Functionalized fluorinated polymer and method of its preparation

Abstract

The present invention relates to a polymer P1 comprising residues of a fluorinated monomer and a segment containing a -PO2X group. The present invention also relates to a process for preparing said polymer and its use in a separator or as an electrode binder in electrochemical devices.

Description

Title of the invention: Functionalized fluorinated polymer and method of preparing the same Technical field

[0001] The present invention relates generally to the field of electrical energy storage in rechargeable secondary batteries of the Li-ion type. More specifically, the invention relates to a composition suitable for use as a cathode or anode binder or as a coating for a separator. Technological background of the invention

[0002] Lithium-ion batteries comprise a cathode which comprises a mixture of a lithiated metal oxide, a conductive filler (generally carbon black) and a polymer binder. This mixture is deposited on a metal sheet, generally pre-coated aluminum or not depending on its specific use (LFP, LMPF, NMC or other). The polymer binder ensures the cohesion of the deposited layer and its adhesion to the metal sheet. It is known to use poly(vinylidene fluoride) as a binder for the cathode.

[0003] Functional poly(vinylidene fluoride) are materials with interesting properties, the functionality of the polymer can improve performances such as peeling and mechanical strength. The polymer can be functionalized with maleic anhydride or polyacrylic acid. This type of polymer has gained importance in separator coating applications for lithium-ion batteries.

[0004] The presence of the acid functionality is important to promote adhesion between the constituent materials of the electrode, in particular adhesion with the active materials. In addition, the structure and distribution of the acid functionality is another important factor. The acid functionality can be introduced by different means: grafting, introduction of a monomer, an oligomer or a polymer by chemical reactions. It is known in particular from document US20180072829 that polyacrylic acid can be bonded to the fluoropolymer and improves the adhesion properties of the polymer. There is still a need to provide new functionalized fluoropolymers and new methods for introducing the desired functionalizations within the fluoropolymer. Summary of the invention

[0005] According to a first aspect, the present invention provides a polymer PI comprising residues of a fluorinated monomer Ml comprising a C=C double bond and at least one fluorine atom and one or more segment(s) SI selected from the formulae (la), (Ib), (le), (Id), (le), (If) and (Ig) or a mixture of these

[0006] -P(O)(OX)-[CR1R2CR3((X1)PC(O)R4)-(P(O)(OX))r]n- (la)

[0007] -P(O)(OX)-[CR* R2 CR3 (OC(O)R4)-(P(O)(OX))r]n- (Ib)

[0008] -P(O)(OX)-[CR20R21CR22C(O)OC(O)CR23CR24R25-(P(O)(OX))r]n- (the) dOTOXJP (THE)

[0009] -P(O)(OX)-[CR36R37CR38(CN)-(P(O)(OX))r]n- (If)

[0010] -P(O)(OX)-[CR39R40CR41(C(O)NR42R43)-(P(O)(OX))r]n- (Ig)

[0011] in which

[0012] R1, R2, R3 are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, C1-C5 alkyl;

[0013] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl;

[0014] R4' is CrC5 alkyl;

[0015] n is an integer between 1 and 50000, advantageously between 2 and 40000, preferably between 3 and 30000, more preferably between 4 and 20000, in particular between 5 and 10000, more particularly between 5 and 5000, preferably between 5 and 3000;

[0016] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0017] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16, R17, R18, R19 are independently of each other and independently for each unit w selected from the group consisting of H and C1-C5 alkyl;

[0018] R4 is, independently for each unit n, selected from the group consisting of -NHC(CH3)2CH2C(O)CH3 and -OR5 with R5 selected from the group consisting in H and CrCi8 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five or six-membered heterocycle comprising at least one nitrogen atom in its cyclic chain;

[0019] R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups;

[0020] r is, independently for each unit n, 0 or 1;

[0021] p, independently for each unit n, is 0 or 1;

[0022] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0023] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and Ci-Cio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0024] The present invention therefore provides a polymer PI comprising a block derived from a fluorinated monomer and a block being said segment SI which is preferably hydrophilic. The segment SI forms a block linked to one or two blocks comprising the fluorinated monomer M1 as a residue (i.e. as a repeating unit) or optionally the monomer M1' or the monomer M1” as defined in the present application. The segment SI has at least one phosphorylated function which links with the block derived from one of the monomers M1, M1' or M1”. The segment SI and the phosphorylated function make it possible to improve adhesion and the phosphorylated function can also act as an antioxidant in order to prevent coloring of the polymer. In addition, the segment SI can also act as a surfactant or dispersant during the implementation of the polymerization process, optionally in combination with other dispersants or surfactants.

[0025] According to a preferred embodiment, said fluorinated monomer Ml is selected from the group consisting of vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2 CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3 H; a monomer of formula CF2=CFOCF2CF2SO2F; a monomer of formula F(CF2) nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2 OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof.

[0026] According to a preferred embodiment, said fluorinated monomer M1 is vinylidene fluoride and said polymer PI optionally comprises residues of a monomer M1' selected from the group consisting of vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2CF2 SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2 )m and m is 1, 2, 3 or 4;the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-1-propene or a mixture thereof. ;

[0027] According to a preferred embodiment, said polymer PI comprises residues of a monomer M1” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) or a mixture thereof

[0028] R6R7C=C(R8)((X2)PC(O)R10) (II)

[0029] RnR12C=C(R13)(OC(O)R14) (III)

[0030] R20 R21 C=CR22 C(O)OC(O)CR23=CR24 R25 (IV) (Vj (VI)

[0031] R36 R37'c=CR38'(CN) (VII)

[0032] R39 R40 C=CR41 (C(O)NR42 R43) (VIII)

[0033] in which

[0034] R6, R7 and R8 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0035] R10 is, independently for each unit n, selected from the group consisting of in -NHC(CH3)2CH2C(O)CH3 and -OR5' with R5' selected from the group consisting of H and C1-C18 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0036] R9' is selected from the group consisting of C1-C5 alkyl and C6-C12 substituted aryl by one or more CO2H functional groups;

[0037] X2 is selected from the group consisting of -[-C(O)OC(R16')(R17')C(R18')(R19')-] wl- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16', R17, R18', R19' are (independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl;

[0038] p' is 0 or 1;

[0039] R11, R12 and R13 are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0040] R14 is C1-C5 alkyl;

[0041] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R 37', R38', R39', R40' and R41' are independently selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0042] R42' and R43' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0043] According to a preferred embodiment, said one or more segment(s) SI is se selected from formulas (la), (Ib), (le), (Id), (le), (If) and (Ig) as defined above or a mixture thereof; in which

[0044] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, C1-C3 alkyl;

[0045] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl;

[0046] R4' is CrC3 alkyl;

[0047] n is an integer between 1 and 5000, advantageously between 2 and 4000, preferably between 3 and 3000, more preferably between 4 and 2000, in particular between 5 and 1000, more particularly between 5 and 500;

[0048] R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and CrCi8 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, CO2H, -OPO32, -C(O)OR9, -OC(O)R9 and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0049] R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups;

[0050] r is, independently for each unit n, 0 or 1;

[0051] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0052] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16, R17, R18, R19 are independently of each other, independently for each unit w selected from the group consisting of H and C1-C3 alkyl;

[0053] p, independently for each unit n, is 0 or 1;

[0054] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0055] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrCio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0056] According to a preferred embodiment, said one or more segment(s) SI is selected from formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) as defined above or a mixture thereof; in which

[0057] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, C02H, C1-C3 alkyl;

[0058] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl;

[0059] R4' is CrC3 alkyl;

[0060] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 25 and 100, more particularly between 5 and 50;

[0061] R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9 and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0062] R9 is selected from the group consisting of C1-C3 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups;

[0063] r is, independently for each unit n, 0 or 1;

[0064] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0065] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 10; R16, R17, R18, R19 are H;

[0066] p, independently for each unit n, is 0 or 1;

[0067] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0068] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrCio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0069] According to a preferred embodiment, said polymer PI comprises one or more segment(s) SI selected from the group consisting of:

[0070] -P(O)(OX)-[CH(CO2H)CH(CO2H)-(P(O)(OX))r]n-,

[0071] -P(O)(OX)-[CH2CH(CO2H)-(P(O)(OX))r]n-,

[0072] -P(O)(OX)-[CH2C(CH3)(CO2H)-(P(O)(OX))r]n-,

[0073] -P(O)(OX)-[CH2CH(CO2CH3)-(P(O)(OX))r]n-,

[0074] -P(O)(OX)-[CH2C(CH3)(CO2CH3)-(P(O)(OX))r]n-,

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099] -P(O)(OX)-[CH2CH(CO2CH2CH2OH)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH(OH)CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH(CH3)CH2(OH))-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2-O-C(O)-CH2CH2CO2H)-(P(OX -P(O)(OX)-[CH2CH(CO2CH2CH2-O-C(O)-C6H4CO2H)-(P(O^ -P(O)(OX)-[CH2CH(CO2CH2CH2CH2CH(CO2H)CH2CH2CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH(CH3)2)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2C4H9)-(P(OX -P(O)(OX)-[CH2C(CH3)(CO2C5H11)XP(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH(CH3)2)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2C4H9)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2C5H11)-(P(O)(OX))r]n-, -P(O)(OX)-[CH(CH3)CH(CO2H)-(P(O)(OX))r]n-, -P(OXOX)-[CH2C(CH2CO2HXCO2H)-(P(OXOX))r]n-, -P(O)(OX)-[CH2CH((CO2CH2CH2)wCO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CN)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(C(O)NH2)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH2CH2OPO32)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(NHC(CH3)2CH2SO3H)XP(O)(OX))r]n-, -P(OXOX)-[CH2C(CH3XCO2C(O)OC(CH3)=CH2)-(P(OXOX))r]n-, 40M0X)P (KQXOW H H X' 0'

[0100]

[0101] -P(O)(OX)-[CH2CH(C(O)NHCH2OH)-(P(O)(OX))r]n-or a mixture thereof;

[0102] in which r is, independently for each unit n, 0 or 1;

[0103] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0104] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50. According to a preferred embodiment, said one or more segment(s) SI is covalently linked to at least one residue of said fluorinated monomer Ml or Ml' if present or Ml” if present via a functional group -P(O)(OX) of said segment SI; X is, independently for each unit n, selected from the group consisting of H, Na, K and Li.

[0105] According to another aspect, the present invention provides a process for preparing said polymer PI according to the present invention, characterized in that it comprises, in a reactor, a step of polymerization in aqueous medium of said fluorinated monomer Ml as defined in the present application in the presence of a compound SI' comprising one or more segment(s) SI according to the present invention.

[0106] According to a preferred embodiment, said compound SI' is obtained by reaction between an aqueous solution comprising hypophosphorous acid or a hypophosphite salt [H2P(O)(O )]xMy+ and one or more monomer(s) Ml” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) as defined in the present application, or a mixture thereof; M is H, an alkali or alkaline earth metal; and x and y are 1 if M is H or an alkali metal or x and y are 2 if M is an alkaline earth metal.

