SYNTHESIS OF FLUORINATED TELOMERS .4. TELOMERIZATION OF VINYLIDENE FLUORIDE WITH COMMERCIALLY AVAILABLE ALPHA,OMEGA-DIIODOPERFLUOROALKANES

The synthesis of a new fluorinated alpha,omega-diiodo telomer I[(TFE)( x)(VDF)(y)]I (A), where TFE and VDF represent tetrafluoroethylene and vinylidene fluoride respectively, has been carried out by telomerizati on of VDF with alpha,omega-diiodoperfluoroalkanes. The thermal telomer ization of VDF with 1,2-diiodoperfluoroethane IC2F4I led to good yield s of the monoadduct IC2F4CH2CF2I and of the diadduct which was compose d of an almost equimolar ratio of ICF2CH2C2F4CH2CF2I and IC2F4(CH2CF2) (2)I, together with a small amount of IC2F4CH2CF2CF2CH2I and a triaddu ct containing I(VDF)C2F4(VDF)(2)I and IC2F4(VDF)(3)I. This procedure h as been applied successfully to alpha,omega-diiodo-n-perfluorobutane a nd alpha,omega-diiodo-n-perfluorohexane. The reactivity of VDF relativ e to the fluorinated alpha,omega-diiodo telogens has been studied from which it is shown that the environment of the terminal group of the t elogen is a major factor affecting the reactivity.