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Efectos de la estructura monomérica en su organización y polimerización en un cristal líquido smético
1C. A. Guymon, E. N. Hoggan, C. N. Bowman, Department of Chemical Engineering, University of Colorado, Boulder, CO 80309-0424, USA. N. A. Clark, Department of Physics, University of Colorado, Boulder, CO 80309-0390, USA. T. P. Rieker, Department of Chemical and Nuclear Engineering, Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, NM 87106, USA. D. M. Walba, Department of Chemistry, University of Colorado, Boulder, CO 80309-0215, USA.
Science (New York, N.Y.)
|January 3, 1997
Resumen
Los monómeros fotopolimerizables en cristales líquidos (LC) se autoensamblan en función de la estructura, lo que aumenta significativamente las tasas de polimerización. Este descubrimiento ofrece nuevas estrategias de diseño para materiales poliméricos avanzados.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Física de los cristales líquidos Física de los cristales líquidos
Sus antecedentes:
- Los cristales líquidos (LC) exhiben propiedades únicas de autoensamblaje.
- La fotopolimerización es un proceso clave en la síntesis de materiales.
- El control de la organización de los monómeros es crucial para las propiedades de los polímeros.
Objetivo del estudio:
- Para investigar la segregación espacial y la orientación de los monómeros de diacrilato fotopolimerizables en anfitriones de cristales líquidos smectic A y smectic C.
- Comprender cómo la estructura monomérica influye en su comportamiento dentro de las fases LC.
- Para determinar el impacto de este autoensamblaje en la cinética de la fotopolimerización.
Principales métodos:
- Disolviendo monómeros de diacrilato (por ejemplo, HDDA, C6M) en anfitriones de cristales líquidos smectic A y C.
- Utilizando técnicas para observar la segregación y orientación de monómeros.
- La medición de las tasas de fotopolimerización (propagación y terminación) en diferentes condiciones.
Principales resultados:
- La estructura monomérica dicta la segregación espacial y la orientación dentro de las capas de LC.
- Los monómeros pequeños y flexibles (HDDA) se intercalaban paralelamente a las capas.
- Los monómeros en forma de vara (C6M) se alinean normalmente con las capas y se acumulan dentro de ellas.
- La estratificación esmética mejora drásticamente las tasas de fotopolimerización para ambos tipos de monómeros.
Conclusiones:
- Los anfitriones smectic LC inducen una organización monomérica significativa, que tiene un impacto en la polimerización.
- La adaptación de la estructura de monómeros permite el control de la cinética de autoensamblaje y polimerización.
- Estos hallazgos allanan el camino para el diseño de nuevos materiales en LCs de gel y polímeros separados por nanofase.
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