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La polimerización de dispersión acuosa: un nuevo paradigma para el autoensamblaje de copolímero de bloque in situ en

Shinji Sugihara¹, Adam Blanazs, Steven P Armes

¹Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan.

Journal of the American Chemical Society

|August 23, 2011

Resumen

Este estudio detalla un nuevo método para crear nanopartículas de polímero en el agua utilizando la polimerización de transferencia de cadena de adición-fragmentación reversible. Los investigadores controlan con precisión la forma de las nanopartículas, como esferas, gusanos o vesículas, ajustando la composición y la concentración del polímero.

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.
Nanotecnología La nanotecnología es la nanotecnología.

Sus antecedentes:

Las técnicas de polimerización radical controlada son cruciales para la síntesis de polímeros bien definidos.
La polimerización por dispersión acuosa ofrece una ruta ecológica hacia los nanomateriales.
El diseño de copolímeros de bloque con morfologías específicas requiere un control preciso de la composición del bloque.

Objetivo del estudio:

Desarrollar un método reproducible para sintetizar nanopartículas de copolímero diblock en solución acuosa.
Para dilucidar el diagrama de fase que rige la morfología de las partículas.
Para controlar la formación de esferas, gusanos o vesículas a través de parámetros de polimerización.

Principales métodos:

Utilizando la polimerización de transferencia de cadena de adición-fragmentación reversible (RAFT, por sus siglas en inglés).
Empleando un agente de transferencia de la cadena macromolecular de poli-metiloiloiloiloxietilfosforilcolina (PMPC) soluble en agua.
Conduciendo la polimerización por dispersión acuosa del metacrilato de 2-hidroxipropilo (HPMA).

Principales resultados:

Se estableció un diagrama de fase detallado, que predice la morfología de las partículas basándose en la composición de los bloques.
Se logró una síntesis fácil, eficiente y reproducible de esferas de copolímero diblock, gusanos o vesículas.
La morfología de las partículas (esferas, gusanos, vesículas) fue controlada por el grado objetivo de polimerización del bloque hidrofóbico y la concentración de sólidos.

Conclusiones:

Esta estrategia permite la preparación directa de nanoestructuras bien definidas de copolímero diblock en una solución acuosa concentrada.
La polimerización de HPMA en un macroiniciador PMPC impulsa el autoensamblaje en varias morfologías.
El estudio proporciona un enfoque sistemático para controlar la forma de las nanopartículas para aplicaciones de materiales avanzados.

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