Main-chain chiral smectic liquid-crystalline ionomers containing sulfonic acid groups

摘要

Three series of main-chain liquid-crystalline polymers (P1, P2, and P3) were synthesized by an interfacial condensation reaction of sebacoyl dichloride with various amount of brilliant yellow, isosorbide, and 4,4'-biphenydiol. P1 series are polyesters prepared from sebacoyl chloride and various amount of 4,4'-biphenyldiol and isosorbide. P2 series are polyesters prepared from sebacoyl chloride and various amount of 4,4'-biphenyldiol, brilliant yellow, and isosorbide. P3 series are polyesters prepared from sebacoyl chloride and various amount of 4,4'-biphenyldiol and brilliant yellow. P2 and P3 are main-chain liquid-crystalline ionomers. P1(2) and P3 series were prepared as model polymers for comparison with the liquid crystalline behavior of ionomers, P2 series. The structures of the polymers were characterized by IR and UV spectroscopy. Differential scanning calorimetry was used to measure the thermal properties of the polymers. The mesogenic properties were investigated by polarized optical microscope, differential scanning calorimetry, and X-ray diffraction measurements. The results show that P2 series are chiral smectic C (SmC*) and chiral smectic B (SmB*) liquid crystalline ionomers exhibiting broken focal-conic texture and schlieren, as is the polymer P1(2), which has the same amount of 4,4'-biphenydiol and isosorbide. The introduction of ionic units in P2 series leads to an increase of clearing point, but has not affected the mesogenic type and texture, as compared with the corresponding polymer P1(2). The introduction of chiral units in P2 series leads to a change of mesophase, as compared with P3 series, which exhibit smectic C mesogetic phase. (c) 2005 Wiley Periodicals, Inc.