Comparative investigations of phase states, mesomorphic and morphologic properties in hexadecyltrimethyl ammonium bromide/water and hexadecyltrimethyl ammonium bromide/water/1-decanol lyotropic liquid crystalline systems

Morphologic Properties, Texture Transformations and Optical Refracting Properties: Aqueous Bicomponent Amphiphilic Lyotropic Systems

The mesomorphic, morphologic and optical refracting properties of the bicomponent amphiphilic lyotropic systems have been investigated. Five amphiphiles with various concentration combinations as cationic – cationic, anionic – anionic and cationic – anionic lyotropic mixtures have been used for preparation of lyotropic systems. The mixtures were prepared with a constant (amphiphile1 + amphiphile2)/water concentration ratio. Isotropic lyotropic phase and hexagonal and lamellar lyotropic mesophases have been found in lyotropic systems under investigations. Dynamics of change of the magneto-morphologic properties vs. time, character of the heterophase regions of the mesophase – isotropic liquid phase transitions and temperature dependencies of the optical refracting properties of these bicomponent amphiphilic lyotropic systems have been investigated.

Investigation of Phase States, Thermo-Morphologic, Magneto-Morphologic and Refractive Properties of Mesophases in Dodecyltrimethyl Ammonium Bromide – Water Lyotropic Liquid Crystalline System

We report the phase states in dodecyltrimethyl ammonium bromide/water (DDTMABr–H2O) lyotropic liquid crystalline system. The temperature-concentration phase diagram of this system has been determined. Isotropic micellar L1 phase, nematic-calamitic NC and hexagonal E mesophases have been observed in DDTMABr/H2O system. Dynamics of transformations of magnetically induced textures in NC and E mesophases has been investigated. Temperature and concentration dependences of the refractive index in the L1 phase, NC and E mesophases have been determined. The appearance of the magnetically induced aligned textures of NC mesophase and changes of the optical birefringence vs. time have been investigated.

Amphiphile/Water/Decanol Lyotropic Liquid Crystalline System: Study of Thermal States of Anisometric Micelles in Nematic-Calamitic and Nematic-Discotic Mesophases

Structural peculiarities of the rod-like micelles in the nematic-calamitic (NC) and disc-like micelles in the nematic-discotic (ND) lyotropic mesophases have been investigated. Hexadecyltrimethyl ammonium bromide/water/1-decanol ternary lyotropic system was used. Temperature changes of the shapes and anisometricity of the rod-like and disc-like micelles have been estimated. The method of the electrical conductivity anisotropy in the orientational shear flow has been used for these estimations. Sign of the diamagnetic anisotropy of the NC and ND mesophases has been also determined. The rod-like micelles of the NC mesophase were considered as the prolate ellipsoids and the disc-like micelles of the ND mesophase were considered as the oblate ellipsoids.