[0107] According to a preferred embodiment, said fluorinated monomer Ml is vinylidene fluoride and optionally the polymerization step is carried out in the presence of a monomer Ml' as defined in the present application; or of a monomer Ml” as defined in the present application.

[0108] According to another aspect, the present invention provides a composition comprising said polymer PI according to the present invention and a fluoropolymer P2 or a hydrophilic polymer P3 or a mixture of both polymers P2 and P3;

[0109] said fluorinated polymer P2 being selected from the group consisting of vinylidene fluoride homopolymer or vinylidene fluoride copolymer with a monomer M2 selected from the group consisting of vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2 =CFOCF2CF2SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-1-propene or a mixture thereof;

[0110] said hydrophilic polymer P3 comprising residues of a monomer M3 of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) as defined in the present application. Said polymers P2 and P3 are different from said polymer PI according to the present invention. Said polymers P2 and P3 do not contain segment(s) SI.

[0111] According to another aspect, the present invention provides a separator for an electrochemical device selected from the group: Li-ion, capacitor, electric double layer capacitor, and membrane electrode assembly (MEA) for fuel cell, said separator comprising a porous support and said PI polymer according to the present invention or said composition according to the present invention.

[0112] According to another aspect, the present invention provides a Li-ion secondary battery comprising an anode, a cathode and a separator, wherein said separator is according to the present invention.

[0113] According to another aspect, the present invention provides a binder for a Li-ion battery comprising said PI polymer according to the present invention or said composition according to the present invention.

[0114] According to another aspect, the present invention provides an electrode for a lithium-ion battery comprising a metal collector of which at least one face is covered with a substrate layer containing an active substance and a binder, characterized in that said binder is according to the present invention.

[0115] According to another aspect, the present invention provides a Li-ion secondary battery comprising an anode, a cathode and a separator, wherein the anode or the cathode is an electrode according to the present invention. Detailed description of the invention

[0116] According to a first aspect of the present invention, a polymer PI comprising residues of a fluorinated monomer Ml is provided. Said fluorinated monomer Ml comprises a C=C double bond and at least one fluorine atom. The term residue refers to a constituent unit of the polymer or a monomeric unit derived from the monomer in question. PI Polymer

[0117] Fluorinated monomer Ml

[0118] According to one embodiment, said fluorinated monomer M1 is selected from the group consisting of vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers, perfluoro(1,3-dioxole), perfluoro(2,2-dimethyl-1,3-dioxole), the monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H, the monomer of formula CF2=CFOCF2CF2SO2F, the monomer of formula F(CF2)nCH2 OCF=CF2 in which n is 1, 2, 3, 4 or 5, the monomer of formula R'CH2OCF=CF2 in which R1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4, the monomer of formula R2OCF=CH2 in which R2 is F(CF2)p and p is 1, 2, 3 or 4, perfluorobutyl ethylene, trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene,chlorotrifluoropropene, 2-trifluoromethyl-3,3,3-trifluoro-l-propene. Among the trifluoropropenes, mention may be made of 3,3,3-trifluoropropene. Among the tetrafluoropropenes, mention may be made of 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene. Among the pentafluoropropenes, mention may be made of 1,1,3,3,3-pentafluoropropene or 1,2,3,3,3-pentafluoropropene. Chlorofluoroethylene may refer to either 1-chloro-l-fluoroethylene or 1-chloro-2-fluoroethylene. The 1-chloro-l-fluoroethylene isomer is preferred. Chlorotrifluoropropene is preferably 1-chloro-3,3,3-trifluoropropene or 2-chloro-3,3,3-trifluoropropene.

[0119] Preferably, said fluorinated monomer Ml is selected from the group consisting of vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers, perfluoro(1,3-dioxole), perfluoro(2,2-dimethyl-1,3-dioxole), the monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H, the monomer of formula CF2=CFOCF2CF2SO2F, the monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5, the monomer of formula R'CH2OCF=CF2 in which R1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4, the monomer of formula R2OCF=CH2 in which R2 is F(CF2)p and p is 1, 2, 3 or 4.

[0120] More preferably, said fluorinated monomer Ml is selected from the group consisting of vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene.

[0121] In particular, said fluorinated monomer Ml is vinylidene fluoride.

[0122] In the PI polymer, the mass content of vinylidene fluoride units is at least 50%, preferably at least 60%, more preferably greater than 70% and advantageously greater than 80% based on the total weight of said PI polymer.

[0123] According to another preferred embodiment, said fluorinated monomer Ml is vinylidene fluoride and said polymer PI optionally comprises residues of a monomer Ml' selected from the group consisting of vinyl fluoride; trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2CF2SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2 )p and p is 1, 2, 3 or 4;perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof. ;

[0124] Preferably, said polymer PI comprises residues of said fluorinated monomer Ml being vinylidene fluoride and residues of the monomer Ml' selected from the group consisting of vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(methyl vinyl)ether (PMVE), perfluoro(ethyl vinyl)ether (PEVE), perfluoro(propyl vinyl)ether (PPVE), perfluoro(1,3-dioxole), perfluoro(2,2-dimethyl-1,3-dioxole) (PDD), a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2CF2 SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2 )m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE);trifluoropropene, tetrafluoropropene, pentafluoropropene, chlorotrifluoropropene or a mixture thereof. ;

[0125] In particular, said polymer PI comprises residues of said fluorinated monomer Ml being vinylidene fluoride and residues of the monomer Ml' selected from the group consisting of vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene and hexafluoropropylene, or a mixture thereof.

[0126] More particularly, said polymer PI comprises residues of said fluorinated monomer Ml being vinylidene fluoride and residues of the monomer Ml' selected from the group consisting of trifluoroethylene, chlorotrifluoroethylene, tetrafluoro- roethylene and hexafluoropropylene, or a mixture thereof.

[0127] The monomer Ml' may be present in a content of 1 to 50%, advantageously of 2 to 30% by weight relative to the weight of said polymer PI.

[0128] According to one embodiment, the polymer PI comprises residues of vinylidene fluoride (VDF) and hexafluoropropylene (HFP) (P(VDF-HFP)), having a percentage by weight of hexafluoropropylene monomer units of 2 to 30%, advantageously of 2 to 25%, preferably of 2 to 20%, preferably of 4 to 15% by weight relative to the weight of said polymer PI. According to another embodiment, the polymer PI comprises residues of vinylidene fluoride (VDF) and hexafluoropropylene (HFP) (P(VDF-HFP)), having a percentage by weight of hexafluoropropylene monomer units of 10 to 30%, advantageously of 10 to 25% by weight relative to the weight of said polymer PI.

[0129] According to one embodiment, the polymer PI comprises residues of vinylidene fluoride (VDF) and tetrafluoroethylene (TFE).

[0130] According to one embodiment, the polymer PI comprises residues of vinylidene fluoride (VDF) and chlorotrifluoroethylene (CTFE).

[0131] According to one embodiment, the polymer PI comprises residues of vinylidene fluoride, tetrafluoroethylene and trifluoroethylene. In this case, the mass content of vinylidene fluoride is at least 10%, the comonomers being present in variable proportions.

[0132] According to a preferred embodiment, said polymer PI comprises residues of a monomer M1” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) or a mixture thereof

[0133] R6R7C=C(R8)((X2)P-CO2R10) (II)

[0134] RnR12C=C(R13)(OC(O)R14) (III)

[0135] R20 R21 C=CR22 C(O)OC(O)CR23=CR24 R25 (IV) O (V) (VI)

[0136] R36'R37'C=CR38'(CN) (VII)

[0137] R39 R40 C=CR41 (C(O)NR42 R43) (VIII)

[0138] in which

[0139] R6, R7 and R8 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0140] R10 is, independently for each unit n, selected from the group consisting of in -NHC(CH3)2CH2C(O)CH3 and -OR5' with R5' selected from the group consisting of H and CrCi8 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0141] R9' is selected from the group consisting of C1-C5 alkyl and C6-C12 substituted aryl by one or more CO2H functional groups;

[0142] X2 is selected from the group consisting of -[-C(O)OC(R16')(R17')C(R18')(R19')-] wr and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16', R17, r18' rj v are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl;

[0143] p' is 0 or 1;

[0144] R11, R12 and R13 are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0145] R14 is CrC5 alkyl;

[0146] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R 37', R38', R39', R40' and R41' are independently selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0147] R42' and R43' are, independently of each other and independently for each unit n, selected from the group consisting of H and CrCio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0148] An ester group(s) as defined in the present application is of formula -OC(O)R15 with R15 being C1-C5 alkyl and C6-C12 aryl substituted by one or more CO2H functional groups.

[0149] Preferably, said polymer PI comprises residues of a monomer M1” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) or a mixture thereof.

[0150] in which

[0151] R6, R7 and R8 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0152] R10 is, independently for each unit n, selected from the group consisting of in -NHC(CH3)2CH2C(O)CH3 and -OR5' with R5' selected from the group consisting of H and Ci-Cio alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0153] R9' is selected from the group consisting of C1-C5 alkyl and C6-C12 substituted aryl by one or more CO2H functional groups;

[0154] X2 is selected from the group consisting of -[-C(O)OC(R16')(R17')C(R18')(R19')-] wl- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5;

[0155] R16', R17', R18', R19' are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C3 alkyl;

[0156] p' is 0 or 1;

[0157] R11, R12 and R13 are independently of each other selected from the group consisting of H and C1-C3 alkyl;

[0158] R14 is C1-C5 alkyl;

[0159] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R 37', R38', R39', R40' and R41' are independently selected from the group consisting of H and CrC3 alkyl, preferably selected from the group consisting of H and CH3;

[0160] R42' and R43' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0161] In particular, said polymer PI comprises residues of a monomer M1” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) or a mixture thereof.

[0162] in which

[0163] R6, R7 and R8 are independently of each other selected from the group consisting of H, CO2H and CrC3 alkyl;

[0164] R10 is, independently for each unit n, selected from the group consisting of in -NHC(CH3)2CH2C(O)CH3 and -OR5' with R5' selected from the group consisting of H and C1-C18 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0165] R9' is selected from the group consisting of C1-C5 alkyl and C6-C12 substituted aryl by one or more CO2H functional groups;

[0166] X2 is selected from the group consisting of -[-C(O)OC(R16')(R17')C(R18')(R19')-] wl- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 5;

[0167] R16', R17', R18', R19' are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C3 alkyl;

[0168] p' is 0 or 1;

[0169] R11, R12 and R13 are independently of each other selected from the group consisting of H and C1-C3 alkyl;

[0170] R14 is CrC3 alkyl;

[0171] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R 37', R38', R39', R40' and R41' are independently selected from the group consisting of H and CH3;

[0172] R42' and R43' are, independently of each other and independently for each unit n, selected from the group consisting of H and Ci-Cio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0173] More particularly, said monomer M1” may be selected from the group consisting of acrylic acid, 2-carboxyethyl acrylate, methacrylic acid, maleic acid, maleic anhydride, methacrylic anhydride, tetrahydrophthalic anhydride, fumaric acid, crotonic acid, itaconic acid, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-dodecyl acrylate, amyl acrylate, isoamyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, diacetone acrylamide, lauryl acrylate, n-octyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-dodecyl methacrylate, amyl methacrylate, isoamyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, n-octyl methacrylate,ureido methacrylate, acrylonitrile, N-methylol acrylamide, acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, ethylene glycol methacrylate phosphate and mixtures thereof. ,

[0174] Segment SI

[0175] As mentioned above, said PI polymer also comprises one or more SI segments. Said SI segment is selected from formulas (Ia), (Ib), (Ic), (Id), (Ic), (If) and (Ig) or a mixture thereof.

