New poly(amide imide imide)s based on tetraimide dicarboxylic acid condensed from 4,4?-(hexafluoroisopropylidene)diphthalic anhydride,m-aminobenzoic acid, and 4,4?-oxydianiline and various aromatic diamines

Abstract

A series of new, organosoluble, and light-colored poly(amide imide imide)s were synthesized from tetraimide dicarboxylic acid (I) and various aromatic diamines by direct polycondensation with triphenyl phosphite and pyridine as condensing agents. I was prepared by the azeotropic condensation of 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, m-aminobenzoic acid, and 4,4′-oxydianiline at a 2/2/1 molar ratio in N-methyl-2-pyrrolidone (NMP)/toluene. The thin films cast from N,N-dimethylacetamide (DMAc) had cutoff wavelengths shorter than 400 nm (365–394 nm) and color coordinate b* values between 13.10 and 36.07; these polymers were lighter in color than the analogous poly(amide imide)s and isomeric polymers. All of the polymers were readily soluble in a variety of organic solvents, including NMP, DMAc, N,N-dimethylformamide, dimethyl sulfoxide, and even less polar dioxane and tetrahydrofuran. The cast films exhibited tensile strengths of 90–104 MPa, elongations at break of 7–22%, and initial moduli of 1.9–2.4 GPa. The glass-transition temperatures of the polymers were recorded at 274–319°C. They had 10% weight losses at temperatures beyond 520°C and left more than a 50% residue even at 800°C in nitrogen. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 669–679, 2003