FLUOROPOLYMER COMPOSITIONS

Abstract

The present invention pertains to a fluoropolymer composition, to a process for the manufacture of said fluoropolymer composition and to uses of said fluoropolymer composition in various applications, in particular to uses of fluoropolymer films obtainable therefrom in electrical or electronic devices.

Claims

1. A composition [composition (C)] comprising: (A) at least one fluoropolymer [polymer (F)] comprising: from 30% to 82% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from vinylidene fluoride (VDF) and from 18% to 70% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from trifluoroethylene (TrFE) and, optionally, at least one fluorinated monomer [monomer (F)] different from VDF and TrFE, and (B) a liquid medium [medium (L)] comprising one or more organic solvents selected from the group consisting of diesters of formula (I.sub.de), esteramides of formula (I.sub.ea) and diamides of formula (I.sub.da):
R.sup.1O(O)CZ.sub.deC(O)OR.sup.2(I.sub.de)
R.sup.3O(O)CZ.sub.eaC(O)NR.sup.4R.sup.5(I.sub.ea)
R.sup.5R.sup.4N(O)CZ.sub.daC(O)NR.sup.4R.sup.5(I.sub.da) wherein: R.sup.1 and R.sup.2, equal to or different from each other, are independently selected from the group consisting of C.sub.1-C.sub.3 hydrocarbon groups, R.sup.3 is selected from the group consisting of C.sub.1-C.sub.20 hydrocarbon groups, and R.sup.4 and R.sup.5, equal to or different from each other, are independently selected from the group consisting of hydrogen and C.sub.1-C.sub.36 hydrocarbon groups, optionally substituted, or wherein R.sup.4 and R.sup.5, taken together, form a cyclic moiety including the nitrogen atom to which they are bound, said cyclic moiety being optionally substituted and/or optionally comprising one or more heteroatoms, and mixtures thereof, and Z.sub.de, Z.sub.ea and Z.sub.da, equal to or different from each other, are independently linear or branched C.sub.2-C.sub.10 divalent alkylene groups.

2. The composition (C) according to claim 1, wherein the medium (L) is free from dimethylsulfoxide (DMSO).

3. The composition (C) according to claim 1, wherein the polymer (F) comprises: from 45% to 81% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from vinylidene fluoride (VDF), from 19% to 55% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from trifluoroethylene (TrFE) and optionally, from 0.01% to 15% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from at least one hydrogenated monomer (H).

4. The composition (C) according to claim 1, wherein the polymer (F) comprises: from 30% to 80% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from vinylidene fluoride (VDF), from 19% to 55% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from trifluoroethylene (TrFE), from 1% to 15% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from at least one monomer (F) different from VDF and TrFE and optionally, from 0.01% to 8% by moles, with respect to the total amount by moles of recurring units of the polymer (F), of recurring units derived from at least one hydrogenated monomer (H).

5. The composition (C) according to claim 1, wherein the polymer (F) comprises one or more chain branches comprising end groups of formulae CF.sub.2H and/or CF.sub.2CH.sub.3.

6. The composition (C) according to claim 1, wherein the polymer (F) comprises one or more chain branches comprising end groups of formulae CF.sub.2H and/or CF.sub.2CH.sub.3 in an amount of at least 30 mmoles/Kg per Kg of vinylidene fluoride (VDF) recurring units.

7. The composition (C) according to claim 1, wherein the medium (L) comprises a total amount of one or more organic solvents selected from the group consisting of diesters of formula (I.sub.de), esteramides of formula (I.sub.ea) and diamides of formula (I.sub.da) of at least 50% by weight with respect to the total weight of the medium (L).

8. The composition (C) according to claim 1, said composition (C) comprising: (A) from 0.1% to 40% by weight of at least one polymer (F) and (B) from 60% to 99.9% by weight of a medium (L).

9. The composition (C) according to claim 1, said composition (C) further comprising one or more additives selected from the group consisting of crosslinking agents and crosslinking initiators.

10. A process for the manufacture of the composition (C) according to claim 1, said process comprising: heating a mixture comprising at least one polymer (F) and a medium (L), under stirring, thereby providing the composition (C).

11. The process according to claim 10, wherein the polymer (F) in the mixture is used either in the form of particles or in the form of pellets.

12. The process according to claim 10, wherein the mixture is heated under stirring at a temperature of at least 20 C.

13. The process according to claim 10, wherein the mixture is heated under stirring at a temperature of at most 80 C.

14. A process for the manufacture of a fluoropolymer film [film (F)], said process comprising: applying a composition (C) according to claim 1 onto at least one surface of a substrate thereby providing a wet film, and drying the wet film thereby providing the fluoropolymer film [film (F)].

15. A process for the manufacture of an electrical or electronic device, said process comprising: (i) manufacturing a fluoropolymer film [film (F)] according to the process of claim 14, and (ii) using the film (F) provided in step (i) for manufacturing said electrical or electronic device.

16. The process according to claim 14, wherein the wet film is dried at a temperature comprised between 60 C. and 200 C.

Description

EXAMPLE 1

[0339] A fluoropolymer composition was manufactured by dissolving, under stirring, either at 25 C. or at 50 C., any of polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the form of particles in solvent (A). The fluoropolymer composition was kept stirred until complete dissolution of the polymer (F) in the medium (L).

EXAMPLE 2

[0340] A fluoropolymer composition was manufactured by dissolving, under stirring, either at 25 C. or at 50 C., any of polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the form of particles in solvent (B). The fluoropolymer composition was kept stirred until complete dissolution of the polymer (F) in the medium (L).

