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The invention pertains to a hyperbranched (per)fluoroelastomer fluoroelastomer (B) comprising recurring units derived from a bis-olefin bis-olefin (OF) having general formula (I): wherein R1, R2, R3, R4, R5 and R6, equal or different from each other, are H or C1-C5 alkyl; Z is a linear or branched C

The invention pertains to a hyperbranched (per)fluoroelastomer fluoroelastomer (B) comprising recurring units derived from a bis-olefin bis-olefin (OF) having general formula (I): wherein R1, R2, R3, R4, R5 and R6, equal or different from each other, are H or C1-C5 alkyl; Z is a linear or branched C1-C18 alkylene or cycloalkylene radical, optionally containing oxygen atoms, preferably at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical, said fluoroelastomer (B) having a slope in G′ curve such that the ratio: G′100/G′0.01 is of less than 10, when determined at 260° C. according to ASTM D4440 standard, wherein G′100 is the storage modulus at a shear rate of 100 rad/sec and G′0.01 is the storage modulus at a shear rate of 0.01 rad/sec, to compositions comprising the same, and to a process for their manufacture.

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1. A hyperbranched (per)fluoroelastomer [fluoroelastomer (B)] comprising recurring units derived from a bis-olefin [bis-olefin (OF)] having general formula: wherein R1, R2, R3, R4, R5 and R6, equal or different from each other, are H or C1-C5 alkyl; Z is a linear or branched C1-C18 alkylene or cyclo

