Liquid crystals derived from hydrogen-bonded supramolecular complexes of pyridinylated hyperbranched polyglycerol and cholesterol-based carboxylic acids

A hyperbranched polyether polyol was reacted with isonicotinoyl chloride hydrochloride for the introduction of the pyridinyl moiety at the external surface. This pyridinylated hyperbranched polymer was subsequently interacted with cholesterol-based carboxylic acids for the formation of the corresponding hydrogen-bonded supramolecular complexes. The materials obtained exhibited smectic A liquid crystalline phases over a broad thermal range from room temperature up to above 170degreesC. Within this smectic layer the cholesterol moieties are located above and below the hyperbranched scaffold. Increasing the spacer length, located between the carboxylic group and the cholesterol moiety, the temperature range of the liquid crystalline phases of the complexes is lowered.