STUDY OF VINYLIDENE FLUORIDE (VF2) TELOMERIZATION AND COTELOMERIZATION .2. VF2 AND CHLOROTRIFLUOROETHYLENE (CTFE) COTELOMERIZATION WITH 2-HYDROXYETHYLMERCAPTAN BY RADICAL INITIATION

The radical telomerization of vinylidene fluoride (VF2) and of chlorot rifluoroethylene (CTFE) with 2-hydroxyethylmercaptan as the telogen wa s investigated. The corresponding homotelomers R-S-(CF2-CFCl)(n)-H (C- n) and R-S-(CH2-CF2)(n)-H (V-n) with R = -CH2CH2OH were synthesized an d the 1:1 adducts identified. The VF2/CTFE/thiol reaction gave a mixtu re of the expected products, homotelomers and cotelomers. By various m ethods, mainly by F-19 NMR spectroscopy, the chain length and tacticit y of these telomers were determined. For example, after analysis, a fr action of the cotelomers was in good agreement with the general formul a HO-CH2-CH2-S-(CF2-CFCl)(x)-(CH2-CF2)(y)-H, with x and y close to 4. Moreover, by comparison with the spectra of homotelomers of VF2 and CT FE, it was shown that these cotelomers exhibit an alternating structur e.