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Solubilidad fase-selectiva del poli (N-alquilacrilamida) s
David E Bergbreiter1, Reagan Hughes, Jacqueline Besinaiz
1Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, TX 77842-3012, USA. bergbreiter@tamu.edu
Journal of the American Chemical Society
|July 3, 2003
Resumen
Las poli (N-alquilacrilamida) muestran una notable solubilidad de fase selectiva en mezclas de disolventes termomórficos. El ajuste de la longitud de la cadena N-alquilo controla con precisión la partición del polímero entre las fases del disolvente polar y no polar.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Las poli-N-alquilacrilamidas (PNA) son polímeros versátiles con propiedades sintonizables.
- Los sistemas de solventes termomórficos ofrecen oportunidades únicas para la manipulación selectiva de polímeros.
- La comprensión de la solubilidad por fase selectiva es crucial para el diseño de materiales avanzados.
Objetivo del estudio:
- Para investigar la solubilidad fase-selectiva de poli (N-alquilacrilamida) s en mezclas de disolventes termomórficos.
- Para establecer relaciones estructura-propiedad basadas en la longitud de la cadena N-alquilo.
- Para demostrar un enfoque de síntesis pool-split para la creación de bibliotecas PNA.
Principales métodos:
- Espectroscopia UV-vis y de fluorescencia para la determinación de la solubilidad.
- La síntesis pool-split utiliza un precursor de poli (N-acriloxisuccinimida) y también un precursor de poli (N-acriloxisuccinimida).
- Mediciones de solubilidad en una mezcla termomórfica de heptano/90% EtOH-H2O a 25°C.
Principales resultados:
- Se observaron solubilidades selectivas de fase altas (>10000:1) para PNAs representativos.
- Poly ((N-pentylacrylamide) mostró una solubilidad selectiva (>99.5%) en la fase polar rica en EtOH.
- Los PNA con cadenas N-alquilo más largas (C6 y superiores) se dividen preferentemente en la fase rica en heptano no polar.
Conclusiones:
- La longitud de la cadena N-alquilo es un determinante crítico de la solubilidad fase-selectiva del PNA.
- Los sistemas de disolventes termomórficos permiten un control preciso de la localización del polímero.
- Este trabajo proporciona una base para el diseño de materiales basados en PNA con comportamiento de fase a medida.
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