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A process for manufacturing a (per)fluoroelastomer having a heat of fusion of less than 5 J/g as measured by ASTM D-3418-08, comprising polymerizing at least one fluorinated monomer in the presence of at least one initiator in a polymerization medium comprising: (A) water; (B) at least one fluorinat

A process for manufacturing a (per)fluoroelastomer having a heat of fusion of less than 5 J/g as measured by ASTM D-3418-08, comprising polymerizing at least one fluorinated monomer in the presence of at least one initiator in a polymerization medium comprising: (A) water; (B) at least one fluorinated surfactant surfactant (FS) having formula (I) here below, wherein: X1, X2 and X3, equal to or different from each other, are independently selected from the group consisting of H, F and C1-C6 (per)fluoroalkyl groups, optionally comprising one or more catenary or non-catenary oxygen atoms,RF represents a divalent perfluorinated C1-C3 bridging group,L represents a bond or a divalent group andY represents a hydrophilic functionality selected from anionic functionalities, cationic functionalities and non-ionic functionalities;(C) at least one fluorinated compound compound (F) different from surfactant (FS);wherein said polymerization medium has a pH value of less than 7.

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1. A process for manufacturing a (per)fluoroelastomer having a heat of fusion of less than 5 J/g as measured by ASTM D-3418-08, said process comprising polymerizing at least one fluorinated monomer in the presence of at least one initiator in a polymerization medium comprising: (A) water;(B) at leas

1. A process for manufacturing a (per)fluoroelastomer having a heat of fusion of less than 5 J/g as measured by ASTM D-3418-08, said process comprising polymerizing at least one fluorinated monomer in the presence of at least one initiator in a polymerization medium comprising: (A) water;(B) at least one fluorinated surfactant [surfactant (FS)] having formula (I) here below: wherein: X1, X2 and X3, equal to or different from each other, are independently selected from the group consisting of H, F and C1-C6 (per)fluoroalkyl groups, optionally comprising one or more catenary or non-catenary oxygen atoms,RF represents a divalent perfluorinated C1-C3 bridging group,L represents a bond or a divalent group andY represents a hydrophilic functionality selected from the group consisting of anionic functionalities, cationic functionalities and non-ionic functionalities; and(C) at least one fluorinated compound [compound (F)] different from surfactant (FS);wherein said polymerization medium has a pH value of less than 7. 2. The process of claim 1, wherein the hydrophilic functionality Y of the surfactant (FS) is selected from the group consisting of anionic functionalities of formulae: wherein Xa is a hydrogen atom, a monovalent metal, or an ammonium group of formula —N(R′n)4, wherein R′n, equal or different at each occurrence, is a hydrogen atom or a C1-C6 hydrocarbon group. 3. The process of claim 1, wherein the surfactant (FS) complies with formula (II) here below: wherein X1, X2 and X3, equal to or different from each other, are independently selected from the group consisting of H, F and C1-C6 (per)fluoroalkyl groups, optionally comprising one or more catenary or non-catenary oxygen atoms,RF represents a divalent perfluorinated C1-C3 bridging group,Y represents a hydrophilic functionality selected from the group consisting of anionic functionalities, cationic functionalities and non-ionic functionalities. 4. The process of claim 1, wherein the surfactant (FS) complies with formula (VIII) here below: wherein RF represents a divalent perfluorinated C1-C3 bridging group and Xa is a hydrogen atom, a monovalent metal, or an ammonium group of formula —N(R′n)4, wherein R′n, equal or different at each occurrence, is a hydrogen atom or a C1-C6 hydrocarbon group, X*1 and X*2, equal to or different from each other, are independently a fluorine atom, a —R′f group or a —OR′f group, wherein R′f is a C1-C3 perfluoroalkyl group, R*F is a divalent fluorinated group and k is an integer from 1 to 3. 5. The process of claim 1, wherein the surfactant (FS) complies with formula (IX) here below: wherein RF has the same meaning as in claim 1 and Xa is a hydrogen atom, a monovalent metal, or an ammonium group of formula —N(R′n)4, wherein R′n, equal or different at each occurrence, is a hydrogen atom or a C1-C6 hydrocarbon group, X*1 and X*2, equal to or different from each other, are independently a fluorine atom, a —R′f group or a —OR′f group, wherein R′f is a C1-C3 perfluoroalkyl group, RF1 is a fluorine atom or a —CF3 group and k is an integer from 1 to 3. 6. The process of claim 1, wherein the compound (F) is a functional (per)fluoropolyether (functional PFPE) comprising at least one (per)fluoropolyoxyalkylene chain [chain (RF)] and at least one functional end-group selected from the group consisting of carboxylic acid, phosphonic acid and sulphonic acid groups. 7. The process of claim 1 or claim 6, wherein the compound (F) complies with formula (XII) here below: T1-(CFW1)p1—O—RF—(CFW2)p2-T2  (XII)wherein: RF is a (per)fluoropolyoxyalkylene chain [chain (RF)];T1 and T2, equal to or different from each other, are selected from the group consisting of:i) functional end-groups selected from the group consisting of carboxylic acid, phosphonic acid and sulphonic acid groups, andii) non-functional end-groups selected from the group consisting of a fluorine atom, a chlorine atom and a C1-C3 (per)fluoroalkyl group comprising, optionally, one or more chlorine atoms, with the proviso that at least one of T1 and T2 is a functional end-group as defined above; W1 and W2, equal to or different from each other, independently represent a fluorine atom or a —CF3 group;p1 and p2, equal to or different from each other, are independently integers comprised between 1 and 3. 8. The process of claim 1, wherein the compound (F) complies with formula (XIV) here below: HOOC—CF2—O—(CF2)n′(CF2CF2O)m′—CF2—COOH  (XIV) wherein n′ and m′ are independently integers >0 such that the number average molecular weight of the compound (F) is at least 1000, wherein recurring units of (CF2) and (CF2CF2O) are generally statistically distributed along the perfluoropolyoxyalkylene chain. 9. The process of claim 1, wherein the initiator is selected from the group consisting of inorganic initiators and peroxide initiators. 10. The process of claim 1, wherein the polymerization medium has a pH value of less than 5. 11. The process of claim 1, wherein said polymerization medium has a pH value of less than 3.