Highly fluorinated, hyperbranched polymers were synthesized from the polycondensation of AB(2) monomers, 3,5-bis[(pentafluorobenzyl)oxy]benzyl alcohol and 3,5-bis[(pentafluorobenzyl)-oxy]phenol with potassium carbonate base, and 18-crown-6 phase transfer agent in a variety of polar aprotic solvents. The regioselectivity of the polymerization was optimized and was found to be temperature dependent. The new polymerization technique produced higher molecular weight polymer using safer conditions than earlier methods. The resulting optimization was used to control substitution of oxygen-bearing nucleophiles along nonactivated fluoroaryl systems in high yield. Water was found to induce side reactions that generate a highly conjugated fluoroaryl phenol with lowered reactivity. The removal of a methylene spacer in the polymer backbone of the hyperbranched polymer produced a polymer with greater thermal stability. The reaction conditions for polymerization were found to be general for nucleophile-bearing perfluorinated systems. (c) 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 985-994