Controlled Radical Polymerization Vs Conventional Radical Polymerization: Differences In Surface Properties Of 4 '-Nonafluorobutyl Styrene Polymers

4'-Nonafluorobutyl styrene was synthesized and polymerized by conventional and controlled radical polymerization (CRP) based on iodine transfer polymerization (ITP) technique. The fluorinated monomer was prepared from Ullmann coupling between 1-iodoperfluorobutane and 4'-nonafluorobutyl acetophenone followed by a reduction and a dehydration in overall 50% yield. The radical polymerization of 4'-nonafluorobutyl styrene was initiated by AIBN and controlled by 1-iodoperfluorohexane in 84% monomer conversion and in 50% yield. The benefits of ITP of 4'-nonafluorobutylstyrene featured (i) a fast monomer conversion, monitored by H-1 and F-19 NMR in the presence of 1,2-dichloroethane as the internal standard, (ii) the evolution of the ln([M](0)/[M]) versus time that evidenced a linear behavior. The square of the propagation rate to the termination rate (k(p)(2)/k(t)) of 4'-nonafluorobutyl styrene in ITP conditions was assessed (3.66 . 10(-2) L . mol(-1) . s(-1) at 80 degrees C) according to the Tobolsky's kinetic law. The polydispersity index of fluoropolymer achieved by conventional polymerization was 1.30 while it was reduced to 1.15 for that synthesized by the controlled way. The thermal stability of these oligomers was satisfactory (the 10% weight loss under air occurred from 305 degrees C) and the melting point was about 47 degrees C. Contact angles and surface energies assessed on surface spin-coated polymeric films made of poly(4'-nonafluorobutyl styrene) obtained by conventional (hysteresis = 18 +/- 2 degrees, surface energy 18 degrees +/- 2 degrees mN/m), and controlled radical polymerization (hysteresis = 47 degrees +/- 2 degrees, surface energy 15 +/- 2 mN/m) evidenced the influence of the PDI values with the surface properties of the synthesized polymers.