Cationic polymerization of 1H,1H,2H,2H perfluorooctyl vinyl ether (CH2=CH-O-C2H4-C6F13), initiated by the HI/ZnI2 system in 1,1,2 trichloro trifluoro ethane at -30-degrees-C, leads to living polyvinyl ethers bearing a fluoroalkyl group. Results indicate that the polymerization is indeed free from chain transfer and termination reactions and that polyethers of controlled molecular weight and a narrow molecular weight distribution can be made available.