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Peroxide initiated vinylidene fluoride (VDF) telomerization was investigated in the presence of bromine terminated perfluoropolyethers CF 3 (OCF 2 CF 2 ) m (OCF 2 ) p Br, (R f -Br). R f -Br act as telogen agents producing the above reaction compounds of general formula R f -(VDF) n Br. Data on telomer microstructure by fluorine NMR, glass transition temperature and crystallinity of (VDF) n moiety are also reported and discussed. The products show properties of di-block copolymers.

Fluorine containing alcohols, esters and ethers have been obtained by peroxide induced radical addition of alcohols, esters and ethers to 1,2-dichlorodifluoroethene. The influence of the kind and amount of the peroxide has been studied and the reactivity of alcohols, esters and ethers compared.

Vinylidene fluoride (VDF) telomerization has been investigated using 1,2-dibromotetrafluoroethane (I) in the presence of different initiators as telogen. End groups determined by NMR spectroscopy show the different role of the initiator radicals in the telemerization process. The presence of short branch structures, formed by intramolecular transfer, has been demonstrated through 13 C, 19 F and 1 H NMR spectroscopy.

Liquid phase fluorination of diethyleneglycol dimethyl ether tetraethyleneglycol dimethyl ether, 2[1,2-dichloro-1,2-difluoroethyl] tetrahydrofuran and 2[1,2-dichloro-1,2-difluoroethyl] dioxane 1,4 produce the corresponding perfluoroethers in 56, 43, 67 and 74 % yields respectively. The by-products are partially fluorinated compounds and no fragmentation is observed. The simplicity of the reactions and method of preparation make this approach to fluorinated fluids and oils industrially attractive.

Elimination of hydrogen fluoride, using antimony pentafluoride, is a useful preparative process for some fluorinated alkenes and presents a new and simple approach to conjugated polymers.

Radical reactions of 1,1-difluoroethene (VDF) in the presence of halogenated telogens RX have been widely investigated in the literature; they give products of general formula R(CH2CF2)nX where n ranges mainly from 2 to 8 [1]. The present work is concerned with the study of peroxide induced telomerization of vinylidene difluoride in the presence of bromofluoroethanes as CF3CF2 Br, CF3CFBr2 and CF2BrCF2Br. Reactions were carried out at 150°C in the presence of di-tert-butylperoxide (0.5–40 mol % based on VDF) with telogen/VDF molar ratios ranging from 1/20 to 5/1. Liquid, waxy and solid telomers are obtained with n < 30. The different behaviour of the telogens is also reported and discussed. For instance in the same reaction conditions CF3CF2Br gives n values higher than CF2BrCF2Br. The structure of the telomers has been determined by 19F and 1H NMR spectroscopy. Glass transition temperatures of the telomers are reported and discussed.