Verfahren zur Herstellung von perfluoropolyoxyalkylene mit OCF2H, OCF2CF2H oder OCF(CF3)H Endgruppen

• Main Authors: SPATARO, GIANFRANCO, MARCHIONNI, GIUSEPPE
• Format: Patent
• Language: German
• Published: 29.01.2009
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC CHEMISTRY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

A process for preparing perfluoropolyoxyalkylenes having -OCF2H, -OCF2CF2H and -OCF(CF3)H end groups and a number average molecular weight from 120 to 3,000, by decarboxylation of the corresponding perfluoropolyoxyalkylenes having -OCF2COOH, -OCF2CF2COOH, -OCF(CF3)COOH end groups, in the presence of catalytic amounts of salts formed by perfluoropolyoxyalkylenes having end groups selected from -OCF2COOZ, -OCF2CF2COOZ and -OCF(CF3)COOZ, wherein Z is a monovalent cation of the group Ia or Ib or Z is -NR4<+> wherein R is hydrogen or a C1-C4 alkyl, using ratios between Z and the -COOH equivalents of the perfluoropolyoxyalkylenes to be decarboxylated from 0.01 to 0.08, at a temperature between 120 DEG C and 180 DEG C, in the presence of water, at pH < 5 and at a pressure comprised between 2 and 80 atmospheres.