Abstract: The invention pertains to a fluoroelastomer composition comprising: at least one fluoroelastomer [perfluoroelastomer (A)], said fluoroelastomer (A) comprising iodine and/or bromine atoms and having a backbone comprising: recurring units derived from tetrafluoroethylene (TFE); recurring units derived from at least one perfluorinated monomer selected from the group consisting of: perfluoroalkylvinylethers complying with formula CF2?CFORf1 in which Rn is a C1-C6 perfluoroalkyl (monomers of this type being referred to, herein after, as PAVE), e.g. —CF3, —C2F5, —C3F7; perfluoro-oxyalkylvinylethers complying with formula CF2?CFOX0, in which X0 can be (i) a C1-C12 perfluorooxyalkyl having one or more ether groups, e.g. —C2F5—O—CF3; or (ii) a group of formula —CF2ORf2 in which Rf2 is a C1-C6 perfluoroalkyl, e.g.

Abstract: The invention pertains to a fluoroelastomer composition comprising:—at least one fluoroelastomer [perfluoroelastomer (A)], said fluoroelastomer (A) comprising iodine and/or bromine atoms and having a backbone comprising:—recurring units derived from tetrafluoroethylene (TFE);—recurring units derived from at least one perfluorinated monomer selected from the group consisting of:—perfluoroalkylvinylethers complying with formula CF2?CFORf1 in which Rn is a C1-C6 perfluoroalkyl (monomers of this type being referred to, herein after, as PAVE), e.g. —CF3, —C2F5, —C3F7;—perfluoro-oxyalkylvinylethers complying with formula CF2=CFOX0, in which X0 can be (i) a C1-C12 perfluorooxyalkyl having one or more ether groups, e.g. —C2F5—O—CF3; or (ii) a group of formula —CF2ORf2 in which Rf2 is a C1-C6 perfluoroalkyl, e.g.

Abstract: The invention pertains to a semi-crystalline fluoropolymer having ion exchange groups comprising recurring units derived from at least one ethylenicalty unsaturated monomer comprising at least one fluorine atom (fluorinated monomer); and a substantial amount of recurring units derived from at least one ethylenically unsaturated monomer comprising at least one ion exchange group (functional monomer), wherein the amount of unstable end groups of —COF type is of less than 0.05 mmol/kg, and the use of the stabilized fluoropolymer in fuel cells devices, a membrane and a membrane-electrode assembly.

Abstract: The invention pertains to a process for stabilizing a semi-crystalline fluoropolymer comprising ion exchange groups, said process comprising: suspending at least one semi-crystalline fluoropolymer having ion exchange groups [polymer (I)] in at least one fluorinated organic dispersing medium [medium (M)] so as to obtain a dispersion (D) of polymer (I) in a dispersing medium (M); contacting said dispersion (D) with fluorine under irradiation with U. V. radiation so as to obtain a stabilized polymer. Still objects of the invention are a stable semi-crystalline fluoropolymer as above defined having a low amount of unstable ends groups of —COF type, the use of the stabilized fluoropolymer obtained by the process or of the stable fluoropolymer in fuel cells devices, a membrane and a membrane-electrode assembly comprising said fluoropolymers.

Abstract: The invention pertains to a process for stabilizing a semi-crystalline fluoropolymer comprising ion exchange groups, said process comprising: suspending at least one semi-crystalline fluoropolymer having ion exchange groups [polymer (I)] in at least one fluorinated organic dispersing medium [medium (M)] so as to obtain a dispersion (D) of polymer (I) in a dispersing medium (M); contacting said dispersion (D) with fluorine under irradiation with U.V. radiation so as to obtain a stabilized polymer. Still objects of the invention are a stable semi-crystalline fluoropolymer as above defined having a low amount of unstable ends groups of —COF type, the use of the stabilized fluoropolymer obtained by the process or of the stable fluoropolymer in fuel cells devices, a membrane and a membrane-electrode assembly comprising said fluoropolymers.

Abstract: The invention pertains to a process for stabilizing a semi-crystalline fluoropolymer comprising ion exchange groups, said process comprising: suspending at least one semi-crystalline fluoropolymer having ion exchange groups [polymer (I)] in at least one fluorinated organic dispersing medium [medium (M)] so as to obtain a dispersion (D) of polymer (I) in a dispersing medium (M), contacting said dispersion (D) with fluorine under irradiation with U.V. radiation so as to obtain a stabilized polymer. Still objects of the invention arc a stable semi-crystalline fluoropolymer as above defined having a low amount of unstable ends groups of —COF type, the use of the stabilized fluoropolymer obtained by the process or of the stable fluoropolymer in fuel cells devices, a membrane and a membrane-electrode assembly comprising said fluoropolymers.