Synthesized and mesomorphic properties of cholesterol end-capped poly(ε-caprolactone) polymers

Cholesterol end-capped linear and star-shaped poly(epsilon-caprolactone) (PCL) polymers were prepared by a combination of copper catalyzed azide-alkyne cycloaddition (CUAAC, click chemistry) and ring-opening polymerization (ROP) techniques. The chemical structures of these polymers were determinated by Fourier Transform Infrared (FTIR), H-1 NMR, P-31 NMR, and Gel Permeation Chromatography (GPC). Mesogenic properties of these polymers were examined by wide and small-angle X-ray scattering (WAXS and SAXS), differential scanning calorimetry (DSC) and polarising optical microscopy (POM). The results revealed that PCLs have focal conic textures of the smectic liquid crystals, encouraging the mesomorphism. The mesomorphic temperature ranges became widen with the increasing amount of cholesterol moiety in the polymers.