Syntheses and characterization of Chiral Branched-Arm Liquid Crystals-Basing on Isosorbide as Chiral Core

摘要

A new scries of two-arm (MB1, MB2), four-arm(MB3), six-arm(MB4) chiral liquid crystalline compound containing isosorbide as chiral core were first synthesized. Four precursors of bunched-arm B1 - B4 were obtained at first and then were esterized separately with isosorbide and got four chiral branchcd-arm liquid crystals (MB1-MB4). The chemical structures and LC properties of the liquid crystalline molecule were measured by spectrum and thermal analysis techniques. XRD curves of MB I ~MB4 samples only showed broad peaks at wide-angle, but no sharp peak was seen for all the samples. The results showed that MB1-MB4 appeared cholesteric phase with oily streak texture or lined texture and finger print texture. Isosorbide successfully induced cholesteric phase, The values of melting point and clearing point for MB1-MB4 decreased. The quantity of branched-arm and chiral core had effects on their liquid crystalline properties.