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Las nanopartículas de polímero supramoleculares metastables a través del colapso intramolecular de cadenas de
E Johan Foster1, Erik B Berda, E W Meijer
1Institute for Complex Molecular Systems and Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|May 2, 2009
Resumen
Los investigadores desarrollaron un nuevo método para crear nanopartículas poliméricas utilizando el enlace cruzado activado por luz. Esta técnica permite la fabricación de nanopartículas bien definidas a partir de polímeros lineales sin procedimientos complejos de disolventes.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La fabricación de nanopartículas poliméricas bien definidas a menudo requiere técnicas complejas y selectivas de disolventes.
- El desarrollo de métodos fáciles para la síntesis de nanopartículas es crucial para las aplicaciones de materiales avanzados.
Objetivo del estudio:
- Introducir un método novedoso, activado por la luz, para sintetizar nanopartículas poliméricas.
- Para crear materiales supramoleculares capaces de formar nanopartículas a través del enlace cruzado intramolecular.
Principales métodos:
- Utilizando una fracción protegida de 2-ureido-pirimidinonona con un grupo o-nitrobenzil para crear un motivo latente de enlace cuadruplo de hidrógeno.
- La incorporación de este motivo en el lineal poly ((norbornenes).
- Inducir el enlace cruzado intramolecular y la formación de nanopartículas tras la irradiación de luz UV.
Principales resultados:
- Demostró un método fácil para fabricar nanopartículas poliméricas con una estrecha polidispersidad.
- Se confirmó la formación y las características de las partículas utilizando microscopía de fuerza atómica.
- Se han creado nanopartículas metastables a través de enlaces cruzados intramoleculares no covalentes reversibles.
Conclusiones:
- Este enfoque ofrece un método sin disolventes y activado por luz para la síntesis de nanopartículas.
- Las nanopartículas resultantes imitan biomacromoléculas plegadas, uniendo polímeros sintéticos y biopolímeros.
- Este trabajo representa un paso significativo hacia la integración de sistemas macromoleculares sintéticos y biológicos.
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