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¿Qué tan fluoro es el poli-2,2-bis-trifluorometil-4,5-difluoro-1,3-dióxido-co-tetrafluoroetileno (Teflon AF)?
Hong Zhao1, Kamal Ismail, Stephen G Weber
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
Journal of the American Chemical Society
|October 14, 2004
Resumen
Las películas de teflón AF 2400, cuando se exponen a disolventes como el cloroformo, se plastifican, aumentando significativamente la difusión del soluto. Este polímero fluoro es un polímero fluoro.
Área de la Ciencia:
- La ciencia de los polímeros es la ciencia de los polímeros.
- Ciencia de los materiales ciencia de los materiales.
- Ingeniería química Ingeniería química.
Sus antecedentes:
- El Teflón AF 2400 es un polímero fluorocíclico estable y permeable.
- Su potencial como medio de transporte/extracción de solutos no ha sido explorado.
Objetivo del estudio:
- Investigar el teflón AF 2400 como un nuevo medio de transporte/extracción.
- Comprender la influencia de la exposición al disolvente en sus propiedades de transporte.
Principales métodos:
- Estudió el comportamiento de transporte de varios solutos en solución de cloroformo a través de películas de Teflón AF 2400.
- Se midió la partición y difusión del benceno en la película de polímero.
- Se investigaron los efectos de plastificación de Krytox FSH en las películas de teflón AF 2400.
Principales resultados:
- El cloroformo se absorbe en altas concentraciones (1,13 M), plastificando la película.
- El coeficiente de difusión del benceno aumentó en 3 órdenes de magnitud en películas equilibradas con cloroformo.
- La partición de la 3-hidroxipiridina en el soluto polar fue afectada significativamente por el medio.
- Krytox FSH plastificó las películas, disminuyendo Tg a -40°C y permitiendo el reconocimiento molecular.
- La asociación no covalente con Krytox FSH aumentó la proporción de distribución de 3-hidroxipiridina en 41 veces.
Conclusiones:
- Las propiedades de transporte del teflón AF 2400 dependen en gran medida de la exposición al disolvente.
- La sorción del disolvente plastifica el polímero, mejorando la difusión del soluto.
- La naturaleza fluorescente de las películas de Teflón AF 2400 se reduce con la inhibición de disolventes orgánicos.
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