
- Fabricó con éxito películas delgadas alineadas y cristales de monolito a través de transiciones de fase controladas.
Conclusiones:
- Los polímeros de coordinación pueden someterse a fusión reversible y resolidificación.
- El comportamiento de "fusión" se atribuye a la composición equilibrada, la ionicidad y la fuerza de enlace.
- Esta transición de fase proporciona una nueva ruta para la fabricación de materiales funcionales basados en CP con arquitecturas controladas.
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