[0176] -P(O)(OX)-[CR1R2CR3((X1)pC(O)R4)-(P(O)(OX))r]n- (la)

[0177]

[0178] -P(O)(OX)-[CR'R2CR3 (OC(O)R4 )-(P(O)(OX))r]n- (Ib) -P(O)(OX)-[CR20R21CR22C(O)OC(O)CR23CR24R25-(P(O)(OX))r]n- (the) -(0XOX.jp- R\ | —tîWOxncH- 7 y ï 0 i (THE)

[0179] -P(O)(OX)-[CR36R37CR38(CN)-(P(O)(OX))r]n- (If)

[0180] -P(O)(OX)-[CR39R40CR41(C(O)NR42R43)-(P(O)(OX))r]n- (Ig)

[0181] in which

[0182] R1, R2, R3 are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, C1-C5 alkyl;

[0183] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl;

[0184] R4' is C1-C5 alkyl;

[0185] n is an integer between 1 and 50000, advantageously between 2 and 40000, preferably between 3 and 30000, more preferably between 4 and 20000, in particular between 5 and 10000, more particularly between 5 and 5000, preferably between 5 and 3000;

[0186] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0187] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16, R17, R18, R19 are independently of each other and independently for each unit w selected from the group consisting of H and C1-C5 alkyl;

[0188] R4 is, independently for each n unit, selected from the group consisting of -NHC(CH3)2CH2C(O)CH3 and -OR5 with R5 selected from the group consisting of H and CrCi8 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five or six membered heterocycle comprising at least one atom nitrogen in its cyclic chain;

[0189] R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups;

[0190] r is, independently for each unit n, 0 or 1;

[0191] p, independently for each unit n, is 0 or 1;

[0192] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0193] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrCio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0194] Said heterocycle may be saturated or unsaturated or aromatic. Said heterocycle may be monocyclic or bicyclic. Said heterocycle may be a pyrrole, pyr-rolidine, pyridine, piperidine, pyrimidine, pyrazine, 1,4-dihydropyridine, indole, oxindole, isatin, quinoline, isoquinoline, quinazoline, imidazoline, pyrazolidine, 2-pyrrolidone, deltalactam, succinimide, 2-imidazolidinone, 4-imidazolidinone ring. Said heterocycle may be substituted by one or more C1-C5 alkyl groups. As mentioned above, the C1-C18 alkyl is optionally substituted by said heterocycle. The latter may be linked to the alkyl chain by the nitrogen atom or any other atom forming the heterocycle. Preferably the heterocycle is 2-pyrrolidone, deltalactam, succinimide, 2-imidazolidinone, 4-imidazolidinone.

[0195] Advantageously, n can be an integer between 1 and 5000 or between 1 and 4000 or between 1 and 3000 or between 1 and 2000 or between 1 and 1000 or between 1 and 500 or between 1 and 400 or between 1 and 300 or between 1 and 200 or between 1 and 100 or between 1 and 50. Preferably, n can be an integer between 2 and 50000 or between 2 and 40000 or between 2 and 30000 or between 2 and 20000 or between 2 and 10000 or between 2 and 5000 or between 2 and 4000 or between 2 and 3000 or between 2 and 2000 or between 2 and 10000 or between 2 and 5000 or between 2 and 4000 or between 2 and 3000 or between 2 and 2000 or between 2 and 1000 or between 2 and 500 or between 2 and 400 or between 2 and 300 or between 2 and 200 or between 2 and 100 or between 2 and 50. More preferably, n can be an integer between 3 and 50000 or between 3 and 40000 or between 3 and 30000 or between 3 and 20000 or between 3 and 10000 or between 3 and 5000 or between 3 and 4000 or between 3 and 3000 or between 3 and 2000 or between 3 and 1000 or between 3 and 50.In particular, n can be an integer between 4 and 50000 or between 4 and 40000 or between 4 and 30000 or between 4 and 20000 or between 4 and 10000 or between 4 and 5000 or between 4 and 4000 or between 4 and 3000 or between 4 and 2000 or between 4 and 1000 or between 4 and 500 or between 4 and 400 or between 4 and 300 or between 4 and 200 or between 4 and 100 or between 4 and 50. More particularly, n can be an integer between 5 and . 50000 or between 5 and 40000 or between 5 and 30000 or between 5 and 20000 or between 5 and 10000 or between 5 and 5000 or between 5 and 4000 or between 5 and 3000 or between 5 and 2000 or between 5 and 1000 or between 5 and 500 or between 5 and 400 or between 5 and 300 or between 5 and 200 or between 5 and 100 or between 5 and 50.

[0196] Advantageously, R1, R2, R3 are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, Ci-C3 alkyl; preferably, R1, R2, R3 are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2 H, CH3.

[0197] Advantageously, R1', R2', R3' are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, CrC3 alkyl; preferably, R1, R2, R3 are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2 H, CH3.

[0198] Advantageously, R4' is C1-C3 alkyl.

[0199] Advantageously, X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); preferably, X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s).

[0200] As mentioned above, w is an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5.

[0201] Advantageously, R16, R17, R18, R19 are independently of each other and independently for each unit w selected from the group consisting of H and CrC 3 alkyl; preferably, R16, R17, R18, R19 are independently of each other and independently for each unit w selected from the group consisting of H and CH3.

[0202] Advantageously, R4 is, independently for each unit n, selected from the group consisting of -NHC(CH3)2CH2C(O)CH3 and -OR5 with R5 selected from the group consisting of H and CrCi8 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R9 is selected from the group consisting of C1-C5 alkyl and C6-Ci2 aryl substituted by one or more CO2H functional groups. Preferably, R4 is, independently for each unit n, -OR5 with R5 selected from the group consisting of H and C1-Ci8 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups. More preferably, R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups.In particular, R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9; R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted by one or more CO2H functional groups. More particularly, R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C8 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9; R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO 2H functional groups.Preferably, R4 is, independently for each n unit, -OR5 with R 5 selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO 2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9; R9 is selected from the group consisting of C1-C5 alkyl and C6-Ci2 aryl substituted by one or more CO2H functional groups. Advantageously, R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and CrC 5 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9; R9 is selected from the group consisting of CrC3 alkyl and C6 aryl substituted with one or more CO2H functional groups.Preferably, R4 is, independently for each unit n, -OR5 with R5 selected from the group consisting of H and C1-C3 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9; R9 is selected from the group consisting of C1-C3 alkyl and C6 aryl substituted by one or more CO2H functional groups.

[0203] Advantageously, R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrC 3 alkyl. Preferably R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R 34, R35, R36, R37, R38, R39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and CH3.

[0204] Advantageously, R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrC 8 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO 3H, -OPO32, -C(O)OR9, -OC(O)R9. Preferably, R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0205] According to a preferred embodiment, said one or more segment(s) SI is selected from formulas (la), (Ib), (le), (Id), (le), (If) and (Ig) as defined above or a mixture thereof; in which

[0206] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, C1-C3 alkyl;

[0207] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl;

[0208] R4' is C1-C3 alkyl;

[0209] n is an integer between 1 and 5000, advantageously between 2 and 4000, preferably between 3 and 3000, more preferably between 4 and 2000, in particular between 5 and 1000, more particularly between 5 and 500;

[0210] R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C18 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9 and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0211] R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups;

[0212] r is, independently for each unit n, 0 or 1;

[0213] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0214] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16, R17, R18, R19 are independently of each other, independently for each unit w selected from the group consisting of H and C1-C3 alkyl;

[0215] p, independently for each unit n, is 0 or 1;

[0216] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0217] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrCio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0218] According to a preferred embodiment, said one or more segment(s) SI is selected from formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) as defined above or a mixture thereof; in which

[0219] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, C1-C3 alkyl;

[0220] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl;

[0221] R4' is CrC3 alkyl;

[0222] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50;

[0223] R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9 and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0224] R9 is selected from the group consisting of CrC3 alkyl and C6-Ci2 aryl substituted with one or more CO2H functional groups;

[0225] r is, independently for each unit n, 0 or 1;

[0226] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0227] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a CrC3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 10; R16, R17, R18, R19 are H;

[0228] p, independently for each unit n, is 0 or 1;

[0229] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0230] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and Ci-Cio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0231] Preferably, said one or more segment(s) SI is selected from formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) as defined above or a mixture thereof; in which

[0232] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, CrC3 alkyl;

[0233] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and CrC3 alkyl;

[0234] R4' is CrC3 alkyl;

[0235] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50;

[0236] R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9;

[0237] R9 is selected from the group consisting of CrC3 alkyl and C6 arylc substituted with one or more CO2H functional groups;

[0238] r is, independently for each unit n, 0 or 1;

[0239] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0240] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a CrC3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 10; R16, R17, R18, R19 are H;

[0241] p, independently for each unit n, is 0 or 1;

[0242] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl, preferably selected from the group consisting of H and CH3;

[0243] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C8 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, - OC(O)R9.

