Langmuir monolayers of mesomorphic monomers and polymers

Abstract

Monolayers of organic compounds which exhibit liquid crystalline behaviour in their bulk phases have been formed at an air-water interface. All selected polymers and monomers were of the same basic structure with a rigid aromatic central core containing several hydrophilic ester groups and two or more aliphatic hydrocarbon chains. Spreading was satisfactory in most cases and the surface pressure was found to increase monotonously with surface concentration. At the highest pressure attainable the minimum surface area per molecule corresponds to a vertical orientation, with some of the anchoring ester groups lifted up from the water subphase. In the lower pressure region, there is some evidence that the molecules lie flat on the interface