Abstract
The radical copolymerization of two different methacrylate monomers, 2,2,2-trifluoroethyl-methacrylate (TFEMA) and tert-butyl-a-trifluoromethacrylate (TBTFMA) in solution was investigated. The resulting statistic poly(TFEMA-co-TBTFMA) copolymers were characterized by NMR spectroscopy to assess their compositions. The kinetics of copolymerization enabled one to determine the reactivity ratios of both comonomers according to the methods of Fineman-Ross, Kelen-Tu¨ dos, and extended Kelen-Tu¨ dos. Excellent correlations were found between these methods leading to the following reactivity ratios: rTFEMA ¼ 4.87 6 1.50 and rTBTFMA ¼ 0.10 6 0.02 at 74 C. These values indicated that the structure of the copolymers was composed of poly(TFEMA) micro-blocks separated by one TBTFMA unit. Both yields and molecular weights (ranging between 1000 and 12,000 g/mol) increased with the TFEMA content. The thermal stability of these (co)polymers showed that the decomposition temperature at 10% weight loss increased both with TFEMA content and increasing molecular weights of the poly(TFEMA-co-TBTFMA) copolymers.