Branched-arm macromolecule liquid crystals-containing fluorine and isosorbide-structure and properties

• Four precursor of nematic liquid crystalline branched-arm and four chiral liquid crystalline branched-arm LC were synthesized.
• The structures of the prepared compounds have been investigated by different spectroscopic techniques.
• The thermal behavior, optical texture property and optical activity have been evaluated.

A new series of cholesteric fluorated branched-arm liquid crystals (CHFBALCs) compound (MFA1–MFA4), with isosorbide as chiral core, was synthesized. Four precursors of branched-arm FA1–FA4 were obtained firstly and then were esterized separately with isosorbide to get four chiral branched-arm liquid crystalline (MFA1–MFA4). The structures and properties were characterized by conventional spectrum methods, thermal analysis and texture analysis. The results showed that FA1–FA4 all were nematic phase with schlieren, threaded-like or droplet texture. When the isosorbide was successfully inducted, the phase of FA1–FA4 turned into cholesteric phase with oily streak texture, finger print texture or cholesteric droplets. The values of melting point and clearing point for FA1–FA4 and MFA1–MFA4 all changed irregularly, which may be due to the effect of different branched arm, warping of chiral agent and fluorine atom. MFA1–MFA4 had the same handedness as isosorbide core and did not show selective reflection. MFA3 and MFA4 were hopeful to realize the combination of the processability of polymers and the mobility of small molecules.