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Mecanismo del proceso de autoensamblaje y la polimerización supramolecular sembrada del organogelador de perileno
Soichiro Ogi1, Vladimir Stepanenko, Kazunori Sugiyasu
1Institut für Organische Chemie and Center for Nanosystems Chemistry, Universität Würzburg , Am Hubland, 97074 Würzburg, Germany.
Journal of the American Chemical Society
|February 18, 2015
Resumen
Este estudio revela cómo las moléculas organogeladoras forman nanofibras a través de la polimerización supramolecular. El control de la cinética de nucleación a través de la histeresis térmica permite la polimerización viva, aplicable a varias estructuras nanofibrosas de autoensamblaje.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
Sus antecedentes:
- Las moléculas organogelétricas se autoensamblan en nanofibras unidimensionales.
- Comprender el mecanismo de la polimerización supramolecular es crucial para el diseño de materiales.
Objetivo del estudio:
- Para dilucidar el mecanismo de polimerización supramolecular para un arquetipo de organogelator.
- Identificar las condiciones para controlar la nucleación y lograr la polimerización viva.
Principales métodos:
- Se emplearon análisis termodinámicos y cinéticos.
- Investigó el efecto de la temperatura, el disolvente y la concentración en el autoensamblaje.
- Se utilizaron experimentos de polimerización con semillas.
Principales resultados:
- Se identificaron condiciones para retrasar la nucleación espontánea, causando tiempos de retraso de más de 1 hora.
- Se observó histeresis térmica en el proceso de nucleación, confirmando una cinética única.
- Se ha demostrado la polimerización supramolecular viva mediante la adición de semillas en condiciones específicas.
Conclusiones:
- La cinética de la polimerización supramolecular, en particular la nucleación, puede ser controlada.
- La polimerización con semilla es una estrategia viable para las estructuras nanofibrosas 1D.
- El control vivo de la polimerización supramolecular cooperativa de crecimiento de la nucleación se puede lograr a través de la histeresis térmica.
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