[0244] More preferably, said one or more segment(s) SI is selected from formulas (la), (Ib), (le), (Id), (le), (If), (Ig) and (Ih) as defined above or a mixture thereof; in which

[0245] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, C1-C3 alkyl;

[0246] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl;

[0247] R4' is CrC3 alkyl;

[0248] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50;

[0249] R4 is, independently for each unit n, -OR5 with R5 selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9;

[0250] R9 is selected from the group consisting of C1-C3 alkyl and C6aryl substituted with one or more CO2H functional groups;

[0251] r is, independently for each unit n, 0 or 1;

[0252] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0253] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a CrC3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 10; R16, R17, R18, R19 are H;

[0254] p, independently for each unit n, is 0 or 1;

[0255] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each n unit, selected from the group consisting of H and CrC3 alkyl, preferably selected from the group consisting of H and CH3;

[0256] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and CrC8 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0257] In particular, said one or more segment(s) SI is selected from formulas (la), (Ib), (le), (Id), (le), (If), (Ig) and (Ih) as defined above or a mixture thereof; in which

[0258] R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2H, CH3;

[0259] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and CH3;

[0260] R4' is CrC3 alkyl;

[0261] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50;

[0262] R4 is, independently for each unit n, -OR5 with R5 selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9;

[0263] R9 is selected from the group consisting of CrC3 alkyl and C6 arylc substituted with one or more CO2H functional groups;

[0264] r is, independently for each unit n, 0 or 1;

[0265] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0266] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 5; R16, R17, R18, R19 are H;

[0267] p, independently for each unit n, is 0 or 1;

[0268] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and CH3;

[0269] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0270] More particularly, said one or more segment(s) SI is selected from formulas (la), (Ib), (le), (Id), (le), (If), (Ig) and (Ih) as defined above or a mixture thereof; in which

[0271] R1 and R2 are, independently of each other and independently for each unit n, H or CO2H; R3 is, independently for each unit n, H or CH3;

[0272] R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and CH3;

[0273] R4' is CrC3 alkyl;

[0274] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particu- mainly between 5 and 50;

[0275] R4 is, independently for each unit n, -OR5 with R5 selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9;

[0276] R9 is selected from the group consisting of CrC3 alkyl and C6 arylc substituted with one or more CO2H functional groups;

[0277] r is, independently for each unit n, 0 or 1;

[0278] X is, independently for each unit n, selected from the group consisting of H, Na, K and Li;

[0279] X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a CrC3 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 5; R16, R17, R18, R19 are H;

[0280] p, independently for each unit n, is 0 or 1;

[0281] R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, R38, R 39, R40 and R41 are H;

[0282] R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

[0283] According to a preferred embodiment, said one or more segment(s) SI is selected from the group consisting of:

[0284] -P(O)(OX)-[CH(CO2H)CH(CO2H)-(P(O)(OX))r]n-,

[0285] -P(O)(OX)-[CH2CH(CO2H)-(P(O)(OX))r]n-,

[0286] -P(O)(OX)-[CH2C(CH3)(CO2H)-(P(O)(OX))r]n-,

[0287] -P(O)(OX)-[CH2CH(CO2CH3)-(P(O)(OX))r]n-,

[0288] -P(O)(OX)-[CH2C(CH3)(CO2CH3)-(P(O)(OX))r]n-,

[0289] -P(O)(OX)-[CH2CH(CO2CH2CH2OH)-(P(O)(OX))r]n-,

[0290] -P(O)(OX)-[CH2CH(CO2CH2CH(OH)CH3)-(P(O)(OX))r]n-,

[0291] -P(O)(OX)-[CH2CH(CO2CH(CH3)CH2(OH))-(P(O)(OX))r]n-,

[0292] -P(O)(OX)-[CH2CH(CO2CH2CH2CO2H)-(P(O)(OX))r]n-,

[0293] -P(O)(OX)-[CH2CH(CO2CH2CH2-O-C(O)-CH2CH2CO2H)-(P(O)(OX))r]n-,

[0294] -P(O)(OX)-[CH2CH(CO2CH2CH2-O-C(O)-C6H4CO2H)-(P(O)(OX))r]n-,

[0295] -P(O)(OX)-[CH2CH(CO2CH2CH2CH2CH(CO2H)CH2CH2CO2H)-(P(O)(OX))r]n-,

[0296] -P(O)(OX)-[CH2C(CH3)(CO2CH2CH3)-(P(O)(OX))r]n-,

[0297] -P(O)(OX)-[CH2C(CH3)(CO2CH2CH2CH3)-(P(O)(OX))r]n-,

[0298] -P(O)(OX)-[CH2C(CH3)(CO2CH(CH3)2)-(P(O)(OX))r]n-,

[0299] -P(O)(OX)-[CH2C(CH3)(CO2C4H9)-(P(O)(OX))r]n-,

[0300] -P(O)(OX)-[CH2C(CH3)(CO2C5Hn)-(P(O)(OX))r]n-,

[0301] -P(O)(OX)-[CH2CH(CO2CH2CH3)-(P(O)(OX))r]n-,

[0302] -P(O)(OX)-[CH2CH(CO2CH2CH2CH3)-(P(O)(OX))r]n-,

[0303] -P(O)(OX)-[CH2CH(CO2CH(CH3)2)-(P(O)(OX))r]n-,

[0304] -P(O)(OX)-[CH2CH(CO2C4H9)-(P(O)(OX))r]n-,

[0305] -P(O)(OX)-[CH2CH(CO2C5Hn)-(P(O)(OX))r]n-,

[0306] -P(O)(OX)-[CH(CH3)CH(CO2H)-(P(O)(OX))r]n-,

[0307] -P(O)(OX)-[CH2C(CH2CO2H)(CO2H)-(P(O)(OX))r]n-,

[0308] -P(O)(OX)-[CH2CH((CO2CH2CH2)wCO2H)-(P(O)(OX))r]n-,

[0309] -P(O)(OX)-[CH2CH(CN)-(P(O)(OX))r]n-,

[0310] -P(O)(OX)-[CH2CH(C(O)NH2)-(P(O)(OX))r]n-,

[0311] -P(O)(OX)-[CH2C(CH3)(CO2CH2CH2OPO32 )-(P(O)(OX))r]n-,

[0312] -P(O)(OX)-[CH2CH(NHC(CH3)2CH2SO3H)-(P(O)(OX))r]n-,

[0313] -P(O)(OX)-[CH2C(CH3)(CO2C(O)OC(CH3)=CH2)-(P(O)(OX))r]n-, H H i —-Z—- Ox ; )f — I —Ms H H ................y--------Y— / X § H......XHHI / \ / \ * H >----YH s ys \

[0314] -P(O)(OX)-[CH2CH(C(O)NHCH2OH)-(P(O)(OX))r]n-,

[0315] in which

[0316] r is, independently for each unit n, 0 or 1;

[0317] X is, independently for each unit n, selected from the group consisting of in H, Na, K and Li;

[0318] n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50.

[0319] Said polymer PI thus comprises residues of said fluorinated monomer Ml and one or more segment(s) SI as described above. Said fluorinated monomer Ml and said one or more segment(s) SI preferably form blocks. Said polymer PI may have a block structure of formula ABA or AB with A a block comprising residues of said fluorinated monomer Ml and B being formed by an SI segment. Said SI segment can be covalently linked to at least one of the residues of said fluorinated monomer Ml via a functional group -P(O)(OX) of said SI segment.

[0320] If said polymer PI comprises residues Ml' and Ml”, these are preferably randomly distributed within said polymer PI. Thus, said segment SI may also be covalently linked to at least one residue of said monomer Ml' or Ml” via a functional group -P(O)(OX) thereof with X as defined in the present application.

[0321] The presence of a covalent bond between said segment SI and one of the residues Ml, Ml' or Ml” can be determined by 19F or 31P NMR in a suitable solvent for dissolving the polymer PI, such as for example DMSO d6. Preparation process

[0322] Said polymer PI is prepared by a polymerization process in a reactor between at least one monomer and a compound from which said segment SI is derived.

[0323] Thus, said process for preparing said polymer PI comprises a step of polymerization in aqueous medium of said fluorinated monomer Ml as defined in the present invention in the presence of a compound SI' comprising one or more segment(s) SI as defined in the present application.

[0324] The process for preparing said PI polymer may be an emulsion or suspension process. The polymerization step may be carried out at a temperature above 40°C, preferably at a temperature of 40°C to 120°C, in particular of 40°C to 90°C. The polymerization step may be carried out at a pressure of 10 to 120 bara, advantageously at a pressure of 15 bara to 110 bara, preferably at a pressure of 20 bara to 100 bara.

[0325] The process for preparing said PI polymer is carried out in the presence of an initiator. The initiator may be one or a combination of several of the initiators known in the art to be useful in the dispersion polymerization of halogenated monomers. Suitable non-limiting classes of initiators include persulfate salts, peroxides and redox systems. Examples of persulfate salts are sodium persulfate, potassium persulfate or ammonium persulfate. The amount of persulfate salt added to the reaction mixture based on the total weight of monomer added to the reaction mixture is typically from about 0.005 to about 1.0 wt%. Organic peroxides that are useful include dialkyl peroxides, alkyl hydroperoxides, peroxyesters and peroxydicarbonates. A suitable example of dialkyl peroxide is di-tert-butyl peroxide.Examples of suitable peroxy esters include tert-amyl peroxypivalate, tert-butyl peroxypivalate and succinic acid peroxide. Examples of suitable peroxydicarbonate initiators include peroxydi- . di-n-propyl carbonate and diisopropyl peroxydicarbonate, which are typically added to the reaction mixture in an amount based on the total weight of monomer added to the reaction mixture of about 0.05 to about 2.5% by weight.

[0326] The initiator may comprise a redox system. By "redox system" is meant a system comprising an oxidizing agent, a reducing agent, and optionally a promoter acting as an electron transfer medium. The promoter is a component which, in different oxidation states, is capable of reacting with both the oxidizing agent and the reducing agent, thereby accelerating the overall reaction. Oxidizing agents include, for example, persulfate salts; peroxides, such as hydrogen peroxide; hydroperoxides, such as tert-butyl hydroperoxide and cumene hydroperoxide; and oxidizing metal salts such as, for example, ferric sulfate and potassium permanganate. Examples of reducing agents include sodium formaldehyde sulfoxylate; sodium or potassium sulfite, bisulfite, or meta-bisulfite; ascorbic acid; oxalic acid; and reduced metal salts.Typical promoters include transition metal salts such as ferrous sulfate. In redox systems, the oxidizing agent and reducing agent are typically used in an amount of about 0.01 to about 0.5 weight percent based on the total weight of monomer added to the reaction mixture. The promoter, if used, is typically employed in an amount of about 0.005 to about 0.025 weight percent based on the total weight of monomer added to the reaction mixture.

[0327] A paraffin antifoulant is optionally used in the polymerization. Any long-chain saturated hydrocarbon wax or oil may be used. The oil or wax is added to the reactor prior to fluoropolymer formation in an amount sufficient to minimize polymer adhesion to the reactor components. This amount is generally proportional to the interior surface area of ​​the reactor and may vary from about 1 to about 40 mg / cm2 of interior surface area of ​​the reactor. If a paraffin wax or hydrocarbon oil is used as the antifoulant, the amount used is generally about 5 mg / cm2 of interior surface area of ​​the reactor.

[0328] The polymerization reaction mixture may optionally contain a buffering agent to maintain a controlled pH during the polymerization reaction. The pH is generally controlled in the range of 3 to 8. The buffering agent may be added at the beginning, at different points or throughout the polymerization. Suitable exemplary buffering agents are phosphate buffers and acetate buffers, which are well known to those skilled in the art.

