J. Kotz et S. Kosmella, POLYMERS IN LYOTROPIC LIQUID-CRYSTALLINE SYSTEMS, Colloids and surfaces. A, Physicochemical and engineering aspects, 123, 1997, pp. 265-276
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.