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Study on the Functionalization of Hyperbranched Poly (Aryl Ether Ketone)

Author: WangDong
Tutor: JiangZhenHua
School: Jilin University
Course: Polymer Chemistry and Physics
Keywords: Hyperbranched poly (aryl ether ketone) azobenzene metallophthalocyanine sulfonic acid group
CLC: O631.3
Type: PhD thesis
Year: 2008
Downloads: 235
Quote: 1
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Abstract

Recently the well-defined structures of dendrimers have attracted much attention due to their novel properties. However, the stepwise divergent or convergent synthetic methods for dendrimers have limited their usage. The hyperbranched polymers can be constructed by a direct one-pot polymerization that raises the new interest in polymer science. It is well known that linear poly(aryl ether ketone)s possess high Tg, excellent thermal stability and good mechanical properties, therefore they usually act as the backbone of linear polymers containing functional groups.Our current effort focus on discussing the influence of hyperbranched structure on the properties of functional materials, therefore the hyperbranched poly(aryl ether ketone) containing azo group, metallophthalocyanine group and sulfonic group were prepared.1. Preparation of azo-terminated hyperbranched poly(aryl ether ketone)s: we first synthesized 1, 3, 5-tris [4-(4- fluorobenzoyl) phenoxy] benzene (B3 monomer). The fluoro-terminated hyperbranched poly(aryl ether ketone)s were prepared by using B3 monomer as a core molecule, 4,4′-(hexafluoroisopropylidene) diphenol as a A2 monomer. The hyperbranched polymers could be end-capped with azo groups from the fluoro-terminated polymer. With increasing the content of azo groups, the Tg of polymers increase due to the polarity of end group, the T5% of polymers decrease due to the decomposition of azo group prior to the backbone of poly (aryl ether ketone) and the thermal isomerization rate of polymers slightly decrease due to the increase of the interaction among the azo groups.2. Preparation of metallophthalocyanine-terminated hyperbranched poly(aryl ether ketone)s: the hydroxyl-terminated hyperbranched poly(aryl ether ketone)s was prepared by using B3 monomer as a core molecule, 4,4′-(hexafluoroisopropylidene) diphenol as a A2 monomer. The hyperbranched polymers could be end-capped with metallophthalocyanine from the hydroxyl-terminated polymer. The result suggested that the third order nonlinear optical susceptibilityχ(3) of the nickelphthalocyanine-terminated hyperbranched poly(aryl ether ketone) solution was as large as≈10-11 esu at 532 nm. In addition, under the oxidant KHSO5 condition, we discussed the catalyzed degeneration trichlorophenol (TCP) performance of cobalt phthalocyanine-terminated hyperbranched poly(aryl ether ketone) in comparison with cobalt phthalocyanine-terminated linear poly(aryl ether ketone). The result suggests the catalytic efficiency of cobalt phthalocyanine-terminated hyperbranched poly(aryl ether ketone) is better than that of cobalt phthalocyanine-terminated linear poly(aryl ether ketone). The phenomena may origin from the highly branched structure and enough end groups of metallophthalocyanine. 3. Preparation of hyperbranched poly(aryl ether ketone)s containing sulfonic groups: the fluoro-terminated hyperbranched poly(aryl ether ketone) was prepared by using B3 monomer, as a core molecule, 4,4′-dihydroxyl-diphenylether as a A2 monomer. The hyperbranched polymers containing sulfonic groups could be obtained from the fluoro-terminated hyperbranched poly(aryl ether ketone)s by post-sulfonation. In order to investigate the influence of the addition of sulfonated hyperbranched poly(aryl ether ketone) on the proton conductivity of sulfonated linear poly(aryl ether ketone), the sulfonated hyperbranched poly(aryl ether ketone) of different sulfonate degree were mixed with the sulfonated linear poly(aryl ether ketone). The result shows that the introduction of hyperbranched poly(aryl ether ketone) containing sufonic groups will interrupt the close pack of the linear poly(aryl ether ketone)s containing sulfonic acid and increase the free space between them, which will favor the water retention and increase the connection of the inonic domains in the linear poly(aryl ether ketone)s containing sulfonic acid.

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