[0329] Molecular weight regulators, also called chain transfer agents, may optionally be used to adjust the molecular weight profile of the product. They may be added in a single portion at the beginning of the reaction, pro gradually or continuously throughout the reaction. The amount of molecular weight regulator added to the polymerization reaction is generally from about 0.05 to about 5% by weight, more generally from about 0.1 to about 2% by weight based on the total weight of monomer added to the reaction mixture. Oxygenated compounds such as alcohols, carbonates, ketones, esters, and ethers can serve as molecular weight regulators. Examples of suitable oxygenated compounds include isopropyl alcohol, acetone, ethyl acetate, and diethyl carbonate. Other classes of molecular weight regulators include halogenated compounds such as chlorocarbons, hydrochlorocarbons, hydrofluorocarbons, chlorofluorocarbons, and hydrochlorofluorocarbons.Particular examples of halogenated molecular weight regulators include 1-fluoroethane, trichlorofluoromethane, and 1,1-dichloro-2,2,2-trifluoroethane. Certain hydrocarbons can be used as molecular weight regulators, such as hydrocarbons that contain two to five carbon atoms, with ethane and propane as particular examples.

[0330] The polymerization step of the present process may optionally be carried out in the presence of a surfactant. For example, said surfactant comprises a polyethylene glycol segment and a polypropylene glycol segment. Preferably, said surfactant has an HLB value of 1 to 20, in particular an HLB value of 1 to 5 or 10 to 15. In particular, said surfactant comprising a polyethylene glycol segment and a polypropylene glycol segment, has an HLB value of 1 to 5 and a weight average molecular weight of 2500 to 10000 g.mol-1. Alternatively, said surfactant comprising a polyethylene glycol segment and a polypropylene glycol segment, has an HLB value of 10 to 15 and a weight average molecular weight of 500 to 2500 g.mol-1. The surfactant is preferably used when the polymerization is carried out in emulsion.

[0331] The polymerization step of the present process may optionally be carried out in the presence of a dispersant. This is preferably used when the polymerization is carried out in suspension. The dispersant may be polyvinyl alcohol (PVA) or a compound comprising a cellulose unit such as methylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose.

[0332] The polymerization step a) may also comprise the addition of one or more monomers Ml' or Ml” as defined in the present application. The monomers Ml' and Ml” may be added before the initiation of the polymerization reaction and / or after the latter.

[0333] The monomers Ml, Ml', Ml” and the compound SI' may be added continuously or discontinuously during the polymerization step. The term continuous encompasses addition by multiple additions throughout the production process. The term discontinuous includes the addition only once at the beginning of the process or during it in a single addition.

[0334] According to a preferred embodiment, said compound SI' comprising one or more segment(s) SI as defined in the present application and at least one, preferably two, HP(O)(OX)- group(s) at the end of the chain. Preferably, said compound SI' is obtained by reaction between an aqueous solution comprising a hypophosphite salt [H2P(O)(OX)]xMy+ and one or more monomer(s) Ml” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) as defined in the present application, or a mixture thereof. In the formula of the hypophosphite salt [H2P(O)(OX)]xMy+ M is H, an alkali or alkaline earth metal; and x and y are 1 if M is H or an alkali metal or x and y are 2 if M is an alkaline earth metal. Preferably, said hypophosphite salt is sodium hypophosphite, lithium hypophosphite, potassium hypophosphite or calcium hypophosphite or may be hypophosphorous acid.In particular, said hypophosphite salt is sodium hypophosphite; preferably in the monohydrate form. The compound SI' may have a molecular mass greater than 500 g / mol, advantageously greater than 1000 g / mol, preferably greater than 1500 g / mol, measured according to the aqueous GPC analysis method described below. Advantageously, the compound SI' may have a molecular mass less than 100000 g / mol, advantageously greater than 50000 g / mol, preferably greater than 10000 g / mol, measured according to the aqueous GPC analysis method described below.

[0335] Said reaction is carried out at a temperature of 50°C to 150°C, advantageously of 75°C to 150°C, preferably of 75°C to 125°C, in particular of 90°C to 110°C. The reaction is also carried out in the presence of an initiator. The choice of the initiator is not limited. It may be a peroxodisulfate salt or a persulfate salt or an organic peroxide. The mass content of initiator is of 0.5% to 10%, preferably of 0.5% to 5% based on the total weight of monomer M1” used in the reaction.

[0336] According to a particular embodiment, said PI polymer preferably has a melting temperature of less than 175°C, advantageously less than 170°C measured according to the ASTM D3418 standard. Preferably, said PI polymer has a melting temperature of 140°C to 175°C, preferably of 150°C to 170°C measured according to the ASTM D3418 standard. According to a particular embodiment, said PI polymer preferably has a crystallization temperature of 120°C to 150°C, preferably of 125°C to 140°C measured according to the ASTM D3418 standard. According to a particular embodiment, said PI polymer has a crystallinity rate of 40% to 50%. The degree of crystallinity can be determined by comparing the reference enthalpy (104.7 J / g) with the enthalpy measured for melting during two heatings (according to ASTM D3418). Composition

[0337] As mentioned above, said composition may comprise, in addition to polymer PI, a fluoropolymer P2 or a hydrophilic polymer P3 as described below. When said composition comprises a blend between said polymer PI and said fluoropolymer P2, P3 or both, said composition preferably comprises at least 1% by weight of said polymer PI, advantageously at least 5% by weight of said polymer PI, preferably at least 10% by weight of said polymer PI, more preferably at least 20% by weight of said polymer PI, in particular at least 30% by weight of said polymer PI, more particularly at least 40% by weight of said polymer PI, preferably at least 50% by weight of said polymer PI based on the total weight of said polymers PI, P2 and P3 therein.

[0338] According to a preferred embodiment, said fluoropolymer P2 comprises residues of a monomer M2 selected from the group consisting of vinylidene fluoride, vinyl fluoride; trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2 CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3 H; a monomer of formula CF2=CFOCF2CF2SO2F; a monomer of formula F(CF2)n CH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2 OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof.

[0339] According to one embodiment, the fluorinated polymer P2 is a homopolymer of vinylidene fluoride.

[0340] According to another embodiment, the fluoropolymer P2 is a copolymer of vinylidene fluoride with at least one monomer compatible with vinylidene fluoride. The comonomers compatible with vinylidene fluoride may be halogenated (fluorinated, chlorinated or brominated) or non-halogenated. Examples of suitable fluorinated comonomers are vinyl fluoride; trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(l,3-dioxole); perfluoro(2,2-dimethyl-l,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2CF2SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2 )p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-1-propene or a mixture thereof. The fluorinated comonomer may contain a chlorine or bromine atom.It may in particular be chosen from bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoroethylene and chlorotrifluoropropene. Chlorofluoroethylene may denote either 1-chloro-1-fluoroethylene or 1-chloro-2-fluoroethylene. The 1-chloro-1-fluoroethylene isomer is preferred. Chlorotrifluoropropene is preferably 1-chloro-3,3,3-trifluoropropene or 2-chloro-3,3,3-trifluoropropene. The VDF copolymer may also comprise non-halogenated monomers such as ethylene, and / or acrylic or methacrylic comonomers.

[0341] The fluoropolymer P2 preferably contains at least 50 mol% vinylidene fluoride, advantageously at least 60 mol% vinylidene fluoride, preferably at least 70 mol% vinylidene fluoride. The comonomer may be present in a content of 1 to 50%, advantageously 2 to 30% by weight relative to the weight of said fluoropolymer P2.

[0342] According to one embodiment, the fluoropolymer P2 is a copolymer of vinylidene fluoride (VDF) and hexafluoropropylene (HFP) (P(VDF-HFP)), having a percentage by weight of hexafluoropropylene monomer units of 2 to 30%, advantageously of 2 to 25%, preferably of 2 to 20%, preferably of 4 to 15% by weight relative to the weight of said fluoropolymer P2. According to another embodiment, the fluoropolymer P2 is a copolymer of vinylidene fluoride (VDF) and hexafluoropropylene (HFP) (P(VDF-HFP)), having a percentage by weight of hexafluoropropylene monomer units of 10 to 30%, advantageously of 10 to 25% by weight relative to the weight of said fluoropolymer P2.

[0343] According to one embodiment, the fluorinated polymer P2 is a copolymer of vinylidene fluoride and tetrafluoroethylene (TFE).

[0344] According to one embodiment, the fluorinated polymer P2 is a copolymer of vinylidene fluoride and chlorotrifluoroethylene (CTFE).

[0345] According to one embodiment, the fluorinated polymer P2 is a terpolymer of VDF- TFE-HFP. According to one embodiment, the fluoropolymer P2 is a VDF-TrFE-TFE terpolymer (TrFE being trifluoroethylene). In these terpolymers, the mass content of VDF is at least 10%, the comonomers being present in variable proportions.

[0346] According to one embodiment, the fluoropolymer P2 comprises monomeric units carrying at least one of the following functions: carboxylic acid, carboxylic acid anhydride, carboxylic acid esters, epoxy groups (such as glycidyl), amide, hydroxyl, carbonyl, mercapto, sulfide, oxazoline, phenolic, ester, ether, siloxane, sulfonic, sulfuric, phosphoric, phosphonic. The function is introduced by a chemical reaction which may be grafting, or a copolymerization of the vinylidene fluoride (VDF) monomer with a monomer carrying at least one of said functional groups and a vinyl function capable of copolymerizing with the VDF monomer, according to techniques well known to those skilled in the art.

[0347] According to one embodiment, the functional group carries a carboxylic function (acid, ester or anhydride) such as for example acrylic acid, methacrylic acid, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, 2-carboxyethyl acrylate, acryloyloxy propylsuccinate and hydroxyethylhexyl(meth)acrylate. Thus, said fluoropolymer P2 may comprise residues of a monomer selected from the group consisting of acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxyethylhexyl methacrylate, 2-carboxyethyl acrylate and acryloyloxy propylsuccinate. According to one embodiment, the units carrying the carboxylic function further comprise a heteroatom chosen from oxygen, sulfur, nitrogen and phosphorus. Preferably, the content of monomer M2 in said fluoropolymer P2 is from 0.01% to 5 mol%.In this embodiment, at least 40% of the units derived from the monomer M2' are distributed between two vinylidene fluoride units.

[0348] According to one embodiment, the functionality is introduced via the transfer agent used during the synthesis process. The transfer agent is a polymer with a molar mass of less than or equal to 20,000 g / mol and carrying functional groups chosen from the groups: carboxylic acid, carboxylic acid anhydride, carboxylic acid esters, epoxy groups (such as glycidyl), amide, hydroxyl, carbonyl, mercapto, sulfide, oxazoline, phenolic, ester, ether, siloxane, sulfonic, sulfuric, phosphoric, phosphonic. An example of a transfer agent of this type is acrylic acid oligomers. The content of functional groups in said fluoropolymer P2 is at least 0.01 mol%, preferably at least 0.1 mol%, and at most 15 mol%, preferably at most 10 mol%.

