Structural and Thermomechanical Investigation of Lyotropic Liquid Crystal Phases Doped with Monodisperse Microparticles
نویسنده
چکیده
We present a study of the structural and thermomechanical properties of lyotropic phase in the quasi ternary system made of Cetylpyridinium chloride (CPCl)/hexanol/salt water (0.9 % by mass) with and without cobalt microparticles. Phase transition temperatures of the structural sequence isotropic L 1/nematic calamitic Nc ,/hexagonal H have been determined by differential scanning microcalorimetry. Temperature induced developable domains in hexagonal phase H and disclinations in calamitic nematic phase Nc were observed in crossed polar optical microscopy in confined geometry. A rheological study of calamitic nematic phase Nc highlighted structuring effect of cobalt microparticles from a concentration of 2 % to be demonstrated by an increase in viscosity and viscoelastic moduli. This could be explained by a stabilization of disclinations.
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