Synthesis and Properties of Thermotropic Poly(Ester-Amide)S Having Semiregular Monomer Sequences

Dichloride of 4,4′-(carbonylimino)dibenzoic acid was polymerized in 1,1,2,2-tetrachloroethane with a series of monosubstituted hydroquinone (series I) or α, ω-bis(4-hydroxyphenoxy)alkanes (series II) having alkane units of varying length. the polymers obtained were characterized by IR and NMR spectroscopy, solution viscosity measurements, and differential scanning calorimetry (DSC). Formation of mesophase and thermal behavior also were studied on a hot-stage attached to a polarizing microscope. All of the polymers were thermotropic and the transition temperatures were highly dependent on the nature of substituents on hydroquinone in the first series and on the length of alkylene spacers in the second series.