Abstract
The synthesis of original highly fluorinated telomers containing 1,1,3,3,3-pentafluoropropylene (PFP, R1225ze), RF(C3HF5)nI [where n stands for 1 and 2 and RF corresponds to either C6F13 or (CF3)2CF] and their cotelomers of general formula: RF{[F2C-CH(CF3)]x-(CH2-CR1R2)y}zI, based on vinylidene fluoride H2C=CF2 (VDF) (R1=R2=F); 3,3,3-trifluoropropene, CH2=CHCF3, (TFP) (R1=H, R2=CF3), and tert-butyl 2-trifluoromethylacrylate (TFMA) (R1=CF3, R2=CO2tert-Bu) are presented. These (co)telomers were obtained from thermal initiation or in the presence of peroxides, in bulk and in solution (1,1,1,3,3-pentafluorobutane), leading to monoadduct and diadduct, the amounts of which depending upon the [RFI]0/[PFP]0 initial molar ratio (R0). The percentage of monoadduct increased up to 50-60% versus dimer (30-25%) at temperatures up to 143 °C with peroxides as the initiator (In) and initial c0=[In]0/[∑(Monomers)]0 molar ratios up to a degree of telomerization of 1.5. All the synthesized (co)telomers were characterized by 1H and 19F NMR spectroscopies and evidenced isomers. The molecular weights, ranging between 430 and 1500 g.mol-1 and molecular weight distributions were assessed by GPC (SEC) chromatography and NMR.