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Autoensamblaje inducido por polimerización/depolimerización bajo equilibrios acoplados de polimerización con
Jiyun Nam1, Changsu Yoo1, Myungeun Seo1,2
1Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Journal of the American Chemical Society
|May 8, 2024
Resumen
El control dinámico de las cadenas de polímeros a través de la polimerización y la despolimerización reversibles permite el autoensamblaje desencadenado por la temperatura de los copolímeros de bloque en materiales blandos sintonizables.
Área de la Ciencia:
- Química de los polímeros
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- La despolimerización ofrece una ruta sostenible para descomponer los polímeros en monómeros.
- La polimerización y la despolimerización reversibles se pueden controlar por la temperatura.
- El autoensamblaje de los copolímeros de bloque es crucial para crear nanoestructuras.
Objetivo del estudio:
- Demostrar el control dinámico sobre el autoensamblaje del copolímero en bloque mediante la polimerización/despolimerización reversible.
- Investigar las transiciones morfológicas reversibles inducidas por la temperatura en los nanoobjetos.
- Explorar el potencial de estos sistemas dinámicos como materiales blandos.
Principales métodos:
- Se utiliza la polimerización de apertura de anillo de la δ-valerolactona iniciada a partir del óxido de polietileno.
- Se emplean ciclos de temperatura para inducir la polimerización/depolimerización/repolimerización.
- Estudió las transiciones morfológicas de los nanoobjetos micelares de copolímero de bloque en disolventes selectivos.
Principales resultados:
- Se ha logrado un control reversible sobre el autoensamblaje del copolímero de bloque mediante cambios de temperatura.
- Se han demostrado transiciones morfológicas reversibles (por ejemplo, varilla-esfera-varilla, fibra-varilla-fibra) mediante la regulación del parámetro de embalaje.
- Se observó que la selectividad del disolvente aumenta la despolimerización a temperaturas más bajas debido a los efectos entrópicos.
Conclusiones:
- El autoensamblaje inducido por polimerización / despolimerización (PDISA) ofrece un nuevo método para la formación dinámica de nanoobjetos.
- Se lograron con éxito cambios morfológicos sensibles a la temperatura en las micelas de copolímero de bloque.
- Estos materiales blandos dinámicos exhiben potencial para aplicaciones que requieren propiedades macroscópicas ajustables como la viscosidad.
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