Abstract: | Novel poly(amide-imide-imide)s (PAII) were prepared by polycondensation of a new monomer synthesized from trimellitic anhydride and glutamic acid, followed by reflux condensing with thionyl chloride and several diamines. Polymers and monomers were characterized by 1H NMR and FT-IR spectroscopy, elemental analysis and mass spectrometry. Inherent viscosities of the resulting polymers were in the range of 17–26 mL g–1 (Mw 13 400–29 160, polydispersity (Mw/Mn) ca. 1.3–1.7), representing rather low molecular weights. The glass transition temperatures of the polymers were in the range of 210–285°C depending on the structure of diamines, and the thermal stability of the polymers was up to 400°C, comparable with that of polyimides and poly(amide imide)s. All the polymers synthesized are well soluble in aprotic polar solvents such as dimethylformamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone and dimethylacetamide. Particularly, polymers containing oxydianiline and 4,4′-diaminodiphenyl sulfone were quite soluble in m-cresol, pyridine, nitrobenzene and tetrahydrofuran. |