Novel fluorinated polymer synthesis with anionic polyaddition by double Michael addition reaction of 2-trifluoromethylacrylate derivatives with ethyl cyanoacetate (ECA) was proposed. Diaddition product of ECA with phenyl 2-trifluoromethylacrylate was yielded in high yield by the catalysis of sodium ethoxide in tetrahydrofuran at 60 degrees C. Sodium hydroxide catalyzed double Michael addition reaction also produced diaddition product in high yield. Novel anionic polyaddition of 1,4-phenylene bis(2-trifluoromethylacrylate) [CH2=C(CF3)COOC6H4OCOC(CF3)=CH2] (PBFA) with ECA afforded the polymer of 1.2 x 10(4) as the highest molecular weight. The isolated polymer gave the polymer of 2.8 x 10(4) as a molecular weight by the reaction of the isolated polymer with PBFA in the presence of sodium etboxide; which proved that the polymer end groups were mainly ECA moieties. The reaction mechanism that the proton abstraction from ECA followed by the addition of 2-trifluoromethylacrylate was proposed. The reaction of acetylacetone with PBFA was also examined to give the polymer of 7.6 x 10(3) as the highest molecular weight catalyzed by sodium hydroxide at room temperature. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5698-5708, 2009