Abstract
New fluorinated poly(1,3,4-oxadiazole-ether)s were prepared by nucleophilic aromatic substitution technique of an activated aromatic difluorinated compound with a bisphenol containing three trifluoromethyl groups, namely 1, 1-bis(4'-hydroxyphenyl)-1-(3', 5'-ditrifluoromethylphenyl)-2, 2,2-trifluoroethane, 1, or with a mixture of 1 and 9,9-bis(4-hydroxyphenyl) fluorene. FTIR and NMR spectroscopy were used to confirm the structure of the polymers. The polymers were easily soluble in organic solvents and could be processed in flexible thin films. The film surfaces exhibited hydrophobic characteristics, as it was determined by contact angle measurements. The polymers had high thermal stability, up to 440 degrees C, and glass transition temperature in the range of 202-237 degrees C. They showed fluorescence in the blue region, both in solution and in solid state. The change in electronic absorption and emission spectra of one of the polymer in neat and binary solvent mixtures has been studied. Broadband dielectric spectroscopy was used to investigate the relaxation processes in polymers. The dielectric constant of the polymers was in the range of 2.84-2.96, at 100 degrees C and 10 kHz, and decreased with the increase of fluorine content.