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Plasticidad fotoinducida en polímeros reticulados
Timothy F Scott1, Andrew D Schneider, Wayne D Cook
1Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO 80309, USA.
Science (New York, N.Y.)
|June 11, 2005
Resumen
Los polímeros químicamente reticulados ahora pueden relajar el estrés y la tensión durante la exposición a la luz sin perder la integridad del material. Este avance permite la plasticidad fotoinducida y cambios de forma en materiales poliméricos avanzados.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los polímeros químicamente entrelazados enfrentan limitaciones debido a las tensiones internas de los cambios de volumen durante la polimerización.
- La modificación de la forma de los polímeros reticulados a menudo conduce a la degradación de las propiedades o a la acumulación de tensiones.
Objetivo del estudio:
- Desarrollar un nuevo polímero reticulado capaz de la tensión y la relajación de la tensión desencadenada por la luz.
- Para lograr la modificación de la forma sin comprometer las propiedades del material.
Principales métodos:
- Introducción de radicales a través de la fotoescisión del fotoiniciador residual dentro de la matriz del polímero.
- Utilizando la transferencia de cadena de adición-fragmentación de grupos funcionales de la cadena media para la difusión radical.
- Emplear la luz como un estímulo externo para iniciar procesos de relajación.
Principales resultados:
- Demostración de estrés inducido por la luz y/o relajación de la deformación en polímeros reticulados.
- Preservación de las propiedades del material durante la relajación fotoinducida.
- Se logra la plasticidad fotoinducida, la activación y los cambios de forma de equilibrio sin estrés residual.
Conclusiones:
- El polímero desarrollado exhibe plasticidad fotoinducida, lo que permite la manipulación de la forma sin estrés.
- Esta tecnología es crucial para aplicaciones en microdispositivos, biomateriales y recubrimientos avanzados.
- La generación y difusión de radicales desencadenados por luz ofrecen una nueva vía para el control dinámico de la red de polímeros.
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