POLYMERS IN LYOTROPIC LIQUID-CRYSTALLINE SYSTEMS

The influence of oppositely charged polyelectrolytes and copolymers of different charge density and polyanion-polycation mixtures on the pre ordered lamellar liquid crystalline system sodium dodecylsulfate-decan ol-water due to Coulombic interactions with special accentuation of ag gregation and adsorption phenomena was examined. Small-angle X-ray res ults and rheological investigations are discussed with regard to chang es in the interlayer spacing after introducing the polymers at various concentrations. The liquid crystalline phase was maintained, but the preformed lamellar structure was modified via penetration of the macro molecules between the hydrocarbon chains of the surfactant molecules. In the case of the polycation, strong Coulombic interactions cause a s o-called ''frozen'' structure, whereas for the copolymers with decreas ing charge density a ''loop'' conformation becomes possible, resulting in significantly increased interlayer spacings. Polyanions and polyan ion-polycation mixtures showed phenomena of phase separation.