SYNTHESIS AND PROPERTIES OF AROMATIC POLYOXADIAZOLES AND POLYAZOMETHINES CONTAINING TRIPHENYLAMINE MOIETIES

• Main Authors: Juan-Quan Ruan, 阮俊銓
• Other Authors: Sheng-Huei Hsiao
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/58095654130611798005

碩士 === 大同大學 === 化學工程研究所 === 91 === ABSTRACT Two triphenylamine-containing monomers, N,N’-bis(4-carboxyphenyl)-N,N’-diphenyl-1,4-phenylenediamine (3) and N,N’-bis(4-aminophenyl)-N,N’-diphenyl-1,4-phenylenediamine (5) were synthesized by the aromatic nucleophilic displacement of N,N’-diphenyl-1,4-phenylenediamine with p-fluorobenzonitrile or p-fluoronitrobenzene, respectively, followed by alkaline hydrolysis or hydrazine catalytic reduction of the intermediates dinitrile or dinitro compounds. Two novel poly(amine-hydrazide)s 6 and 7 and one poly(amine-amide-hydrazide) 8 were prepared from the triphenylamine-based dicarboxylic acid 3 with terephthalic dihydrazide (TPH), isophthalic dihydrazide (IPH), and p-aminobenzoyl hydrazide (p-ABH), respectively, via the Yamazaki phosphorylation reaction. Polymers 7 and 8 were readily soluble in various polar organic solvents such as N-methyl-2-pyrrolidone (NMP) and N-N-dimethylacetamide (DMAc), and could be solution-cast into free-supporting films. Differential scanning calorimetry (DSC) indicated that these hydrazide polymers had Tg’s in the range of 193—218 oC and could be thermally cyclodehydrated into the corresponding oxadiazole polymers at elevated temperatures. The resulting poly(amine-1,3,4-oxadiazole)s 9 and 10 and poly(amine-amide-1,3,4,-oxadiazole) 11 exhibited Tg’s in the range of 234—257 oC, 10 % weight-loss temperatures in excess of 485 oC, and char yield at 800 °C in nitrogen higher than 59%. The photoluminescent peaks of polymers 9, 10, and 11 in thin films were at about 685, 690, and 698 nm, respectively, which corresponded to the emission of blue-green, green, and green light. Furthermore, two new triphenylamine-based aromatic polyazomethines 12 and 13 were synthesized by high-temperature solution polycondensation of the triphenylamine-based diamine 5 with isophthalaldehyde and terephthalaldehyde in NMP/toluene. The aromatic polyazomethines 12 and 13 had inherent viscosities of 0.16 and 0.28 dL/g, respectively. They were soluble in NMP and m-cresol. These azomethine polymers showed high thermal and thermo-oxidative stability; they exhibited no appreciable decomposition before 400 ℃ in nitrogen or air and left char yields at 800 ℃ in nitrogen higher than 50%. Their glass transition temperatures (Tg) ranged from 191 to 230 ℃. UV-visible and fluorescence spectrometers were employed to investigate their optical properties both in solution and in solid film. Photoluminescence maxima of polymers 12 and 13 in NMP solutions were 464 and 480 nm, respectively, and in film state were 684 and 698 nm, respectively.