The synthesis and structural characterization of a series of novel, fluorinated poly(phthalazinone ether)s containing perfluorophenylene moieties are described. The monomers, 4-(4'-hydroxyaryl)phthalazin-1(2H)-ones (2a-2d), were conveniently and efficiently synthesized from phenols and phthalic anhydride in two steps via 2-(4'-hydroxybenzoyl)benzoic acids, which were first obtained by the Friedel-Crafts reaction in good yields and with high stereoselectivity and were then converted into 2a-2d by fusion with hydrazine. All the polymers were prepared by nucleophilic aromatic substitution (SNAr) polycondensation between the compounds perfluorobiphenyl and 4-(4'-hydroxyaryl)phthalazin-1(2H)-ones (2a-2d). The resulting fluorinated polymers were readily soluble in common organic solvents (e.g., CHCl3, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, etc.) at room temperature. Their weight-average molecular weights and the polydispersities ranged from (7.96-18.25) X 10(3) to 1.31-2.71, respectively. Their glass-transition temperatures varied from 213 to 263 degreesC. They were all stable up to 390 degreesC both in air and in argon. The 5% weight-loss temperatures of these polymers in air and argon ranged from 393-487 to 437-509 degreesC, respectively. Wide-angle X-ray diffraction studies indicated they were all amorphous and could be attributed to the presence of kink nonplanar moiety, phenyl phthalazinone along the polymer backbone. (C) 2004 Wiley Periodicals, Inc.