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Las fuerzas capilares en la reología de la suspensión
Erin Koos1, Norbert Willenbacher
1Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany. erin.koos@kit.edu
Science (New York, N.Y.)
|February 19, 2011
Resumen
La adición de un fluido inmiscible secundario a las suspensiones altera drásticamente la reología, creando redes de partículas y comportamiento similar al gel. Este fenómeno universal mejora la estabilidad de la suspensión y ofrece aplicaciones potenciales en la ciencia de los materiales.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La dinámica de fluidos es la dinámica de fluidos.
- Ciencia de la coloide Ciencia de las coloides.
Sus antecedentes:
- La reología de las suspensiones se controla típicamente por la fracción de volumen sólido.
- Las interacciones de partículas y la formación de redes influyen significativamente en las propiedades del bulto.
Objetivo del estudio:
- Investigar el efecto de la adición de un fluido secundario inmiscible en la reología de la suspensión.
- Explorar los mecanismos subyacentes de la formación de la red de partículas y su impacto en las propiedades de los materiales.
Principales métodos:
- Caracterización de varios sistemas de partículas y líquidos.
- Adición de pequeñas cantidades de un fluido secundario inmiscible.
- Mediciones reológicas para evaluar cambios en la viscosidad y la elasticidad.
Principales resultados:
- La adición secundaria de fluido induce la aglomeración de partículas a través de las fuerzas capilares.
- La formación de redes de partículas estables transforma las suspensiones de viscosas a altamente elásticas o parecidas a un gel.
- Este efecto es independiente de las propiedades de humedad del fluido secundario en relación con las partículas.
Conclusiones:
- Un fluido secundario inmiscible es una herramienta poderosa para controlar la reología de la suspensión.
- Las redes de partículas inducidas mejoran la estabilidad de la suspensión, evitando el asentamiento.
- Las aplicaciones potenciales incluyen precursores para espumas de polímero microporoso y cerámica ligera.
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