Copolymers based on 2,2,2-trifluoroethyl methacrylate (MATRIFE) and 2,2,2-trichlororoethyl alpha-fluoroacrylate (FATRICE) were synthesized in good yields by radical process initiated by tert-butyl 2,2-dimethylperoxypropanoate. Molar composition of the obtained poly(MATRIFE-co-FATRICE) copolymers were assessed by means of H-1 and F-19 nuclear magnetic resonance spectroscopy and by elemental analysis. The reactivity ratios, r(i), of both comonomers were determined from the Kelen-Tudos and Finneman-Ross methods (r(MATRIFE) = 1.52 +/- 0.03 and r(FATRICE) = 0.61 +/- 0.03 at 74 degrees C) showing unexpectedly that MATRIFE is the more reactive monomer in copolymerization. Molecular weights and polydispersity indexes of poly(MATRIFE-co-FATRICE) copolymers were ranging between 1.47 and 2.68 x 10(4) g.mol(-1) and from 1.44 to 2.21, respectively. Thermal properties of the resulting polymers were examined and thermogravimetric analyses showed a satisfactory thermal stability, a thermal decomposition occurring from 220 to 295 degrees C as the molar ratio of FATRICE increased in the copolymer. Moreover, the glass transition temperatures of copolymers varied from 66 to 108 degrees C and also increased with FATRICE molar ratio in the copolymers. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2154-2161, 2010