Dichroic dyes, and liquid crystalline side chain polymers


  • The author is grateful to Dr. H. Eilingsfeld, Dr. K.-H. Etzhach, Dr. G. Wagenblast (BASF AG, Ludwigshafen) and to Dr. G. Baur, and Dr. R. Kiefer (Fraunhofer-Institut für Angewandte Festkörperphysik, Freiburg) for fruitful collaboration and to Prof. H. Ringsdorf (University of Mainz) for his continuous support


Functional guest molecules incorporated into LC-side-chain polymers lead to polymeric materials which combine the physical and optical anisotropic properties of liquid crystals with the special functions of the guest components. This contribution focused on dichroic dyes, but the results are transferable to other guest moieties. The covalent fixation of the dye to the polymer backbone affords several advantages. Liquid crystalline materials with high dye concentrations were obtained opening the way to the preparation of highly ordered, optical uniaxial films with adjustable thickness and optical density. Thin well aligned LC-polymer films can in principle be used as an active medium for reversible optical information storage and mixtures of dye-containing copolymers in low molar mass liquid crystals can be used in displays. Current developments in the area of ferroelectric chiral smectic-C side-chain polymers will further enhance interest in this area.