[0349] Alternatively, the functional group may be introduced by an oligomeric or polymeric compound comprising said functional group and mixed with the polymer P2. The oligomeric or polymeric compound may be impregnated in or mixed with the polymer P2 or intimately mixed therewith. In this case, the functional group may be derived from a (meth)acrylic acid compound selected from acrylic acid, methacrylic acid, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, hydroxyethylhexyl(meth)acrylate, 2-carboxyethyl acrylate and acryloyloxy propylsuccinate. For example, the functional group may be an oligomer or a polymer comprising monomeric units derived from a monomer selected from the group consisting of acrylic acid, methacrylic acid, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, hydroxyethylhexyl(meth)acrylate and acryloyloxy propylsuccinate.According to one embodiment, said oligomer or polymer has a weight-average molecular mass less than or equal to 100,000 g / mol, advantageously less than 80,000 g / mol, preferably less than 60,000 g / mol, more preferably less than 40,000 g / mol, in particular less than 20,000 g / mol.

[0350] The fluoropolymer P2 preferably has a melt viscosity greater than 10 Pa.s, advantageously greater than 50 Pa.s, preferably greater than 100 Pa.s, more preferably greater than 500 Pa.s, in particular greater than 1000 Pa.s, according to the ASTM D-3835 method measured at 232°C and 100 sec-1.

[0351] According to one embodiment, the fluoropolymer P2 bearing functional groups can crosslink either by self-condensation of its functional groups, or by reaction with a catalyst and / or a crosslinking agent, such as melamine resins, epoxy resins and the like, as well as known crosslinking agents of low molecular weight such as di- or higher polyisocyanates, polyaziridines, polycarbodiimides, polyoxazolines, dialdehydes such as glyoxal, acetoacetates, malonates, acetals, di- and tri-functional thiols and acrylates, cycloaliphatic epoxy molecules, organosilanes such as epoxysilanes and amino silanes, carbamates, diamines and triamines, inorganic chelating agents such as certain zinc and zirconium salts, titaniums, glycourils and others aminoplasts.In some cases, functional groups from other polymerization ingredients, such as surfactants, initiators, seed particles, may be involved in the crosslinking reaction. When two or more functional groups are involved in the crosslinking process, the complementary reactive group pairs are, for example, hydroxyl-isocyanate, acid-epoxy, amine-epoxy, hydroxyl-melamine, acetoacetate-acid. Acrylate and / or methacrylate monomers not containing functional groups capable of entering into crosslinking reactions after poly . merization, must preferably represent 70% or more by weight of the total monomer mixture, and more preferably, must be greater than 90% by weight. According to one embodiment, the fluoropolymer P2 comprises a crosslinking agent selected from the group consisting of isocyanates, diamines, adipic acid, dihydrazides and combinations thereof.

[0352] According to another embodiment, said composition may comprise a polymer P3. As mentioned above, said hydrophilic polymer P3 comprises residues of a monomer M3 of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) as defined in the present application or a mixture thereof. Said hydrophilic polymer P3 may also comprise a monomer derived from:

[0353] - (A) an alkenyl compound containing a functional group, and

[0354] - (B) an alkenyl compound without a functional group.

[0355] The alkenyl compound (A) containing a functional group includes vinyl ester compounds such as vinyl acetate, vinyl neodecanoate and the like; amide compounds such as N-methylacrylamide, N-methylmethacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-alkylacrylamide, N-alkylmethacrylamide, N,N-dialkylacrylamide, N,N-dialkylmethacrylamide, diacetone acrylamide and the like; acrylic acid esters such as N-dialkylaminoethyl acrylate, glycidyl acrylate, n-dodecyl acrylate, fluoroalkyl acrylate and the like; methacrylic acid esters such as dialkylaminoethyl methacrylate, fluoroalkyl methacrylate, glycidyl methacrylate, ethylene glycol dimethacrylate and the like; and alkenyl glycidyl ether compounds such as allyl glycidyl ether and the like.Of these, N-methylolacrylamide, N-methylolmethacrylamide, diacetone acrylamide, and allyl glycidyl ether are preferred. These compounds may be used alone or as a mixture of two or more.

[0356] The functional group-free alkenyl compound (B) includes, for example, conjugated dienes such as 1,3-butadiene, isoprene and the like; divinyl hydrocarbon compounds such as divinyl benzene and the like; and alkenyl cyanides such as acrylonitrile, methacrylonitrile and the like. These compounds may be used alone or as a mixture of two or more.

[0357] It is preferable that the functional alkenyl compound (A) is used in a proportion of less than 50% by weight relative to the weight of the monomer mixture and that the functional group-free alkenyl compound (B) is used in a proportion of less than 30% by weight relative to the weight of the monomer mixture.

[0358] According to certain embodiments, the polymers P1, P2 and P3 are bio-sourced. The term "bio-sourced" means "derived from biomass". This makes it possible to improve the ecological footprint of the separator. The bio-sourced vinylidene fluoride can be ca characterized by a renewable carbon content, i.e. carbon of natural origin and originating from a biomaterial or biomass, of at least 1 atomic % as determined by the 14C content according to standard NF EN 16640. The term "renewable carbon" indicates that the carbon is of natural origin and originates from a biomaterial (or biomass), as indicated below. According to certain embodiments, the bio-carbon content may be greater than 5%, preferably greater than 10%, preferably greater than 25%, preferably greater than or equal to 33%, preferably greater than 50%, preferably greater than or equal to 66%, preferably greater than 75%, preferably greater than 90%, preferably greater than 95%, preferably greater than 98%, preferably greater than 99%, advantageously equal to 100%.

[0359] The polymers P2 and P3 used in the invention can be obtained by known polymerization methods such as emulsion or suspension polymerization. According to one embodiment, they are prepared by an emulsion polymerization process in the absence of fluorinated surfactant.

[0360] Said polymers PI and P2 may be in the form of a latex generally having a solids content of 10 to 60% by weight, preferably 10 to 50%, and having a weight average particle size of less than 1 micrometer, preferably less than 1000 nm, preferably less than 800 nm, and more preferably less than 600 nm. The weight average particle size is generally at least 20 nm, preferably at least 50 nm, and advantageously the average size is in the range of 100 to 400 nm. The polymer particles may form agglomerates having a weight average size of 1 to 30 micrometers, and preferably 2 to 20 micrometers. The agglomerates may break into discrete particles during formulation and application to a substrate.

[0361] According to a particular embodiment, said composition comprises said polymer PI and said polymer P2. As mentioned above, in this composition, the mass content of polymer PI is at least 1%, advantageously at least 5%, preferably at least 10%, more preferably at least 20%, in particular at least 30%, more particularly at least 40%, preferably at least 50% based on the total weight of said polymers PI and P2 in said composition.

[0362] According to a particular embodiment, said composition comprises said polymer PI and said polymer P3. As mentioned above, in this composition, the mass content of polymer PI is at least 1%, advantageously at least 5%, preferably at least 10%, more preferably at least 20%, in particular at least 30%, more particularly at least 40%, preferably at least 50% based on the total weight of said polymers PI and P3 in said composition.

[0363] When said composition comprises, in addition to polymer PI, said polymer P2, P3 or a mixture of both, the content of polymer PI is from 1 to 99%, advantageously from 5 to 95%, preferably from 10 to 90% based on the total weight of polymers PI, P2 and P3. Use

[0364] The PI polymer or said composition according to the present application can be used in numerous applications. Thus, they can be used as a binder for an electrode (cathode or anode) or as a coating for a separator.

[0365] The PI polymer or said composition according to the present application can be used as a binder for an electrode. Thus, according to another aspect, the present invention provides an electrode composition comprising said PI polymer or said composition according to the present invention, an active material and optionally a conductive agent.

[0366] In a preferred embodiment, the electrode composition has the following mass composition:

[0367] a. 50% to 99.95% of active material, preferably 50% to 99%,

[0368] b. 25% to 0% conductive agent, preferably 25% to 0.5%,

[0369] c. 25% to 0.05% of said binder according to the invention, preferably 25% to 0.5%,

[0370] d. 0% to 5% of at least one additive selected from the group consisting of a plasticizer, an ionic liquid, a dispersing agent for a conductive additive, and a flow aid;

[0371] the sum of all these percentages being 100%.

[0372] The conductive agents in the electrode are composed of one or more materials that can enhance conductivity. Some examples include carbon blacks such as acetylene black, Ketjen black; carbon fibers, such as carbon nanotube, carbon nanofiber, vapor-grown carbon fiber; metal powders such as SUS powder, and aluminum powder.

[0373] The active materials in the electrode compositions are materials that are capable of storing and releasing lithium ions.

[0374] In a preferred embodiment, said electrode is a negative electrode. In particular, for a negative electrode, said active material is selected from the group consisting of a lithium alloy, lithium metal, a metal oxide, a carbon material such as graphite or hard carbon, silicon, a silicon alloy and Li4TiO12. The shape of the negative electrode active material is not particularly limited but is preferably particulate.

[0375] In another preferred embodiment, said electrode is a positive electrode. Preferably, for a positive electrode, said active material is selected from the group consisting of LiCoO2, Li(Ni, Co, AI)O2, Li(l+ x), NiaMnbCoc (x represents a real number of 0 or more, a = 0.8, 0.6, 0.5, or 1 / 3, b = 0.1, 0.2, 0.3, or 1 / 3, c = 0.1, 0.2, or 1 / 3), LiNiO2, LiMn2O4, LiCoMnO4, Li3NiMn3O3, Li3Fe2(PO4)3, Li3V2(PO4)3, a spinel Li Mn substituted by a different element having a composition represented by Lii+xMn2 x yMyO4, M representing at least one metal selected from Al, Mg, Co, Fe, Ni, and Zn, x and y independently representing a real number between 0 and 2, lithium titanate LixTiOy where x and y independently represent a real number between 0 and 2, and a lithium metal phosphate having a composition represented by LiMPO4, M representing Fe, Mn, Co, or Ni. The shape of the positive electrode active material is not particularly limited but is preferably particulate. In addition, the surface of each of the materials described above can be coated.The coating material is not particularly limited as long as it has lithium ion conductivity and contains a material capable of being maintained as a coating layer on the surface of the active material. Examples of the coating material include LiNbO3, Li4Ti50i2, and Li3PO4. .

[0376] Said electrode composition can be deposited on at least one face of a current collector to form said electrode. This deposition can be carried out in the presence of an organic solvent, water, a mixture of both or by a solvent-free process, i.e. by a dry coated electrode production process. Said organic solvent can be selected from the group consisting of n-methylpyrrolidone (NMP), dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), triethyl-phosphite (TEP), acetone, cyclopentanone, tetrahydrofuran, methyl ethylketone (MEK), methyl isobutyl ketone (MiBK), ethyl acetate (EA), butyl acetate (BA), ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), gamma-butyrolactone and N-butylpyrrolidone; and mixtures thereof.

[0377] According to another aspect of the present invention, a Li-ion battery is provided. Preferably, the Li-ion battery comprises a positive electrode, a negative electrode and a separator, at least one electrode being an electrode according to the present invention.

