Telomerization of vinylidene fluoride with alkyl (or aryl) trifluoromethanethiosulfonates
Résumé
Abstract The photochemical‐induced telomerization of vinylidene fluoride (VDF) with cyclohexyl (or phenyl) trifluoromethanethiosulfonate (CF 3 SO 2 SR), leading to CF 3 (VDF) n SR telomers, where R stands for cyclohexyl or phenyl, is presented. These sulfurated transfer agents were synthesized by the reaction between sodium triflinate (CF 3 SO 2 Na) and disulfide in the presence of bromine. 19 F NMR spectroscopy enabled an assessment of the average degrees of telomerization (DP n ) of these telomers with a neat CF 3 end group as the label. These DP n values increased for higher [VDF] 0 /[CF 3 SO 2 SR] 0 initial molar ratios. Interestingly, the normal/reversed ratio of VDF units in these telomers was low. Finally, the cotelomerization of VDF and hexafluoropropylene with these transfer agents was successfully achieved, leading to original ω‐CF 3 fluoroelastomers, the thermal properties of which were investigated. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4538–4549, 2002