A METHOD FOR PREPARING CARBONYLIC PERFLUOROPOLYETHERS

摘要

A process for preparing perfluoropolyethers of formula T-O-(R_F) _z-T' wherein: T, T' are end groups, z = 0 or 1; R_F is a perfluoro(poly)oxyalkylene chain containing one or more fluorooxyalkylene repeating units selected from (CF₂O), -(CF(CF₃)O)-, -(CF₂CF₂O)-, -(CF₂CF(CF₃)O)-, -(CF(CF₃)CF₂O)-, -(CF₂CF₂CF₂O)-, -(CF₂CF₂CF₂CF₂O)-, -(CF₂)_j-CFZ-O- wherein j is an integer from 0 to 3 and Z is a fluorooxyalkylene chain comprising from 1 to 20 repeating units selected from the above reported fluorooxyalkylene units; comprising the reduction of peroxidic perfluoropolyethers comprising one or more of the above defined repeating units by using gaseous hydrogen in the presence of a catalyst comprising one or more metals of the VIII group supported on graphitic materials.