The invention relates to aqueous dispersions of fluoropolymers comprising recurring units derived from vinylidene fluoride (VDF) in an amount of from 60% to 82% in moles and recurring units derived from trifluoroethylene (TrFE) in an amount of from 18% to 40% in moles, with respect to the total moles of recurring units, said fluoropolymers possessing an improved thermodynamic ordered structure in the ferroelectric phase.

A member to be compressed for an electrochemical device obtained by crosslinking a crosslinkable composition containing a fluorine-containing elastomer containing a unit based on at least one crosslinkable group-containing monomer selected from the group consisting of a crosslinkable group-containing monomer (1) represented by the general formula (1):

CX.sup.1.sub.2═CF—Rf.sup.1—X.sup.2

wherein each X.sup.1 independently represents H or F, and Rf.sup.1 represents a fluorinated alkylene group or a fluorinated oxyalkylene group, and X.sup.2 represents I or Br; and a crosslinkable group-containing monomer (2) represented by the general formula (2):

CX.sup.3.sub.2═CX.sup.3—Z.sup.1—CX.sup.3═CX.sup.3.sub.2

wherein each X.sup.3 independently represents H, F, an alkyl group or a fluorinated alkyl group, and Z.sup.1 represents an alkylene group, a fluorinated alkylene group, a cycloalkylene group, a fluorinated cycloalkylene group, an oxyalkylene group or a fluorinated oxyalkylene group.

A member to be compressed for an electrochemical device obtained by crosslinking a crosslinkable composition containing a fluorine-containing elastomer containing a unit based on at least one crosslinkable group-containing monomer selected from the group consisting of a crosslinkable group-containing monomer (1) represented by the general formula (1):

CX.sup.1.sub.2═CF—Rf.sup.1—X.sup.2

wherein each X.sup.1 independently represents H or F, and Rf.sup.1 represents a fluorinated alkylene group or a fluorinated oxyalkylene group, and X.sup.2 represents I or Br; and a crosslinkable group-containing monomer (2) represented by the general formula (2):

CX.sup.3.sub.2═CX.sup.3—Z.sup.1—CX.sup.3═CX.sup.3.sub.2

wherein each X.sup.3 independently represents H, F, an alkyl group or a fluorinated alkyl group, and Z.sup.1 represents an alkylene group, a fluorinated alkylene group, a cycloalkylene group, a fluorinated cycloalkylene group, an oxyalkylene group or a fluorinated oxyalkylene group.

Described herein is a composition comprising a fluorothermoplastic polymer, wherein the fluorothermoplastic polymer is derived from: (a) 60-85 mol % tetrafluoroethene; (b) 2-12 mol % hexafluoropropene; (c) 10-30 mol % vinylidene fluoride; (d) 0.2 to 5 mol % of a bromine-containing monomer. Such compositions can be used in multilayer constructions in, for example, fuel hose applications.

Described herein is a composition comprising (i) a hydrofluorothermoplastic polymer, wherein the hydrofluorothermoplastic polymer is derived from: (a) 50-85 mol % tetrafluoroethene; (b) 2-15 mol % hexafluoropropene; (c) 10-35 mol % vinylidene fluoride; and (d) 0.1 to 5 mol % of a bromine-containing monomer; and (ii) a perhalogenated thermoplastic polymer. Such compositions can be used in multilayer constructions in, for example, fuel hose applications.

A fluorine-containing elastomer including a vinylidene fluoride unit and an unsaturated ether unit selected from a unit based on a monomer (1) represented by the general formula (1): CH.sub.2═CFCF.sub.2—O—Rf.sup.1 and a unit based on a monomer (2) represented by the general formula (2): CH.sub.2═CF—O—Rf.sup.2, and having a glass transition temperature of 20° C. or lower, a crosslinkable composition including the fluorine-containing elastomer, and a molded article obtained from the fluorine-containing elastomer or the crosslinkable composition.

A fluorine-containing elastomer including a vinylidene fluoride unit and an unsaturated ether unit selected from a unit based on a monomer (1) represented by the general formula (1): CH.sub.2═CFCF.sub.2—O—Rf.sup.1 and a unit based on a monomer (2) represented by the general formula (2): CH.sub.2═CF—O—Rf.sup.2, and having a glass transition temperature of 20° C. or lower, a crosslinkable composition including the fluorine-containing elastomer, and a molded article obtained from the fluorine-containing elastomer or the crosslinkable composition.

The invention relates to an anode for a Li-ion rechargeable battery, said anode being covered with a protective film based on fluorinated copolymer(s). The invention also relates to the processes for preparing this anode. The invention also relates to a Li-ion rechargeable battery comprising an anode according to the invention. The invention lastly relates to the use of fluorinated copolymer(s) as film for covering an anode for a lithium-ion battery comprising a negative electrode active material.

Described herein is method of making branched perfluorinated compounds, specifically (CF.sub.3).sub.2CFCF(CF.sub.3)OCF(CF.sub.3)C(═O)F and (CF.sub.3).sub.2CFCF(CF.sub.3)OCF═CF.sub.2. Also disclosed herein is a fluoropolymer derived from the branched perfluorovinyl ether monomer and methods of making the fluoropolymer.

Copolymers of one or more halogenated olefins and one or more halogenated co-monomers selected from the group consisting of halogenated alkenyl ethers, halogenated alkenyl esters, and halogenated (meth)acrylates are useful in various end-use applications wherein the presence of halogen (e.g., fluorine) in the copolymer imparts one or more desirable properties, as compared to analogous copolymers not containing halogen.