Alignment of hexatic langmuir monolayers under shear

We have studied the structural changes that fatty acid monolayers in the Ov phase undergo when a simple shear flow is imposed. A strong coupling is revealed by the changes in domain structure that are observable using Brewster angle microscopy, suggesting the possibility of shear alignment. The depe...

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Detalles Bibliográficos
Autores: Ignés i Mullol, Jordi, Schwartz, Daniel K.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2000
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/13259
Acceso en línea:https://hdl.handle.net/2445/13259
Access Level:acceso abierto
Palabra clave:Pel·lícules fines
Reologia
Química de superfícies
Thin films
Rheology
Surface chemistry
Descripción
Sumario:We have studied the structural changes that fatty acid monolayers in the Ov phase undergo when a simple shear flow is imposed. A strong coupling is revealed by the changes in domain structure that are observable using Brewster angle microscopy, suggesting the possibility of shear alignment. The dependence of the alignment on the molecular polar tilt proves that the mechanism is different than in nematic liquid crystals. We argue that the degenerate lattice symmetry lines of the underlying pseudohexagonal lattice align in the flow direction, and we explain the observed alignment angle using geometrical arguments.