Synthesis of Perfluorinated Polyethers via Polyesters Deriving from the Hydrocarbons. A General Method

摘要

This paper reports on a new synthetic method which we consider to be truly general. It will open synthetic routes to literally hundreds of different perfluorinated ether and polyether structures. This synthetic technique involves the direct fluorination of polyesters followed by treatment with sulfur tetrafluoride to produce new perfluorinated polyethers, and in some cases hydrolysis to produce functional perfluorinated ethers. These new methods offer a number of extremely significant and important advantages. With this technique it is possible to prepare perfluorinated polyethers containing more than two carbon atoms between two oxygen atoms in the backbone. The technology of tetrafluoroethylene oxide and hexafluoropropylene oxide (i.e. polymerization of the perfluorovinyl epoxides) is limited to polymers containing two carbon atoms between the oxygen atoms in the main chain. A second important advantage is that perfluorinated polyethers with unsymmetrical repeating units are available (AOBOAOB), whereas with perfluorovinyl epoxides other than random copolymers, one must have repeating AOA structures. The new technique is also capable of producing highly branched ethers serving as potential elastometer and fluids of high thermal stability.