Helical twisting power of three-ring chiral molecules and polymerization in cholesteric electrolyte solutions

A series of chiral three-ring type compounds with rigid shape was employed as chiral inducers for induction of chiral cholesteric liquid crystal (cholesteric LC) from achiral nematic LC. Helical twisting power of the chiral compounds was estimated with the Cano wedge method. Cholesteric LC electrolyte solution was prepared by adding the chiral compounds. Subsequently, polymerization in the cholesteric LC was carried out to produce chiroptically active polymer films. This method is different from conventional methods for synthesizing chiral polymers because neither chiral monomers nor asymmetric catalysts are employed. Surface structure and optical properties of the polymer thus prepared were examined.