[0378] According to another aspect of the present invention, said PI polymer or said composition according to the present invention can be used as a coating in a separator arranged between two electrodes. Said separator according to the present invention comprises a coating comprising, preferably consisting of, said PI polymer or said composition according to the present invention, optionally arranged on one or both faces of a porous support. In this case, the coating is used to coat the support of a separator, on at least one face, in the form of a monolayer or multilayers. There is no particular limitation in the choice of the support which is coated with the coating of the invention, as long as it is a porous substrate having pores. When it comprises several layers, the coating as described in the present invention is arranged on the external face of the support, that is to say on the face which will first be in contact with the electrolytic composition used in the battery. Advantageously, the application of the coating on the support is done by aqueous or solvent means. The porous substrate can take the form of a membrane or a fibrous fabric. When the porous substrate is fibrous, it can be a non-woven web forming a porous web, such as a web obtained by direct spinning or melt-blowing (of the "spunbond" or "melt-blown" type) or electro-spinning.Examples of porous substrates useful in the invention as a support include, but are not limited to: polyolefins, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene or mixtures thereof. However, other heat-resistant engineering plastics may be used without particular limitation. Nonwoven materials made of natural and synthetic materials may also be used as the substrate of the separator. The porous substrate generally has a thickness of 1 to 50 μm, and are typically membranes obtained by extrusion and stretching (wet or dry process) or cast nonwovens. The porous substrate preferably has a porosity of between 5% and 95%.The average pore size (diameter) is preferably between 0.001 and 50 pm, more preferably between 0.01 and 10 pm. The support may also be aluminum or aluminum coated with a polymer layer.

[0379] In addition to said composition, the separator coating may contain inorganic particles that serve to form micropores in the coating (the interstices between inorganic particles). The addition of inorganic particles may also contribute to heat resistance or improve wettability. In one embodiment, said coating comprises from 50 to 99 percent by weight of inorganic particles, based on the weight of the coating. These inorganic particles must be electrochemically stable (not subject to oxidation and / or reduction in the range of voltages used). In addition, powdered inorganic materials preferably have high ionic conductivity. Low density materials are preferred over higher density materials, since the weight of the produced battery can be reduced. The dielectric constant is preferably equal to or greater than 5.According to one embodiment, said inorganic particles are chosen from the group consisting of: BaTiO3, Pb(Zr,Ti)O3, Pb 1-x LaxZryO3 (0 <x<l, 0<y<l), PBMg3Nb2 / 3)3,PbTiO3, hafnie (HfO (HfO2), SrTiO3, SnO2, CeO2, MgO, NiO, CaO, ZnO, Y2O3, bohémite (y-AlO(OH)), A12O3, TiO2, SiC, ZrO2, silicate de bore, BaSO4, nano-argiles, ou leurs mélanges. Le revêtement pour séparateur peut éventuellement comprendre de 0 à 15 % en poids sur la base du . polymer, and preferably 0.1 to 10% by weight of additives, chosen from dispersants, thickeners, pH adjusting agents, anti-sedimentation agents, surfactants, wetting agents, fillers, anti-foaming agents and fugitive or non-fugitive adhesion promoters. The fillers mentioned here in the additives are different from the inorganic particles mentioned above.

[0380] According to another aspect of the present invention, a Li-ion battery is provided. Preferably, the Li-ion battery comprises a positive electrode, a negative electrode and said separator according to the present invention. Said battery may also contain an electrolyte. Preferably, said electrolyte comprises an alkali metal salt selected from the group consisting of LiCF3SO3, LiPF6, LiC104, LiBF4, LiB(C2O4)2, LiN(SO2F)2, LiN(SO2CF3)2, LiN(SO2C2F3)2, LiN(SO2C2F5)2, LiN(SO2F)(SO2CF3), LiN(SO2F)(SO2C2F5), LiN(SO2CF3)(SO2C2F5), LiAsF6, LiBF2C2O4, LiNO3, LiPF3(CF2 CF3)3, LiBETI, LiTDI or a mixture thereof.

[0381] According to another aspect of the present invention, said PI polymer or said composition can be used in the preparation of a conductive polymer, a solid electrolyte for fuel cells, a hydrophilic coating, a hydrophobic coating or a UV absorbing coating. Said copolymer can be used as an adhesive for a multilayer structure extruded in the form of a film, a sheet or a tube. Said PI polymer or said composition can also be used as a coating on a metal. Examples

[0382] Aqueous GPC analysis method for the compound SI' from which the segment SI is derived.

[0383] The molecular weight or mass is determined by Size Exclusion Chromatography (SEC). A test portion of the polymer solution corresponding to 90 mg of dry matter is introduced into a 10 mL flask. Mobile phase, supplemented with 0.04% dimethylformamide (DMF), is added to a total mass of 10 g. The composition of this mobile phase is as follows: NaHCCU: 0.05 mol / L, NaNCU: 0.1 mol / L, triethanolamine: 0.02 mol / L, NaN3 0.03% by mass.The CES system consists of a Waters 510 isocratic pump with a flow rate set at 0.8 mL / min, a Waters 717+ autosampler, an oven containing a Waters Guard Column Ultrahydrogel precolumn 6 cm long and 40 mm inner diameter, followed by a Waters Ultrahydrogel linear column 30 cm long and 7.8 mm inner diameter. Detection is ensured by means of a Waters RI 410 differential refractometer. The oven is heated to a temperature of 60°C and the refractometer is heated to a temperature of 45°C. The CES system is calibrated with a series of sodium polyacrylate standards supplied by Polymer Standard Service. molecular weight at the peak between 1000 g / mol and 1.106 g / mol and a polydispersity index between 1.4 and 1.7. The calibration curve is linear and takes into account the correction obtained using the flow marker: dimethylformamide (DMF). The acquisition and processing of the chromatogram are carried out using the PSS WinGPC Scientific v 4.02 software. The chromatogram obtained is integrated into the area corresponding to molecular weights greater than 250 g / mol.

[0384] Example 1

[0385] In a 1 liter glass reactor equipped with stirring, a thermometer and a cooling system, a charge of 4.365 g of sodium hypophosphite monohydrate is introduced at room temperature into 357 g of deionized water. 3 charges are prepared to be introduced in parallel for 160 minutes:

[0386] - In a first beaker, weigh 540.8 g of acrylic acid and 95.44 g of acrylate of ethyl.

[0387] - In a second beaker, weigh 5.297g of sodium persulfate and dissolve with 82g of water.

[0388] - In a third beaker, 39.28 g of sodium hypophosphite mo- nohydrate which is dissolved in 50 g of deionized water.

[0389] After 160 min of adding the contents of the three beakers at 97°C, the pumps are rinsed and the assembly is cooked again for 30 min at 97°C. A clear dispersion of copolymer is obtained with a dry matter concentration of 57%. The aqueous GPC analysis of this polymer gives us an Mw of 2970 g / mol.

[0390] Example 2

[0391] A 250 ml high pressure reactor was placed under nitrogen. It was filled with 30 bar of vinylidene fluoride at room temperature and 5 ml of a solution of a phosphorylated copolymer of acrylic acid and ethyl acrylate (50% by weight in water) according to Example 1. The acrylic acid / ethyl acrylate ratio is 90 / 10. Then, 80 ml of water was added to the reactor and it was heated to 83°C to obtain a pressure of 44 bar. The reaction is initiated by the sequential injection of potassium persulfate (KPS) (0.3 g of KPS in 10 ml of water), an exothermic reaction occurs and the pressure decreases by 2 bar. A solution of a phosphorylated copolymer of acrylic acid and ethyl acrylate according to Example 1 (12.5% ​​by weight in water) was added during the polymerization via sequential additions for a total of 5 mL. When no pressure drop was noticed, the reactor was cooled and opened.The product was isolated as a stable latex with little coagulum. The white polymeric powder was then obtained after drying the corresponding latex. The solid content is 21% by weight. The amount of acid is 5.1 mol%, measured by *H NMR. The product is characterized by 19F and 'H NMR. 19F NMR (282 MHz, . DMSO d6) ô -84.75, -85.14, -92.03, -92.54, -92.97, -94.78, -96.10, -98.45, -99.25, -102.84, -104.35, -107.40, -113.93, -116.20. *H NMR (300 MHz, DMSO) ô 6.62 - 5.88 (m, 1H), 3.34 - 2.60 (m, 44H), 2.25 (t, J = 13.7 Hz, 6H), 1.94 - 1.47 (m, 1H), 1.24 (t, J = 19.3 Hz, 1H). The signals with a chemical shift at -84.75 ppm and -85.14 ppm in 19F fluorine NMR are characteristic of the existence of a covalent bond between the phosphorylated copolymer of acrylic acid and ethyl acrylate and vinylidene fluoride.

[0392] Example 3 (comparative)

[0393] Example 2 is repeated but without adding phosphorylated acrylic acid and ethyl acrylate copolymer. A PVDF homopolymer is obtained having a solution viscosity close to that of the copolymer of Example 2.

[0394] The stability and adhesion of the polymer prepared in Example 2 and that prepared in Example 3 are evaluated according to the measurement methods described below. From the polymers of Examples 2 and 3, slurries are prepared.

[0395] Preparation of slurry

[0396] The slurry is prepared by first mixing 1.5 parts of carbon black in 15 parts of binder solution, the mixture is then stirred using a Thinky for 2 minutes at 2000rpm. This operation is repeated 4 times. The dispersion obtained is homogeneous and fluid. The resulting dispersion is mixed with 97 parts of NMC 811. The resulting slurry is mixed 4 times 2 minutes at 2000 rpm using a Thinky. 21.7 parts of NMP are then added. The solids content is 73.9%

[0397] Preparation of the electrodes

[0398] The positive electrodes are prepared using a coating line with two 1-meter furnaces. The furnace temperatures are 50 °C for the first and 90 °C for the second. The coating line speed is 0.2 meters / min and the blade gap is set at 180 qm. The resulting electrodes are then calendered to reduce the porosity to 25%.

[0399] Adhesion test

[0400] The adhesion of the active material to the current collector is characterized by a 180° peel test.

[0401] 2 samples of 7.5 cm2 are cut from the calendered electrode. An adhesive Double-sided tape is glued on one part of the electrode directly onto the active material. The other side is glued to a stainless steel plate. The tensile test is carried out between the stainless steel plate and the aluminum sample to peel the aluminum foil off the active material. Peel strength is defined as the force required to peel off a sample per unit length (here the width of 2 cm)

[0402] Rheological measurements of slurry

[0403] The viscosity of the slurry is determined by a rheometer. The slurry is poured between the rheometer and the gap is set at 300 pm. Flow curves are acquired by monitoring viscosity as a function of shear rate from 0.1 to 100 s-1. Viscoelastic properties are evaluated by measuring G' and G” as a function of oscillation strain between 0.1 and 100% at room temperature.

[0404] Table 1 below details the results obtained.

[0405] [Tables 1] Acid function (mol %) Slurry stability Adhesion before calendering Adhesion after calendering Example 2 (Inv.) 5.2 +40% 80 170 Example 3 (Comp.) 0 Gelation - -

[0406] The amount of acid function is determined by the integration of the 1H NMR signal of the C02H function.

