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Autoensamblaje inducido por cristalización de polimerización asimétrica de polímeros de bloques helicoidales y de

Randall A Scanga¹, Ali Shahrokhinia¹, Jake Borges¹

¹Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States.

Journal of the American Chemical Society

|March 13, 2023

Resumen

Este estudio introduce el autoensamblaje impulsado por cristalización inducida por polimerización asimétrica (A-PI-CDSA) para crear nanoestructuras quirales sintonizables a partir de copolímeros de bloque de bobina de varilla. El nuevo método permite la síntesis escalable de diversas morfologías helicoidales con tamaño y forma controlados.

Área de la Ciencia:

Ciencia e ingeniería de polímeros
Química de los materiales
Nanotecnología

Sus antecedentes:

Los copolímeros de bloque (BCP) son cruciales para la creación de nanoestructuras.
El control de la quiralidad y la morfología en los BCP autoensamblados sigue siendo un desafío.
Los métodos existentes a menudo carecen de escalabilidad y control preciso sobre las dimensiones de la nanoestructura.

Objetivo del estudio:

Para combinar el autoensamblaje impulsado por la cristalización inducida por polimerización (PI-CDSA) con el autoensamblaje BCP helicoidal de bobina de varilla.
Desarrollar un PI-CDSA asimétrico (A-PI-CDSA) para la síntesis escalable y controlable in situ de nanoestructuras quirales.
Explorar la formación de nanoestructuras quirales de forma, tamaño y dimensión variables.

Principales métodos:

Desarrollo de PI-CDSA asimétrico (A-PI-CDSA) para BCPs quirales y en espiral (poliariloisocianuro) - PAIC y polietilenglicol - PEG).
Macroiniciadores basados en níquel PEG utilizados para la síntesis y el autoensamblaje de BCP.
Investigó el A-PI-CDSA "vivo" para las nanofibras en 1D y la nucleación/crecimiento espontáneo para las nanohojas en 2D; exploró el A-PI-CDSA "semeado" en 2D para las estructuras jerárquicas.

Principales resultados:

Se ha logrado la síntesis escalable de nanoestructuras quirales PAIC-BCP con morfologías sintonizables a un 5,0-10% de peso de los sólidos.
Se ha demostrado la formación de nanofibras quirales 1D con longitudes controlables y nanohojas hexagonales uniformes.
Reveló un nuevo paradigma con morfologías de espiral jerárquicamente quirales (helicoides hexagonales) ajustadas al tamaño en 3D a través de A-PI-CDSA sembrado, que exhiben una actividad quiróptica amplificada (factores g hasta -0.030).

Conclusiones:

A-PI-CDSA proporciona una plataforma versátil para la síntesis escalable in situ de nanoestructuras quirales complejas.
El método permite un control preciso de la dimensionalidad, el tamaño y la morfología de la nanoestructura.
Este enfoque abre nuevas vías para el diseño de materiales quirales avanzados con propiedades quirópticas sintonizables.

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