Liquid-crystalline comb-shaped oligoacrylates and oligomethacrylates with 4-cyanoazobenzene mesogenic groups

Two homologous series of acrylic and methacrylic monomers with 4-cyanoazobenzene mesogenic groups were synthesized. Members of each series contained a different number of carbon atoms (from two to eleven) in the aliphatic chain of the spacers between the mesogenic groups. LC oligomers with the degree of polymerization ranging from 10 to 100 were prepared from these monomers by radical polymerization. Properties of the LC phases of the oligomers were investigated, and regularities that control the formation of mesophases as the length of spacer is varied were studied for chemically different main chains. A model that describes the arrangement of the macromolecules of acrylic and methacrylic oligomers in the LC phase was suggested.