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Título del libro: Self-Assembled Supramolecular Architectures: Lyotropic Liquid Crystals
Título del capítulo: Rheological Theory and Simulation of Surfactant Nematic Liquid Crystals

Autores UNAM:
EDTSON EMILIO HERRERA VALENCIA;
Autores externos:

Idioma:
Inglés
Año de publicación:
2012
Palabras clave:

Applications to surfactant nematic liquid crystals; Computer simulation of lyotropic nematic, LE and Landau-de Gennes; Nematic liquid crystal flow modeling, nematic and wormlike; Rheological theory and surfactant nematic liquid crystal simulation; Theo


Resumen:

This chapter presents a comprehensive review of rheological theory, modeling, and simulation of surfactant nematic liquid crystalline phases, including calamitic and discotic micellar solutions and wormlike micelles. A review of verifi able rheological liquid crystal models for lyotropic nematics highlighting the mechanisms that control orientation behavior under shear, anisotropic viscoelasticity, and non-Newtonian behavior. Since defects and textures are essential characteristics of these materials that affect the fl ow properties, an in-depth review of physical and rheophysical defects is presented, including defect nucleation and coarsening processes. The theory for micellar nematicsis applied to textures, fl ow birefringence, phase transition under shear, orientation fl uctuations, and fl ow alignment, and the predictions are compared with experimental data. The theory is fi nally applied to transient shear fl ows of wormlike micellar nematic solutions, and the predicted banded textures and transient stress responses are compared to rheological experiments. The predictions provide a new way to extract additional information from experimental rheological data and allow to distinguish the role of liquid crystalline properties such as viscoelastic anisotropy, fl ow alignment, couplingbetween orientation kinematics, and fl ow kinematics. The rheological predictions show a strong similarity with other nematic materials, including low-molar-mass thermotropes and lyotropic nematic polymers. © 2012 John Wiley and Sons, Inc.


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