| Summary: | 博士 === 大同大學 === 化學工程研究所 === 90 === Synthesis and properties of organosoluble polyimides based on pendant group-containing diamines and light-colored poly(amide-imide)s on the basis of commercial monomers were investigated in this dissertation.
Three diamine monomers, 2,5-bis(4-aminophenoxy)biphenyl, 1,2-bis(4-aminophenoxy)-4-tert-butylbenzene, and 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenylethane, were prepared through a nucleophilic substitution reaction of corresponding bisphenols and p-halonitrobenzene in the presence of potassium carbonate in N,N-dimethylformamide, followed by catalytic reduction with hydrazine and Pd/C in ethanol. Novel organosoluble polyimides bearing pendent groups were synthesized from these diamines with six kinds of commercial dianhydrides. For improving solubility, copolyimides with arbitrary solubilities were prepared from diamines and a pair of dianhydrides, which were mixed at certain molar ratios. These copolymers could improve the processability of polymers, while maintaining or increasing their excellent mechanical properties and heat-resistant properties.
Three series of light-colored poly(amide-imide)s were also prepared systematically. Three imide-containing dicarboxylic acids were prepared by azeotropic condensation of diamine with terminal meta-structure and trimellitic anhydride at a 1:2 molar ratio, dianhydride and m-aminobenzoic acid at a 1:2 molar ratio, or diamine, dianhydride, and m-aminobenzoic acid at a 1:2:2 molar ratio in polar solvent and toluene. Poly(amide-imide)s were synthesized from these diacids and various aromatic diamines by the direct polycondensation using triphenyl phosphite and pyridine as condensing agents. From UV-visible spectrum and resulting parameters of Macbeth Color-eye colorimeter, these poly(amide-imide)s were much lighter in color than other analogous polymers. Polymers afforded tough, transparent, and flexible films that were characterized by good mechanical properties together with excellent thermal stability.
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