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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
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Polímeros controlados por secuencia a través de la polimerización de metástasis de apertura de anillo impulsada por
Jamie A Nowalk1, Cheng Fang1,2, Amy L Short1
1Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States.
Journal of the American Chemical Society
|February 5, 2019
Resumen
La síntesis de poliésteres secuenciados ahora es escalable y controlable utilizando la polimerización de metástasis de apertura de anillo mejorada por selectividad (SEED-ROMP). Este método permite un control preciso del peso molecular y las propiedades del polímero, superando las limitaciones anteriores.
Área de la Ciencia:
- Química de los polímeros
- Ciencias de los materiales
Sus antecedentes:
- La secuencia de monómeros influye críticamente en las propiedades de los copolímeros, pero la síntesis controlada de los copolímeros secuenciados es un desafío.
- Los métodos previos de crecimiento por etapas para el ácido policlórico secuenciado carecían de control de peso molecular, escalabilidad y previsibilidad de rendimiento.
Objetivo del estudio:
- Desarrollar un método eficiente, escalable y controlable para la síntesis de poliésteres secuenciados.
- Investigar el impacto de la secuencia de monómeros en las propiedades del polímero utilizando una nueva técnica de polimerización.
Principales métodos:
- Síntesis de poliésteres secuenciados a través de la polimerización por metástasis de apertura de anillo impulsada por la entropía (ED-ROMP) de macronoméricos cíclicos.
- Incorporación de etileno glicol y enlaces de metástasis para el ED-ROMP.
- Preparación de macronomeros cíclicos mediante metástasis de cierre de anillo y macrolactonización.
- Utilización de cis-olefinas en el segmento activo de la metátesis para mejorar la selectividad (SEED-ROMP).
Principales resultados:
- Síntesis en escala multigrama de poliésteres secuenciados con pesos moleculares controlados.
- SEED-ROMP demostró cinética de primer orden y dispersiones estrechas, lo que indica un carácter vivo mejorado.
- Preparación exitosa de copolímeros de bloque, confirmando aún más la naturaleza viva de la polimerización.
- El análisis computacional reveló que las olefinas cis-macrocíclicas mejoran la cinética de la polimerización debido a las preferencias conformacionales.
Conclusiones:
- SEED-ROMP proporciona una estrategia general y eficaz para la producción de polímeros controlados por peso molecular con segmentos secuenciados incorporados con precisión.
- Este avance supera las limitaciones de los métodos anteriores, lo que permite aplicaciones más amplias en la ciencia de los polímeros.
- Los hallazgos allanan el camino para el diseño de polímeros con propiedades a medida a granel a través de la secuenciación controlada.
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