1. A hyperbranched (per)fluoroelastomer [fluoroelastomer (B)] comprising recurring units derived from a bis-olefin [bis-olefin (OF)] having general formula: wherein R1, R2, R3, R4, R5 and R6, equal or different from each other, are H or C1-C5 alkyl; Z is a linear or branched C1-C18 alkylene or cycloalkylene radical, optionally containing oxygen atoms, optionally at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical,said fluoroelastomer (B) having a slope in G′ curve such that the ratio: G′100/G′0.01 is less than 10, when determined at 260° C. according to ASTM D4440 standard, wherein G′100 is the storage modulus at a shear rate of 100 rad/sec and G′0.01 is the storage modulus at a shear rate of 0.01 rad/sec. 2. The fluoroelastomer (B) of claim 1, comprising recurring units derived from (per)fluorinated monomers selected from the group consisting of: (a) C2-C8 perfluoroolefins;(b) hydrogen-containing C2-C8 olefins;(c) C2-C8 chloro and/or bromo and/or iodo-fluoroolefins;(d) (per)fluoroalkylvinylethers of formula CF2═CFORf, wherein Rf is a C1-C6 (per)fluoroalkyl group;(e) (per)fluoro-oxy-alkylvinylethers of formula CF2═CFOX, wherein X is a C1-C12 ((per)fluoro)-oxyalkyl comprising catenary oxygen atoms;(f) (per)fluorodioxoles having formula: wherein Rf3, Rf4, Rf5, Rf6, equal or different from each other, are independently selected from fluorine atoms and C1-C6 (per)fluoroalkyl groups, optionally comprising one or more than one oxygen atom; (g) (per)fluoro-methoxy-vinylethers having formula: CFX2═CX2OCF2OR″f wherein R″f is selected from linear or branched C1-C6 (per)fluoroalkyls; C5-C6 cyclic (per)fluoroalkyls; and linear or branched C2-C6 (per)fluorooxyalkyls comprising from 1 to 3 catenary oxygen atoms, and each X2 is independently selected from F and H. 3. The fluoroelastomer (B) of claim 2, comprising recurring units derived from bis-olefin (OF), from tetrafluoroethylene (TFE) and from perfluoromethylvinylether (MVE), MVE being generally comprised in an amount of 25 to 45% moles, with respect to the sum of recurring units derived from TFE and MVE. 4. The fluoroelastomer (B) of claim 2, comprising recurring units derived from (per)fluorinated monomers selected from the group consisting of: tetrafluoroethylene; hexafluoroisobutylene; vinyl fluoride; vinylidene fluoride; trifluoroethylene; perfluoroalkyl ethylenes of formula CH2═CH—Rf, wherein Rf is a C1-C6 perfluoroalkyl group; chlorotrifluoroethylene; (per)fluoroalkylvinylethers of formula CF2═CFORf, wherein Rf is selected from CF3, C2F5, and C3F7; (per)fluoro-oxy-alkylvinylethers of formula CF2═CFOX, wherein X is perfluoro-2-propoxypropyl; (f) (per)fluorodioxoles having formula: wherein Rf3, Rf4, Rf5, Rf6 are each independently selected from —CF3, —C2F5, —C3F7, —OCF3, —OCF2CF2OCF3; and (per)fluoro-methoxy-vinylethers having formula: CFX2═CX2OCF2OR″f wherein X2 is F and R″f is selected from —CF2CF3, —CF2CF2OCF3, and —CF3. 5. The fluoroelastomer (B) of claim 1, wherein said bis-olefin (OF) is selected from the group consisting of compounds of formulae (OF-1), (OF-2) and (OF-3): wherein j is an integer between 2 and 10, and R1, R2, R3, R4, equal or different from each other, are H, F or a C1-5 alkyl or (per)fluoroalkyl group; wherein each of A, equal or different from each other and at each occurrence, is independently selected from F, Cl, and H; each of B, equal or different from each other and at each occurrence, is independently selected from F, Cl, H and ORB, wherein RB is a branched or straight chain alkyl radical which can be partially, substantially or completely fluorinated or chlorinated; E is a divalent group having 2 to 10 carbon atoms, optionally fluorinated, which may be inserted with ether linkages; wherein E, A and B have the same meaning as above defined; R5, R6, R7, equal or different from each other, are H, F or a C1-5 alkyl or (per)fluoroalkyl group. 6. The fluoroelastomer (B) of claim 5, wherein E is a —(CF2)m— group, wherein m is an integer from 3 to 5. 7. The fluoroelastomer (B) of claim 1, possessing a slope in G′ curve as a function of shear rate such that the ratio G′100/G′0.01 is less than 5 when determined at 260° C. according to ASTM D4440 standard. 8. The fluoroelastomer (B) of claim 7, possessing a slope in G′ curve as a function of shear rate such that the ratio G′100/G′0.01 is less than 2, when determined at 260° C. according to ASTM D4440 standard. 9. The fluoroelastomer (B) of claim 1, said fluoroelastomer (B) being characterized by the fact that G′J exceeds G″J, wherein G′J is the storage modulus at shear rate J, and G″J is the loss modulus at same shear rate J, said shear rate being comprised between 0.01 and 100 rad/sec, when determined at 260° C. according to ASTM D4440 standard. 10. The fluoroelastomer (B) of claim 9, characterized by a ratio G′J/G″J of more than 5. 11. The fluoroelastomer (B) according to claim 1, possessing in its uncured state a solubility in perfluoroheptane at 50° C. of less than 10 g/l. 12. The fluoroelastomer (B) according to claim 11, possessing in its uncured state a solubility in perfluoroheptane at 50° C. of less than 5 g/l. 13. A composition comprising at least one fluoroelastomer (B) according to claim 1 and at least one (per)fluoroelastomer [fluoroelastomer (A)] different from fluoroelastomer (B) [composition (C)]. 14. The composition (C) according to claim 13, possessing a slope in G′ curve as a function of shear rate such that the ratio G′100/G′0.01 is generally comprised between 10 and 30, when determined at 260° C. according to ASTM D4440 standard, wherein G′100 is the storage modulus at a shear rate of 100 rad/sec and G′0.01 is the storage modulus at a shear rate of 0.01 rad/sec. 15. The composition (C) according to claim 13, being characterized by tan δJ comprised between 0.2 and 0.7, wherein tan δJ is the value of tan δ at shear rate J, for J ranging from 0.01 to 100. 16. A process for manufacturing the composition (C) according to claim 13, said process comprising mixing an aqueous dispersion of fluoroelastomer (A) and an aqueous dispersion of fluoroelastomer (B) and co-coagulating the same for yielding composition (C). 17. A process according to claim 16, said process comprising manufacturing said aqueous dispersion of fluoroelastomer (A) and said aqueous dispersion of fluoroelastomer (B) in a staged polymerization process, so as to obtain directly from polymerization a blend of an aqueous dispersion of fluoroelastomer (A) and an aqueous dispersion of fluoroelastomer (B). 18. A method for fabricating shaped articles, the method comprising moulding, calendering, or extruding the composition (C) according to claim 13, such that a shaped article is fabricated. 19. A peroxide curable composition [composition (PC)] comprising the composition according to claim 13 and at least one peroxide. 20. An ionically curable composition [composition (IC)] comprising the composition according to claim 13, at least one curing agent and at least one accelerator.