作者: Corneliu Hamciuc , Mihaela Homocianu , Elena Hamciuc , Ionela-Daniela Carja
DOI: 10.1016/J.REACTFUNCTPOLYM.2016.03.022
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摘要: Abstract New poly(1,3,4-oxadiazole-imide)s were synthesized from a diamine containing 1,3,4-oxadiazole ring, 4,4′-diamino-4″-[(2-(4-phenoxy)-5-(4-dimethylaminophenyl)-1,3,4-oxadiazole]triphenylmethane, and different aromatic dianhydrides: 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, 9,9-bis[(3,4-dicarboxyphenoxy)phenyl]fluorene dianhydride, 4,4′-(4,4′-isopropylidenediphenoxy)bis(phthalic anhydride) perylene-3,4,9,10-tetracarboxylic dianhydride. The polymers easily soluble in polar organic solvents exhibited high thermal stability, having 5% weight loss the range of 445–470 °C glass transition temperature domain 201–244 °C. optical properties investigated media. absorption characteristics (intensity, maximum shape) compounds depended on their chemical structures nature environment. emission these samples was represented by one broadened blue band. largest solvent dependent Stokes shifts values obtained. fluorescence quantum yield (QY) polymer with hexafluoroisopropylidene groups, tetrahydrofuran solution, wavelength used for excitation. This is an exception Kasha's rule Vavilov's law, which attributed either to photodecomposition or enhancement intramolecular energy transfer process competing internal conversion between singlet states. High QY obtained isopropylidene fluorene units dimethyl sulfoxide (polar solvent), may be due strong overlap electronic transitions species system.