EXAMPLE 3

[0341] A fluoropolymer composition was manufactured by dissolving, under stirring, either at 25 C. or at 50 C., any of polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the form of particles in solvent (C). The fluoropolymer composition was kept stirred until complete dissolution of the polymer (F) in the medium (L).

EXAMPLE 4

[0342] A fluoropolymer composition was manufactured by dissolving, under stirring, either at 25 C. or at 50 C., any of polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the form of particles in solvent (D). The fluoropolymer composition was kept stirred until complete dissolution of the polymer (F) in the medium (L).

COMPARATIVE EXAMPLE 1

[0343] A fluoropolymer composition was manufactured by dispersing, under stirring, either at 25 C. or at 50 C., any of polymer (F-4), polymer (F-5) or polymer (F-6) in the form of particles in solvent (A).

COMPARATIVE EXAMPLE 2

[0344] A fluoropolymer composition was manufactured by dispersing, under stirring, either at 25 C. or at 50 C., any of polymer (F-4), polymer (F-5) or polymer (F-6) in the form of particles in solvent (B).

COMPARATIVE EXAMPLE 3

[0345] A fluoropolymer composition was manufactured by dispersing, under stirring, either at 25 C. or at 50 C., any of polymer (F-4), polymer (F-5) or polymer (F-6) in the form of particles in solvent (C).

COMPARATIVE EXAMPLE 4

[0346] A fluoropolymer composition was manufactured by dispersing, under stirring, either at 25 C. or at 50 C., any of polymer (F-4), polymer (F-5) or polymer (F-6) in the form of particles in solvent (D).

COMPARATIVE EXAMPLE 5

[0347] A fluoropolymer composition was manufactured by dispersing, under stirring, either at 25 C. or at 50 C., any of polymer (F-1), polymer (F-2), polymer (F-3), polymer (F-4), polymer (F-5), polymer (F-6) or polymer (F-7) in the form of particles in a liquid medium consisting of the solvent (E).

COMPARATIVE EXAMPLE 6

[0348] A fluoropolymer composition was manufactured by dispersing, under stirring, either at 25 C. or at 50 C., any of polymer (F-1), polymer (F-2), polymer (F-3), polymer (F-4), polymer (F-5), polymer (F-6) or polymer (F-7) in the form of particles in a liquid medium consisting of the solvent (F).

[0349] As shown in Table 2 hereinbelow, any of polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) advantageously dissolved in any of solvent (A), solvent (B), solvent (C) or solvent (D) thereby providing clear solutions with no phase separation up to 30% by weight, with respect to the total weight of said solution, of said polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7).

[0350] In particular, polymer (F-2) and polymer (F-7) provided for faster dissolution in any of solvent (A), solvent (B), solvent (C) or solvent (D) thereby providing homogeneous solutions comprising up to 30% by weight, with respect to the total weight of said solution, of said polymer (F-2) or polymer (F-7).

TABLE-US-00002 TABLE 2 Ex. 1 Ex. 2 Ex. 3 Ex. 4 Solvent (A) Solvent (B) Solvent (C) Solvent (D) 25 C. 50 C. 25 C. 50 C. 25 C. 50 C. 25 C. 50 C. Polymer (F-1) 25% S 25% S 25% S 25% S 25% S 25% S 25% S 25% S Polymer (F-2) 25% S 25% S 25% S 25% S 25% S 25% S 25% S 25% S Polymer (F-3) 25% S 25% S 10% S 10% S 20% S 20% S 20% S 20% S Polymer (F-7) 30% S 30% S 15% S 15% S 20% S 20% S 20% S 20% S

[0351] On the other hand, as shown in Table 3 hereinbelow, the fluoropolymer compositions according to Comparative Examples 1 to 4 were turbid or cloudy due to formation of polymer aggregates even at 5% by weight, with respect to the total weight of said composition, of polymer (F-4), polymer (F-5) or polymer (F-6) in any of solvent (A), solvent (B), solvent (C) or solvent (D).

TABLE-US-00003 TABLE 3 C. Ex. 1 C. Ex. 2 C. Ex. 3 C. Ex. 4 Solvent (A) Solvent (B) Solvent (C) Solvent (D) 25 C. 50 C. 25 C. 50 C. 25 C. 50 C. 25 C. 50 C. Polymer (F-4) 5% I 5% I 10% I 10% I 5% I 5% I 25% I 25% I Polymer (F-5) 10% I 10% I 10% I 10% I 10% I 10% I 10% I 10% I Polymer (F-6) 10% I 10% I 10% I 10% I 10% I 10% I 25% I 25% I

[0352] Also, as shown in Table 4 hereinbelow, the fluoropolymer compositions according to Comparative Examples 5 and 6 were turbid or cloudy due to formation of polymer aggregates even at 1% by weight, with respect to the total weight of said composition, of polymer (F-1), polymer (F-2), polymer (F-3), polymer (F-4), polymer (F-5), polymer (F-6) or polymer (F-7) in any of solvent (E) or solvent (F).

TABLE-US-00004 TABLE 4 C. Ex. 5 C. Ex. 6 Solvent (E) Solvent (F) 25 C. 50 C. 25 C. 50 C. Polymer (F-1) 1% I 1% I 1% I 1% I Polymer (F-2) 1% I 1% I 1% I 1% I Polymer (F-3) 1% I 1% I 1% I 1% I Polymer (F-4) 1% I 1% I 1% I 1% I Polymer (F-5) 1% I 1% I 1% I 1% I Polymer (F-6) 1% I 1% I 1% I 1% I Polymer (F-7) 1% I 1% I 1% I 1% I

[0353] The composition (C) according to the present invention may be advantageously used in a process for the manufacture of fluoropolymer films thereby providing for homogeneous fluoropolymer films having good mechanical properties to be suitably used in various applications including electrical or electronic devices.