| Summary: | 碩士 === 國立臺灣科技大學 === 化學工程系 === 90 === A novel bis(ether anhydride) monomer, 9,9-bis[(4-(3,4-
dicarboxyphenoxy)-3-phenyl)phenyl]fluorene dianhydride(3), was synthesized from the nitrodisplacement of 4-nitrophthalonitrile by the bisphenoxide ion of 9,9-bis[(4-
hydroxy-3-phenyl)phenyl]fluorene, followed by alkaline hydrolysis of the intermediate tetranitrile and dehydration of the resulting tetracarboxylic acid. A series of poly(ether imide)s bearing the fluorenylidene group and the phenyl side groups were successfully synthesized from the bis(ether anhydride) 3 with various aromatic diamines via the one-step method that included ring-opening polyaddition to form the poly(amic acid)s followed by chemical imidization to the polyimides 5. The polyimides with inherent viscosities ranging from 0.42 to 0.63 dL/g showed excellent solubilities in common solvents such as 1-methyl-2-pyrrolidinone(NMP), N,N-dimethylacetamide, chloroform, tetrahydrofuran, and cyclohexanone. This kind of fluorene-based polyimide can form a tough and transparent film. The films have tensile strengths of 50~111 MPa, and elongation to break of 2~6%. Differential scanning calorimetry(DSC) and dynamic mechanical analysis(DMA) reveal their glass transition temperatures were found to be 249~268℃ and 270~295℃,respectively. Thermogravimetric analyses demonstrated that almost all polymers were stable up to 450℃, and the 10% mass loss temperatures were recorded in the range of 488~554℃ in nitrogen atmosphere.
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