EFFECTS OF POLYMERIZATION ON CHROMOPHORE STACKING IN BILAYER-MEMBRANES

Two novel polymerizable double-chained ammonium amphiphiles carrying m esogenic cyanobiphenylyloxy units have been synthesized containing met hacrylate in the headgroup or diacetylene groups in the hydrophobic ta ils. These compounds form bilayer vesicles upon dispersion in water. P olymerization increases the vesicle stability toward solubilization by a nonionic surfactant. The stacking of the cyanobiphenylyloxy units i n the bilayer is directly monitored by the extent of the blue shift of the absorption maximum. Upon polymerization a decrease in blue shift is observed, reflecting a decrease in the ordering of the amphiphile m olecules. This effect is stronger when polymerization occurs in the hy drophobic tails than in the headgroup region.