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Naturaleza de la tensión a nivel atómico en sistemas de polímeros densos
Science (New York, N.Y.)
|November 4, 1994
Resumen
Este estudio introduce el estrés intrínseco del monómero (IMS), un nuevo concepto a nivel atómico para comprender el estrés en sistemas de polímeros densos. IMS proporciona una medida independiente del tiempo de las contribuciones de los monómeros individuales al estrés macroscópico, aplicable a través de varios estados del polímero.
Área de la Ciencia:
- Física de los polímeros Física de los polímeros
- Ciencia de los materiales Ciencia de los materiales.
- Química computacional es la química computacional.
Sus antecedentes:
- Las teorías clásicas de la tensión del polímero se centran en los conceptos de resorte molecular y entrópico.
- Ha faltado una comprensión detallada a nivel atómico de la tensión en polímeros densos.
- Los modelos anteriores no captaron completamente las contribuciones localizadas al estrés macroscópico.
Objetivo del estudio:
- Desarrollar una nueva descripción a nivel atómico de la tensión en sistemas de polímeros densos.
- Introducir y definir el concepto de estrés intrínseco del monómero (IMS).
- Investigar el comportamiento y la aplicabilidad de IMS en diferentes condiciones de polímero.
Principales métodos:
- Se emplearon extensas simulaciones por computadora para analizar los sistemas de polímeros a nivel atómico.
- Se definió un nuevo sistema de coordenadas móviles locales para aislar las contribuciones individuales de monómeros.
- La tensión intrínseca del monómero (IMS) se calculó dentro de este marco.
Principales resultados:
- El estrés intrínseco del monómero (IMS) fue identificado como un parámetro clave, independiente del tiempo.
- El IMS cuantifica la contribución del monómero individual al estrés macroscópico general.
- El valor de IMS se mantiene consistente en fusiones de equilibrio, durante la relajación de la tensión y en sistemas de enlaces cruzados deformados a densidad fija.
Conclusiones:
- La tensión intrínseca del monómero (IMS) ofrece una nueva perspectiva fundamental sobre la tensión del polímero.
- IMS proporciona una métrica robusta e independiente del tiempo aplicable a diversos estados de polímeros.
- Este concepto a nivel atómico mejora la comprensión del comportamiento mecánico en polímeros densos.
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