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Bicyclohexene-peri-naftalenes: síntesis escalable, funcionalidad diversa, polimerización eficiente y fácil
Jinghui Yang1, Maggie Horst1, Sabrina H Werby1
1Department of Chemistry, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|August 14, 2020
Resumen
Los investigadores desarrollaron nuevos polímeros que cambian de estados no conjugados a conjugados con fuerza mecánica. Estos nuevos mecanóforos ofrecen propiedades sintonizables y pueden ser activados por acciones mecánicas simples.
Área de la Ciencia:
- Química de los polímeros
- Ciencias de los materiales
- Química orgánica
Sus antecedentes:
- El desarrollo de polímeros con propiedades sintonizables bajo estímulos externos es un área de investigación clave.
- Los mecanóforos que sufren cambios significativos en las propiedades por estrés mecánico son muy buscados.
Objetivo del estudio:
- Para sintetizar y caracterizar una nueva clase de monómeros mecanóforos de tipo escalera, el biciclo[2.2.0]hex-5-ene-peri-naftaleno (BCH-Naph).
- Explorar la polimerización de los monómeros BCH-NAPH a través de la polimerización por metástasis de apertura de anillo (ROMP) y su posterior activación mecánica en polímeros conjugados.
Principales métodos:
- Síntesis de monómeros de BCH-NAPH en cantidades de varios gramos.
- Funcionalización de los monómeros BCH-Naph con varios sustituyentes.
- La polimerización por metástasis de apertura de anillo (ROMP) para producir poli-BCH-NAPH de muy alto peso molecular.
- Activación mecánica (ultrasonido, molienda, agitación) de las poli (BCH-NAPH).
Principales resultados:
- Los monómeros BCH-Naph se polimerizan eficientemente por ROMP, produciendo polímeros con pesos moleculares controlados y baja dispersión.
- Los poli-BCH-NAPH sintetizados pueden ser activados mecánicamente para transformarse en polímeros conjugados.
- La mecanoactivación conduce a cambios observables en las propiedades de absorción y fluorescencia.
- Las propiedades optoelectrónicas y físicas se pueden ajustar funcionalizando los monómeros BCH-Naph.
Conclusiones:
- Poly ((BCH-Naph) representan un sistema polimecanóforo versátil con propiedades sintonizables.
- La escalabilidad sintética, la diversidad funcional, la polimerización eficiente y la fácil mecanización hacen que este sistema sea atractivo para futuras investigaciones.
- Estos polímeros ofrecen potencial para explorar respuestas mecánicas multifacéticas tanto en la solución como en los estados sólidos.
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