[0407] As we can see, the polymer according to the invention has better stability and better adhesion compared to a polymer not containing an SL segment.

Claims

Claims

1. Polymer PI comprising residues derived from a fluorinated monomer Ml comprising a C=C double bond and at least one fluorine atom and one or more SI segments selected from formulae (Ia), (Ib), (Ic), (Id), (Ic), (If) and (Ig) or a mixture thereof -P(O)(OX)-[CR1R2CR3((X1)pC(O)R4)-(P(O)(OX))r]n- (Ia) -P(O)(OX)-[CR* R2 CR3 (OC(O)R4 )-(P(O)(OX))r]n- (Ib) -P(O)(OX)-[CR20R21CR22C(O)OC(O)CR23CR24R25-(P(O)(OX))r]n- (Ic) X -P(O)(OX)-[CR36R37CR38(CN)-(P(O)(OX))r]n- (If) -P(O)(OX)-[CR39R40CR41(C(O)NR42R43)-(P(O)(OX))r]n- (Ig) in which R1, R2, R3 are, independently of each other and independently for each unit n, selected from the group consisting of H, CO2 H, CrC5 alkyl; R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl; R4' is C1-C5 alkyl; n is an integer between 1 and 50000, advantageously between 2 and 40000, preferably between 3 and 30000, more preferably between 4 and 20000, in particular between 5 and 10000, more particularly between 5 and 5000, preferably between 5 and 3000; X is, independently for each unit n, selected from the group consisting of H, Na, K and Li; X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more hydroxyl groups; with w being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16, R17, R18, R19 are independently of each other and independent

2. pending for each unit w selected from the group consisting of H and C1-C5 alkyl; R4 is, independently for each n unit, selected from the group consisting of -NHC(CH3)2CH2C(O)CH3 and -OR5 with R5 selected from the group consisting of H and CrCi8 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -OPO32, SO3H, -CO2H, -C(O)OR9, -OC(O)R9, and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain; R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups; r is, independently for each n unit, 0 or 1; p, independently for each unit n, is 0 or 1; R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R 36, R37, R38, R39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more groups -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9. Polymer PI according to the preceding claim characterized in that said fluorinated monomer Ml is selected from the group consisting of vinylidene fluoride, vinyl fluoride; trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2 CF2SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE);trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, penta-;

3.

4. fluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chloro-difluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof. Polymer PI according to any one of the preceding claims characterized in that said fluorinated monomer Ml is vinylidene fluoride and said polymer PI optionally comprises residues of a monomer Ml' selected from the group consisting of vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(l,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2 CF2SO2F; a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, bromodifluoroethylene, chlorodifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof.Polymer PI according to any one of the preceding claims, characterized in that it comprises residues of a monomer M1” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) or a mixture thereof:. R6R7C=C(R8)((X2)PC(O)R10) (II); RnR12C=C(R13)(OC(O)R14) (III); R20 R2i c=CR22 C(O)OC(O)CR23 =CR24 R25 (IV); (VI) R36'R37'C=CR38'(CN) (VII); R39 R40 C=CR41 (C(O)NR42 R43 ) (VIII); wherein R6, R7 and R8 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl; R10 is, independently for each n unit, selected from the group consisting of -NHC(CH3)2CH2C(O)CH3 and -OR5' with R5' selected from the group consisting of H and CrCi8 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9, and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R9' is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups; X2 is selected from the group consisting of -[-C(O)OC(R16')(R17')C(R18')(R19')-]wr and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s);with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16', R17', R18', R19' are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1; R11, R12 and R13 are independently of each other selected from the group consisting of H and C1-C5 alkyl; R14 is C1-C5 alkyl; R20' R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35, R36', R37', R38', R39', R40' and R41' are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R42' and R43' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more groups -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.;

5. Polymer PI according to any one of the preceding claims characterized in that said one or more segment(s) SI is selected from formulae (Ia), (Ib), (Ic), (Id), (Ic), (If) and (Ig) as defined above or a mixture thereof; in which R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2 H, CrC3 alkyl; R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl; R4' is CrC3 alkyl; n is an integer between 1 and 5000, advantageously between 2 and 4000, preferably between 3 and 3000, more preferably between 4 and 2000, in particular between 5 and 1000, more particularly between 5 and 500; R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and CrCi8 alkyl optionally substituted by one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9 and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain; R9 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups; r is, independently for each n unit, 0 or 1; X is, independently for each unit n, selected from the group consisting of H, Na, K and Li; X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more hydroxyl group(s); with w being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R16, R17, R18, R19 are independently of each other, independently for each unit w selected from the group consisting of H and CrC3 alkyl; p, independently for each unit n, is 0 or 1; R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R 36, R37, R38, R39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more groups -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

6. Polymer PI according to any one of the preceding claims, characterized in that said one or more segment(s) SI is selected from formulae (Ia), (Ib), (Ic), (Id), (Ic), (If) and (Ig) as defined above or a mixture thereof; in which R1, R2, R3 are independently of each other and independently for each unit n, selected from the group consisting of H, CO2 H, CrC3 alkyl; R1', R2' and R3' are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C3 alkyl; R4' is CrC3 alkyl; n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50; R4 is, independently for each n unit, -OR5 with R5 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9 and a five or six membered heterocycle comprising at least one nitrogen atom in its ring chain; R9 is selected from the group consisting of CrC3 alkyl and C6-Ci2 aryl substituted with one or more CO2H functional groups; r is, independently for each n unit, 0 or 1; X is, independently for each unit n, selected from the group consisting of H, Na, K and Li; X1 is, independently for each unit n, selected from the group consisting of -[-C(O)OC(R16)(R17)C(R18)(R19)-]W- and a CrC3 alkyl hydrocarbon group optionally carrying one or more hydroxyl groups; with w being an integer from 1 to 10; R16, R17, R18, R19 are H; p, independently for each unit n, is 0 or 1; R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R 36, R37, R38, R39, R40 and R41 are, independently of each other and independently for each unit n, selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R42 and R43 are, independently of each other and independently for each unit n, selected from the group consisting of H and Ci - Cio alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO32, -C(O)OR9, -OC(O)R9.

7. Polymer PI according to any one of the preceding claims, characterized in that it comprises one or more segment(s) SI selected from the group consisting of: -P(O)(OX)-[CH(CO2H)CH(CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2OH)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH(OH)CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH(CH3)CH2(OH))-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2-OC(O)-CH2CH2CO2H)-(P(O)(OX))r] n”? -P(O)(OX)-[CH2CH(CO2CH2CH2-OC(O)-C6H4CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2CH2CH(CO2H)CH2CH2CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH(CH3)2)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2C4H9)-(P(O)(OX))r]n-,-P(O)(OX)-[CH2C(CH3)(CO2C5H11)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH2CH2CH3)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2CH(CH3)2)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2C4H9)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CO2C5H11)-(P(O)(OX))r]n-, -P(O)(OX)-[CH(CH3)CH(CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH2CO2H)(CO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH((CO2CH2CH2)wCO2H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(CN)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(C(O)NH2)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2CH2CH2OPO32 )-(P(O)(OX))r]n-, -P(O)(OX)-[CH2CH(NHC(CH3)2CH2SO3H)-(P(O)(OX))r]n-, -P(O)(OX)-[CH2C(CH3)(CO2C(O)OC(CH3)=CH2)-(P(O)(OX))r]n-, HH 4QXOX)P- ——(— (KOXOX) X— L- ,and HH "(Os(OX)Pi...................4-------- : / \ î i HHH À™"H i 1 h —yl ^ / \ — —! 1! -P(O)(OX)-[CH2CH(C(O)NHCH2OH)-(P(O)(OX))r]n-,or a mixture thereof; wherein r is, independently for each unit n, 0 or 1; X is, independently for each unit n, selected from the group consisting of H, Na, K and Li; n is an integer between 2 and 500, advantageously between 3 and 400, preferably between 4 and 300, more preferably between 5 and 200, in particular between 5 and 100, more particularly between 5 and 50.

8. Polymer PI according to any one of the preceding claims, characterized in that said one or more segment(s) SI is covalently linked to at least one of the residues of said fluorinated monomer Ml or Ml' if present or Ml” if present via a functional group -P(O)(OX) of said segment SI; X is, independently for each unit n, selected from the group consisting of H, Na, K and Li.

9. Process for preparing said polymer PI according to any one of the preceding claims, characterized in that it comprises, in a reactor, a step of polymerization in an aqueous medium of said fluorinated monomer Ml as defined in any one of claims 1 to 3 in the presence of a compound SI' comprising one or more segment(s) SI as defined in any one of claims 1, 4 to 7.

10. Process according to the preceding claim, characterized in that said compound SI' is obtained by reaction between an aqueous solution comprising a hypophosphite salt [H2P(O)(O )]xMy+ and one or more monomer(s) Ml” of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) as defined in claim 4, or a mixture thereof; M is H, an alkali or alkaline earth metal; and x and y are 1 if M is H or an alkali metal or x and y are 2 if M is an alkaline earth metal.

11. Process according to any one of claims 9 or 10 characterized in that said fluorinated monomer Ml is vinylidene fluoride and optionally the polymerization step is carried out in the presence of a monomer Ml' as defined in claim 3; or of a monomer Ml” as defined in claim 4.

12. A composition comprising said polymer PI according to any one of claims 1 to 8 and a fluoropolymer P2 or a hydrophilic polymer P3 or a mixture of both polymers P2 and P3; said fluoropolymer P2 being selected from the group consisting of vinylidene fluoride homopolymer or copolymer of vinylidene fluoride with a monomer M2 selected from the group consisting of vinyl fluoride; trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); a monomer of formula CF2=CFOCF2CF(CF3)OCF2CF2X3 in which X3 is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; a monomer of formula CF2=CFOCF2 CF2SO2F;a monomer of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the monomer of formula R'CH2OCF=CF2 in which R' is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the monomer of formula R”OCF=CH2 in which R” is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-1-propene or a mixture thereof; said hydrophilic polymer P3 comprising residues of a monomer M3 of formula (II), (III), (IV), (V), (VI), (VII) or (VIII) as defined in claim 4.;

13. A separator for an electrochemical device selected from the group: Li-ion, capacitor, electric double layer capacitor, and membrane electrode assembly (MEA) for a fuel cell, said separator comprising a porous support and said PI polymer according to any one of the preceding claims 1 to 8 or said composition according to claim 12.

14. A Li-ion secondary battery comprising an anode, a cathode and a separator, wherein said separator is according to the preceding claim.

15. A binder for a Li-ion battery comprising said PI polymer according to any one of preceding claims 1 to 8 or said composition according to claim 12.

16. Electrode for a lithium-ion battery comprising a metal collector of which at least one face is covered with a layer of substrate containing an active substance and a binder, characterized in that said binder is according to the preceding claim.

17. A Li-ion secondary battery comprising an anode, a cathode and a separator, wherein the anode or the cathode is an electrode according to the preceding claim.