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Interacción compuesta del control cinético y termodinámico sobre las secuencias de comonomeros por polimerización de
Liam T Reilly1, Michael L McGraw1, Francesca D Eckstrom1
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States.
Journal of the American Chemical Society
|December 15, 2022
Resumen
El control de secuencia compuesto (CSC) a través de la polimerización por pares de Lewis (LPP) dicta con precisión las secuencias de copolímero de bloque (BCP) equilibrando los parámetros termodinámicos y cinéticos. Este método expande el alcance del monómero y mejora el control de la arquitectura del polímero.
Área de la Ciencia:
- Química de los polímeros
- Ciencias de los materiales
- Síntesis orgánica
Sus antecedentes:
- La polimerización directa de mezclas de comonomeros ofrece una síntesis eficiente de copolímeros de bloque (BCP).
- Los métodos tradicionales a menudo carecen de control sobre la secuencia de copolímero y el alcance del monómero.
- El control de secuencia compuesto (CSC) por polimerización de pares de Lewis (LPP) ofrece un control mejorado.
Objetivo del estudio:
- Investigar la interacción entre los parámetros termodinámicos (Keq) y cinéticos (kp) en el CSC-LPP.
- Para demostrar el control preciso de las secuencias de comonomeros en los monómeros polares de vinilo.
- Para permitir la síntesis de avanzadas arquitecturas de copolímero de bloque.
Principales métodos:
- Cuantificación experimental de los parámetros del equilibrio ácido de Lewis (Keq) y la tasa de polimerización (kp) para varios monómeros.
- Validación computacional de los datos cinéticos y termodinámicos.
- Diseño y ejecución de copolimizaciones para estudiar la relación Keq-kp.
- Análisis de las microestructuras de copolímero resultantes.
Principales resultados:
- Se estableció una comprensión cuantitativa de los parámetros Keq y kp para diversos monómeros.
- Demostró un control preciso sobre las secuencias de comonomeros, suprimiendo errores como el estrechamiento y la incorporación errónea.
- Relaciones correlacionadas Keq-kp con las microestructuras de copolímero resultantes.
- Copolímeros de bloque de orden superior sintetizados.
Conclusiones:
- CSC-LPP proporciona una plataforma poderosa para el control preciso de la secuencia BCP.
- La metodología permite el diseño racional de arquitecturas complejas de polímeros.
- Este enfoque facilita la innovación de materiales a través de la polimerización controlada.
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