Hyperbranched fluoroelastomer additive

Patent metadata

Field	Value
Publication number	US-9688786-B2
Application number	US-201214123931-A
Country	US
Kind code	B2
Filing date	Jun 7, 2012
Priority date	Jun 9, 2011
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

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 R 1 , R 2 , R 3 , R 4 , R 5 and R 6 , equal or different from each other, are H or C 1 -C 5 alkyl; Z is a linear or branched C 1 -C 18 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.

First claim

The invention claimed is:

1. A hyperbranched (per)fluoroelastomer [fluoroelastomer (B)] comprising recurring units derived from a bis-olefin [bis-olefin (OF)] having general formula:

wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 , equal or different from each other, are H or C 1 -C 5 alkyl; Z is a linear or branched C 1 -C 18 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) C 2 -C 8 perfluoroolefins;
(b) hydrogen-containing C 2 -C 8 olefins;
(c) C 2 -C 8 chloro and/or bromo and/or iodo-fluoroolefins;
(d) (per)fluoroalkylvinylethers of formula CF 2 ═CFOR f , wherein R f is a C 1 -C 6 (per)fluoroalkyl group;
(e) (per)fluoro-oxy-alkylvinylethers of formula CF 2 ═CFOX, wherein X is a C 1 -C 12 ((per)fluoro)-oxyalkyl comprising catenary oxygen atoms;
(f) (per)fluorodioxoles having formula:

wherein R f3 , R f4 , R f5 , R f6 , equal or different from each other, are independently selected from fluorine atoms and C 1 -C 6 (per)fluoroalkyl groups, optionally comprising one or more than one oxygen atom;
(g) (per)fluoro-methoxy-vinylethers having formula:
CFX 2 ═CX 2 OCF 2 OR″ f

wherein R″ f is selected from linear or branched C 1 -C 6 (per)fluoroalkyls; C 5 -C 6 cyclic (per)fluoroalkyls; and linear or branched C 2 -C 6 (per)fluorooxyalkyls comprising from 1 to 3 catenary oxygen atoms, and each X 2 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 CH 2 ═CH—R f , wherein R f is a C 1 -C 6 perfluoroalkyl group; chlorotrifluoroethylene; (per)fluoroalkylvinylethers of formula CF 2 ═CFOR f , wherein R f is selected from CF 3 , C 2 F 5 , and C 3 F 7 ; (per)fluoro-oxy-alkylvinylethers of formula CF 2 ═CFOX, wherein X is perfluoro-2-propoxypropyl; (f) (per)fluorodioxoles having formula:

wherein R f3 , R f4 , R f5 , R f6 are each independently selected from —CF 3 , —C 2 F 5 , —C 3 F 7 , —OCF 3 , —OCF 2 CF 2 OCF 3 ; and (per)fluoro-methoxy-vinylethers having formula:
CFX 2 ═CX 2 OCF 2 OR″ f

wherein X 2 is F and R″ f is selected from —CF 2 CF 3 , —CF 2 CF 2 OCF 3 , and —CF 3 .

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 C 1-5 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 OR B , wherein R B 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 C 1-5 alkyl or (per)fluoroalkyl group.

6. The fluoroelastomer (B) of claim 5 , wherein E is a —(CF 2 ) 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 δ J comprised between 0.2 and 0.7, wherein tan δ J 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 extrudi

Assignees

• Fantoni Matteo
• Comino Giovanni
• Apostolo Marco
• Solvay Specialty Polymers It

Inventors

• Fantoni Matteo
• Comino Giovanni
• Apostolo Marco

Classifications

• C08F14/26 Primary

  Tetrafluoroethene · CPC title

• C08F214/262

  with fluorinated vinyl ethers · CPC title

• C08F214/265

  with non-fluorinated comonomers · CPC title

• C08F214/26 Primary

  Tetrafluoroethene · CPC title