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Synthesis of new linear perfluoroalkyl polyethers starting from diols and tetrafluoroethylene

New linear perfluoropolyalkylethers (PFPEs) with regularly sequenced repeat units are prepared by a four‐step synthesis starting from simple glycols and tetrafluoroethylene. The synthesis includes: (i) the reaction of glycols with tetrafluoroethylene to give bis(tetrafluoroethyl)alkyl ethers, (ii) the dehydrofluorination of the adduct with butyllithium to obtain bis(trifluorovinyl)alkyl ethers, (iii) the polymerisation of the trifluorovinyl ethers with glycols in the presence of base to make polyfluoroalkyl polyethers, and (iv) finally the fluorination of the polymers to provide PFPEs. The repeat units of the final PFPEs are altered by the variation of diols used in steps 1 and 3. Copyright © 2010 John Wiley & Sons, Ltd.