AQUEOUS EMULSION POLYMERIZATION OF FUNCTIONALIZED FLUOROMONOMER

• Main Authors: LOCHHAAS KAI H, MAERZ FRANZ, THALER ARNE, HAMROCK STEVEN J, HINTZER KLAUS
• Format: Patent
• Language: English
• Published: 26.07.2012
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PROBLEM TO BE SOLVED: To provide a sulfonic acid functionalized polymer that is useful in manufacturing of a polymer film of an electrolytic cell, such as a fuel cell.SOLUTION: A method is provided for aqueous emulsion copolymerization of two or more fluoromonomers including: (1) a step of forming an aqueous pre-emulsion by mixing a fluoromonomer expressed by formula (I), FC=CF-R-SOX (where, in the formula, Rrepresents a branched or unbranched perfluoroalkyl, perfluoroalkoxy, or perfluoroether group including 1 to 15 carbon atoms and 0 to 4 oxygen atoms, and X represents F, Cl, or Br), together with 0.001 to 0.9 molar equivalent of a base in the absence of added emulsifier; and (2) a step of forming a fluoropolymer latex containing a fluoropolymer in which more than 1 mol% of monomer units are derived from the fluoromonomer expressed by formula I, by reacting the pre-emulsion with one or more perfluorinated comonomers in the absence of added emulsifier.