Rheological study of new dispersions of Carbon Nanotubes in the ionic liquid 1-ethyl-3-methylimidazolium dicyanamide

Dispersions of three different types of carbon nanotubes in a 1 wt.% proportion in the low viscosity 1-ethyl-3-methylimidazolium ([EMIM][DCA]) ionic liquid have been obtained. The neat ionic liquid presents Newtonian behavior, but the addition of carbon nanotubes increases the viscosity with respect...

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Detalles Bibliográficos
Autores: Avilés González, María Dolores, Pamies Porras, Ramón Francisco, Arias Pardilla, Joaquín, Carrión Vilches, Francisco José, Bermúdez Olivares, María Dolores, Sanes Molina, José
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2019
País:España
Institución:Universidad Politécnica de Cartagena(UPCT)
Repositorio:Repositorio Digital UPCT
OAI Identifier:oai:repositorio.upct.es:10317/7559
Acceso en línea:http://hdl.handle.net/10317/7559
Access Level:acceso abierto
Palabra clave:Carbon Nanotubes
ionic liquid
rheology
viscoelasticity
Raman
non-Newtonian fluids.
Ionic liquid
Viscoelasticity
Non-Newtonian fluids
Ciencia de los Materiales e Ingeniería Metalúrgica
3312 Tecnología de Materiales
Descripción
Sumario:Dispersions of three different types of carbon nanotubes in a 1 wt.% proportion in the low viscosity 1-ethyl-3-methylimidazolium ([EMIM][DCA]) ionic liquid have been obtained. The neat ionic liquid presents Newtonian behavior, but the addition of carbon nanotubes increases the viscosity with respect to [EMIM][DCA] in the following order: Single-Walled Carbon Nanotubes (SWCNTs) > aligned Multi-Walled Carbon Nanotubes (aligned-MWCNTs) > Multi-Walled Carbon Nanotubes (MWCNTs), and the resulting fluids show non-Newtonian behavior. SWCNTs and MWCNTs dispersions present shear thinning with increasing shear rate, but a shear thickening effect for aligned-MWCNTs at intermediate shear rate values at room temperature has been observed. This effect disappears at 100 ºC. The thermal response of the viscosity of [EMIM][DCA] and the CNTs-IL dispersions can be fitted to the Arrhenius model. For[EMIM][DCA] and the dispersion with MWCNTs the viscous behavior prevails at low frequencies, with a cross point at a critical frequency value which decreases with increasing temperature. However, the dispersions of SWCNTs and aligned-MWCNTspresent storage modulus values higher than loss modulus in the whole range of frequency.