【摘 要】
：
A novel type of aromatic poly ( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl) pentanoic acid with dif
【机 构】
：
School of Materials Science and Engineering,Alan G. MacDiarmid Institute
【基金项目】
：
Open Project of State Key Laboratory of Supramolecular Structure and Materials;国家自然科学基金
论文部分内容阅读
A novel type of aromatic poly ( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl) pentanoic acid with difluoro-monomers.Their molecular structures were determined by 1 H-NMR and IR,respectively.Their molecular weights were measured by gel permeation chromatography ( GPC ),which showed that all the polymers had high molecule weights ( ＞ 42 000 ).Due to the long side chains of polymers,all the polymers had good solubility (soluble in NMP,DMAc,THF,etc.).The differential scanning calorimeter (DSC) detected their excellent glass transition temperatures ( Tg ) up to 195 ℃.The Tg increased with the content of carboxylic units in the polymer chains,because the interactions of H bonds increased with increasing content of carboxylic.The polymers could form transparent and flexible films,which make them a candidate for membrane materials.
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