Containing Two-dimensional Mesogenic Units And Crown Ether Cycle Synthesis And Characterization Of Liquid Crystalline Copolyester

The dissertation consists of six parts.1 The progress made in this field and the idea of our workThe concepts of liquid crystal, crown ether, liquid crystal crown ether, liquid crystalline polymers and liquid crystalline polymers containing two-dimensional mesogenic units were introduced. The progress made in this field and the assumption of our work were also introduced.2 Synthesis and characterization of main-chain liquid crystalline copolyesters with X-shaped phenyl two-dimensional mesogenic units andcis(trans)-4,4 ' -bis (4-hydroxyphenylazo)dibenzo-18-crown-6A novel kind of main chain liquid crystalline copolyesters with X-shaped two-dimensional mesogenic unit and crown ether cycle were prepared via solution condensation polymerization using 4,4 ' -(α,ω-hexanedioyloxy) dibenzoyl dichloride, 2,5-bis(p-alkoxybenzoyloxy)hydroquinone and cis(trans)-4, 4 ' -bis(4-hydroxyphenyl-azo)diben-zo-18-crown-6. The copolyesters can be divided into two series according to their molecule structures. The structures are shown as follows:...