Free radical copolymerization of 2,2,2‐trifluoroethyl α‐fluoroacrylate and <i>tert</i>‐butyl α‐trifluoromethylacrylate: Thermal and optical properties of the copolymers

Abstract

Abstract The radical copolymerization of 2,2,2‐trifluoroethyl α‐fluoroacrylate (FATRIFE) with tert ‐butyl α‐trifluoromethylacrylate (MAF‐TBE) initiated by tert ‐butyl 2,2‐dimethylperoxypropanoate was investigated in acetonitrile solution. A series of poly(FATRIFE‐ co ‐MAF‐TBE) copolymers were synthesized with MAF‐TBE compositions, determined by 19 F NMR, ranging from 12 to 44 mol %. MAF‐TBE incorporation was less than 50 mol % as this monomer underwent no radical homopolymerization. The obtained copolymers exhibited number‐average molecular weights and polydispersity indexes ranging from 1.5 × 10 4 to 9.6 × 10 4 g/mol and from 1.5 to 3.1, respectively. The reactivity ratios were determined by the Kelen‐Tüdos method ( r FATRIFE = 1.71 ± 0.01 and r MAF‐TBE = 0 at 74 °C) leading to random copolymers and alternating copolymers when the MAF‐TBE molar ratio in copolymer is close to 50 mol %. Thermal and optical properties of the resulting polymers were examined. Glass transition temperatures of copolymers were varying from 89 to 108 °C. Modifying the compositions of these copolymers allowed a precise control over the refractive index measured at 633, 1320, and 1550 nm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4383–4391, 2008