Method for the electrolytic decarboxylation of a perfluorocarboxylic acid or soluble salts thereof, and subsequent dimerisation of the radicals so formed

摘要

The invention relates to a method for the electrolytic decarboxylation of a perfluoro carboxylic acid of the formula (I) IMAGE with x = 1 to 4 or of soluble salts of this acid or of a mixture of this acid or of these salts with another perfluoro carboxylic acid of the formula (II) IMAGE with y = 0 to 4 or the soluble salts thereof and subsequent dimerisation of the radicals produced in the decarboxylation. The electrolysis is carried out in methanol or methanol/water mixtures. This results in perfluoropolyethers of the formula IMAGE or a mixture of symmetrical and asymmetrical perfluoropolyethers when more than one perfluoro carboxylic acid is employed.