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Fenotiazinas conjugadas enlazadas como fotocatalizadores heterogéneos de luz verde o roja para la polimerización

Sajjad Dadashi-Silab¹, Francesca Lorandi¹, Matthew J DiTucci²

¹Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States.

Journal of the American Chemical Society

|June 21, 2021

Resumen

Los polímeros microporosos conjugados (CMP) aprovechan la luz visible para la síntesis controlada de polímeros a través de la polimerización radical de transferencia atómica fotoinducida (ATRP). Este fotocatalizador reutilizable polimeriza eficientemente los monómeros utilizando luz verde o roja.

Área de la Ciencia:

Química de los polímeros
Ciencias de los materiales
Fotocatálisis

Sus antecedentes:

Las técnicas de polimerización radical controlada como la polimerización radical de transferencia atómica (ATRP) son cruciales para sintetizar polímeros bien definidos.
El ATRP tradicional inducido por la luz a menudo se basa en la luz UV, lo que limita su alcance de aplicación.
El desarrollo de sistemas que utilicen luz visible para ATRP es esencial para una mayor aplicabilidad y una síntesis más ecológica.

Objetivo del estudio:

Desarrollar nuevos fotocatalizadores heterogéneos para el ATRP catalizado por cobre impulsado por luz visible.
Utilizar polímeros microporosos conjugados (CMP) que incorporen fenotiazina (PTZ) para una fotoiniciación eficiente.
Para demostrar la polimerización controlada de los monómeros de acrilato y metacrilato bajo luz visible.

Principales métodos:

Síntesis de polímeros microporosos conjugados basados en fenotiazina (PTZ-CMP) mediante el enlace cruzado de Friedel-Crafts.
Caracterización de la fotoactividad PTZ-CMP en el espectro de luz visible.
Aplicación de PTZ-CMP como fotocatalizadores heterogéneos en ATRP catalizado por cobre bajo irradiación de luz verde o roja.

Principales resultados:

Los PTZ-CMP sintetizados mostraron fotoactividad en la región visible debido a la conjugación extendida.
Se logró una polimerización eficiente de los monómeros de acrilato y metacrilato con una alta conversión y pesos moleculares controlados.
El fotocatalizador heterogéneo demostró una fácil separación y reutilización para múltiples ciclos de polimerización.

Conclusiones:

El ATRP impulsado por luz visible puede ser mediado efectivamente por PTZ-CMP heterogéneos.
Este enfoque ofrece un método sostenible y eficiente para sintetizar polímeros bien definidos.
El sistema fotocatalizador desarrollado es prometedor para aplicaciones prácticas en la síntesis de polímeros y la ciencia de los materiales.

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