POLY(AMIDE-IMIDE)S PREPARED FROM 4,4'-[1,4(OR ENEBIS(ISOPROPYLIDENE-1,4-PHENYLENEOXY)]DIANILINE, TRIMELLITIC ANHYDRIDE, AND VARIOUS AROMATIC DIAMINES

Two imide ring-bearing dicarboxylic acids, N,N'-[1,4(or 1,3)-phenylene bis(isopropylidene-1 ,4-phenyleneoxy-1,4-phenylene)] diphthalimide-4-c arboxylic acid (p-4 and m-4), were prepared via condensation of 4,4'-[ 1,4(or 1,3)-phenylenebis(isopropylidene-1, 4-phenyleneoxy)]dianiline ( p-3 and m-3) with trimellitic anhydride. Two series of novel poly(amid eimide)s were synthesized by the direct polycondensation of the diimid e-diacids p-4 and m-4, respectively, with various aromatic diamines us ing triphenyl phosphite and pyridine as condensing agents. The inheren t viscosities of the resultant poly(amide-imide)s were in the range of 0,43 - 1,68 dL/g, and most of these polymers were amorphous, as revea led by wide-angle X-ray diffractograms. Almost all the poly(amide-imid e)s were readily soluble in polar aprotic solvents such as N-methyl-2- pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), and N,N-dimethylforma mide (DMF), and could be solution-cast into transparent, flexible, and tough films. These polymers had glass transition temperatures in the range of 200 - 267 degrees C and showed no significant decomposition b elow 450 degrees C, with 10% weight loss being recorded above 485 degr ees C in nitrogen or air.