Liquid crystalline polymers containing sodium sulfonate groups pendant to the polymer backbone were synthesized by an interfacial condensation reaction of brilliant yellow, a sulfonate-containing monomer, with 4,4'-dihydroxy-a,a'-dimethyl benzalazine and a 50/50 mixture of sebacoyl and dodecanedioyl dichlorides. Polymers containing up to ca. 4mol% brilliant yellow were characterized by elemental analysis and ultraviolet spectroscopy. The polymers were thermally stable to about 300℃, and they exhibited a broad nematic mesophase region of 70-100℃. The solution viscosity behavior in chloroform suggested that intramolecular associations of the sulfonate groups occurred at low polymer concentrations and internolecular associations predominated at higher concentrations.