Investigation of surface effects on lytropic liquid crystals

• Grant number: 98/11044-7
• Support Opportunities: Regular Research Grants
• Start date: December 01, 1998
• End date: March 31, 2001
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Elisabeth Andreoli de Oliveira
• Grantee: Elisabeth Andreoli de Oliveira
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The aim of this Project is the investigation of the interactions in the interface of lyotropic liquid crystals. Different aspect of these interactions will be investigated; the molecular interactions between the substrate and the liquid crystal, the influence of the topology of the substrate and the influence of the dimensions Fo the system on its physical properties. In this study the substrates will be coated with thin films of polymers and photopolymers, where the conformation of the molecules can changed by rubbing, by recording a diffraction grating or by a photopolymerization process with UV polarized light. The influence of the symmetry of the surface on the resulting orientation of the liquid crystal will be analysed by using substrates microtextured, allowing a comparison between the strength of the bulk and surface interations. In confined geometries, where the surface effects are dominant, the critical behavior of the liquid crystal can be modified. Confinement conditions can be obtained by dispersing the liquid crystal in a polymer matrix or in porous glasses. (AU)