Preparation and characterization of aromatic polyamides based on a bis(ether-carboxylic acid) or a dietheramine extended from 1,1-bis(4-hydroxyphenyl)-1-phenylethane

Thermoplastic and organic-soluble aromatic polyamides containing both bulky triphenylethane units and flexible ether linkages were prepared directly from 1,1-bis [4-(4-carboxyphenoxy)phenyl]-1-phenylethane (III) with various aromatic diamines or from 1,1-bis [4-(4-aminophenoxy)phenyl]-1-phenylethan (V) with various aromatic dicarboxylic diacids via triphenyl phosphite and pyridine. These polyamides had inherent viscosities ranging from 0.71 to 1.77 dL/g. All the polymers easily were dissolved in aprotic polar solvents such as N-methyl-2-pyrrolidone and N,N-dimethylacetamide, and some even could be dissolved in less polar solvents such as tetrahydrofuran. The flexible and tough films cast from the polymer solutions possessed tensile strengths of 89 to 104 MPa. The polyamides were thermally stable up to 460 degrees C in air or nitrogen. Glass-transition temperatures of these polyamides were observed in a range of 179 to 268 degrees C via differential scanning calorimetry or thermomechanical analysis. (C) 2000 John Wiley & Sons, Inc.