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Estereocomplejos robustos y complejos de inclusión C60 de polímeros estereorregulados funcionalizados con vinilo
Fernando Vidal1, Laura Falivene2, Lucia Caporaso3
1Department of Chemistry, Colorado State University , Fort Collins, Colorado 80523-1872, United States.
Journal of the American Chemical Society
|July 9, 2016
Resumen
Se sintetizaron polímeros de vinilo polar altamente sindiotácticos utilizando una nueva polimerización de coordinación. Estos polímeros forman complejos estereomoléculares supramoleculares robustos y entrelazados y complejos de inclusión C60 con propiedades mejoradas.
Área de la Ciencia:
- Química de los polímeros
- Química supramolecular
- Ciencias de los materiales
Sus antecedentes:
- El desarrollo de polímeros de vinilo polar con estereoquímica controlada es un desafío.
- Los métodos existentes carecen de quimioselectividad y sindiospecificidad para los monómeros diviniles polares.
Objetivo del estudio:
- Para sintetizar polímeros polares de vinilo altamente sindiotácticos.
- Construir complejos estereomoléculares robustos y de inclusión de C60.
Principales métodos:
- Polimerización de coordinación mediada por metales de monómeros diviniles (VMA, AMA, DAA) mediante el uso de catalizadores enolados de éster de circonocenio ligado al Cs.
- Investigaciones experimentales (sintéticas, cinéticas, mecanicistas) y teóricas (DFT).
- Posfuncionalización a través de reacciones de clic de tioleno y fotocurado.
Principales resultados:
- Se obtiene una quimioselectividad completa y una alta sindiotáctica (> 99% rr) en la síntesis de polímeros.
- Construcción demostrada de complejos estereoscópicos cristalinos supramoleculares y complejos de inclusión C60.
- Se han desarrollado complejos estereoscópicos resistentes a los disolventes con propiedades térmicas y mecánicas mejoradas.
Conclusiones:
- La nueva polimerización de coordinación permite la síntesis de polímeros de vinilo polares sindiotácticos controlados con precisión.
- Estos polímeros sirven como bloques de construcción versátiles para materiales supramoleculares avanzados.
- Los complejos reticulados resultantes exhiben características de rendimiento superiores.
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