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Redes adaptables covalentes que utilizan ésteres β-amino como bloques de construcción térmicamente reversibles

Christian Taplan¹, Marc Guerre^1,2, Filip E Du Prez¹

¹Polymer Chemistry Research Group, Center of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Faculty of Science, Ghent University, Krijgslaan 281 S4-bis, Ghent B-9000, Belgium.

Journal of the American Chemical Society

|June 14, 2021

Resumen

Este estudio introduce las redes dinámicas covalentes adaptables (CAN) utilizando ésteres β-amino. Estos materiales adaptables son reprocesables y presentan una excelente estabilidad térmica y resistencia al deslizamiento, incluso a altas temperaturas.

Área de la Ciencia:

Química de los polímeros
Ciencias de los materiales
Química orgánica

Sus antecedentes:

Los ésteres β-amino son típicamente aductos estables, no bloques de construcción dinámicos.
La química covalente dinámica permite la autocuración y el reprocesamiento de los materiales.
El desarrollo de redes adaptables con propiedades sintonizables es un desafío clave.

Objetivo del estudio:

Investigar los ésteres β-amino como bloques de construcción para las redes dinámicas covalentes (CAN).
Demostrar los mecanismos de intercambio dinámico dual (aza-Michael y transesterificación) en estas redes.
Para crear materiales reprocesables de alto rendimiento con propiedades térmicas ajustables.

Principales métodos:

Síntesis de ésteres β-amino a través de la adición aza-Michael.
Estudios cinéticos para elucidar los mecanismos dinámicos de intercambio covalente.
Formulación y caracterización de los CAN basados en el β-amino éster.
Reprocesamiento y evaluación de las propiedades (Tg, resistencia al deslizamiento) de las CAN.

Principales resultados:

Los ésteres β-amino muestran un intercambio covalente dinámico a través de la reacción de aza-Michael y la transesterificación libre de catalizadores.
Los CAN desarrollados son reprocesables a través de estos mecanismos dinámicos duales.
Los materiales presentan una amplia gama de temperaturas de transición de vidrio (-60 a 90 °C) y una alta resistencia al deslizamiento.
Reprocesamiento mejorado (hasta 10 ciclos a 150 °C) obtenido con bloques de construcción que contienen β-hidroxilo.

Conclusiones:

Los ésteres β-amino son bloques de construcción versátiles para crear redes dinámicas covalentes adaptables.
Los mecanismos de intercambio dinámico dual permiten un reprocesamiento robusto y propiedades de material ajustables.
Estas redes adaptables ofrecen una plataforma prometedora para materiales sostenibles y de alto rendimiento.

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