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Exitosa polimerización de dispersión en CO2 supercrítico utilizando surfactantes de hidrocarburos polivinilquilados
Hyunsuk Lee1, Elaine Terry, Mengmeng Zong
1School of Chemistry, The University of Nottingham, Nottingham NG7 2RD, United Kingdom.
Journal of the American Chemical Society
|August 22, 2008
Resumen
Las nuevas moléculas de hidrocarburos exhiben una solubilidad superior en dióxido de carbono supercrítico (scCO2). Este avance permite una polimerización de dispersión eficiente en scCO2, produciendo partículas de polímero bien definidas.
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 verde es la química verde.
Sus antecedentes:
- El dióxido de carbono supercrítico (scCO2) es un disolvente ecológico con propiedades sintonizables.
- El desarrollo de polímeros CO2-fílicos es crucial para expandir las aplicaciones de scCO2 en la polimerización.
- Los polímeros de hidrocarburos existentes tienen una solubilidad limitada en scCO2.
Objetivo del estudio:
- Para sintetizar nuevos polímeros de hidrocarburos CO2-fílicos. para sintetizar nuevos polímeros de hidrocarburos CO2-fílicos. para sintetizar nuevos polímeros de hidrocarburos CO2-fílicos. para sintetizar nuevos polímeros de hidrocarburos CO2-fílicos.
- Para investigar la solubilidad de estos polímeros en scCO2.
- Demostrar la utilidad de estos polímeros en la polimerización de dispersión dentro de scCO2.
Principales métodos:
- Para la síntesis se empleó la polimerización de adición-fragmentación-cadena de transferencia (RAFT) reversible.
- Los alquilados de poli (o vinilo) fueron diseñados para ser CO2-fílicos.
- La polimerización por dispersión de N-vinilpirrolidona se realizó en scCO2 utilizando los polímeros sintetizados como estabilizadores.
Principales resultados:
- Los polialquilados de vinilo sintetizados demostraron una solubilidad sin precedentes en scCO2.
- El grupo final de tiocarbonolitio facilitó el anclaje efectivo.
- Se obtuvieron altos rendimientos de partículas de polímero esférico bien definidas mediante polimerización por dispersión en scCO2.
Conclusiones:
- Se sintetizaron con éxito nuevos polímeros CO2-fílicos con una excepcional solubilidad en scCO2.
- Los polímeros desarrollados son estabilizadores efectivos para la polimerización de dispersión en scCO2.
- Este trabajo amplía el potencial de usar scCO2 como medio de reacción para la síntesis de polímeros.
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