Hybrid polymers

Abstract

The present invention pertains to a polyurethane fluoropolymer [polymer (F.sub.p)] obtainable by reacting: (i) at least one fluoropolymer [polymer (F)] comprising one or more recurring units derived from at least one (meth)acrylic monomer [monomer (MA)] having formula (I) here below: wherein: R.sub.1, R.sub.2 and R.sub.3, equal to or different from each other, are independently selected from a hydrogen atom and a C.sub.1-C.sub.3 hydrocarbon group, R.sub.H is a C.sub.1-C.sub.10 hydrocarbon group comprising from 1 to 5 hydroxyl groups, x being an integer comprised between 1 and 5, and, optionally, comprising one or more functional groups selected from double bonds, epoxy, ester, ether and carboxylic acid groups, with (ii) at least one isocyanate compound comprising at least one isocyanate functional group [compound (I)], (iii) optionally in the presence of one or more chain extenders, said polyurethane fluoropolymer [polymer (F.sub.p)] comprising at least one bridging group having formula (a) here below: wherein: R.sub.H is a C.sub.1-C.sub.5 hydrocarbon group comprising from 1 to 5 urethane moieties, x being an integer comprised between 1 and 5, and, optionally, comprising one or more functional groups selected from double bonds, epoxy, ester, ether and carboxylic acid groups. The invention also pertains to a process for the manufacture of said polymer (F.sub.p) and to uses of said polymer (F.sub.p). ##STR00001##

Claims

1. A polyurethane fluoropolymer (F.sub.P) obtained by reacting: (i) at least one fluoropolymer (F) selected from: a polymer (F.sub.1), wherein polymer (F.sub.1) is manufactured by aqueous suspension polymerization or by an aqueous emulsion polymerization process and wherein polymer (F.sub.1) comprises recurring units derived from vinylidene fluoride (VDF) and from 0.01% to 10% by moles, based on the total moles of recurring units in polymer (F.sub.1), of recurring units derived from at least one (meth)acrylic monomer (MA) of formula (I): ##STR00015## wherein: R.sub.1, R.sub.2, and R.sub.3, equal to or different from each other, are independently selected from a hydrogen atom and a C.sub.1-C.sub.3 hydrocarbon group, R.sub.H is a C.sub.1-C.sub.10 hydrocarbon group optionally comprising one or more functional groups selected from double bonds, epoxy, ester, ether and carboxylic acid groups, and x is an integer between 1 and 5; or a polymer (F.sub.2), wherein polymer (F.sub.2) is manufactured by aqueous suspension polymerization or by an aqueous emulsion polymerization process and wherein polymer (F.sub.2) comprises recurring units derived from ethylene (E), from at least one fluorinated monomer (F) selected from tetrafluoroethylene (TFE), chlorotrifluoroethylene (CTFE), and mixtures thereof, and from 0.01% to 10% by moles, based on the total moles of recurring units in polymer (F.sub.2), of recurring units derived from at least one (meth)acrylic monomer (MA) of formula (I), with (ii) at least one isocyanate compound (I) comprising at least one isocyanate functional group, (iii) in the presence of one or more chain extenders selected from polyethylene glycols, said polyurethane fluoropolymer (F.sub.P) comprising at least one bridging group selected from bridging groups of formula (a): ##STR00016## wherein: R.sub.H is a C.sub.1-C.sub.10 hydrocarbon group optionally comprising one or more functional groups selected from double bonds, epoxy, ester, ether and carboxylic acid groups, and x is an integer between 1 and 5.

2. The polyurethane fluoropolymer (F.sub.P) according to claim 1, comprising: from 0.01% to 99.99% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one fluorinated block comprising a fluorocarbon chain, and from 99.99% to 0.01% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one hydrogenated block comprising a hydrocarbon chain, said blocks being linked to each other by one or more urethane moieties.

3. The polyurethane fluoropolymer (F.sub.P) according to claim 1, obtained by reacting: (i) at least 50% by weight, based on the total weight of fluoropolymer (F) and isocyanate compound (I), of at least one fluoropolymer (F), with (ii) less than 50% by weight, based on the total weight of fluoropolymer (F) and isocyanate compound (I), of at least one isocyanate compound (I), (iii) in the presence of one or more chain extenders.

4. The polyurethane fluoropolymer (F.sub.P) according to claim 3, comprising: at least 80% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one fluorinated block comprising a fluorocarbon chain, and at most 20% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one hydrogenated block comprising a hydrocarbon chain, said blocks being linked to each other by one or more urethane moieties.

5. The polyurethane fluoropolymer (F.sub.P) according to claim 1, obtained by reacting: (i) at least 50% by weight, based on the total weight of fluoropolymer (F), isocyanate compound (I) and chain extender, of at least one fluoropolymer (F), with (ii) less than 50% by weight, based on the total weight of fluoropolymer (F), isocyanate compound (I) and chain extender, of at least one isocyanate compound (I), and (iii) from 0.01% to 50% by weight, based on the total weight of fluoropolymer (F), isocyanate compound (I) and chain extender, of one or more chain extenders.

6. The polyurethane fluoropolymer (F.sub.P) according to claim 1, wherein the isocyanate compound (I) comprises at least one polyisocyanate compound (I.sub.P) comprising at least two isocyanate functional groups, and wherein the polyurethane fluoropolymer (F.sub.P) is obtained by reacting: (i) less than 50% by weight, based on the total weight of fluoropolymer (F) and polyisocyanate compound (I.sub.P), of at least one fluoropolymer (F), with (ii) at least 50% by weight, based on the total weight of fluoropolymer (F) and polyisocyanate compound (I.sub.P), of at least one polyisocyanate compound (I.sub.P), (iii) in the presence of one or more chain extenders.

7. The polyurethane fluoropolymer (F.sub.P) according to claim 6, comprising: at most 50% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one fluorinated block comprising a fluorocarbon chain, and at least 50% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one hydrogenated block comprising a hydrocarbon chain, said blocks being linked to each other by one or more urethane moieties.

8. A process for the manufacture of the polyurethane fluoropolymer (F.sub.P) according to claim 1, said process comprising blending at least one fluoropolymer (F), at least one isocyanate compound (I) and the one or more chain extenders, optionally in the presence of a liquid medium, under temperatures comprised between 20 C. and 300 C.

9. A membrane comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 1.

10. A membrane comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 3.

11. A polyurethane foam material comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 1.

12. A polyurethane foam material comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 6.

13. A membrane comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 4.

14. A membrane comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 5.

15. A polyurethane foam material comprising at least one polyurethane fluoropolymer (F.sub.P) according to claim 7.

16. The polyurethane fluoropolymer (F.sub.P) according to claim 2, comprising: from 0.05% to 99.95% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one fluorinated block comprising a fluorocarbon chain, and from 99.95% to 0.05% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one hydrogenated block comprising a hydrocarbon chain, said blocks being linked to each other by one or more urethane moieties.

17. The polyurethane fluoropolymer (F.sub.P) according to claim 4, comprising: at least 95% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one fluorinated block comprising a fluorocarbon chain, and at most 5% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one hydrogenated block comprising a hydrocarbon chain, said blocks being linked to each other by one or more urethane moieties.

18. The polyurethane fluoropolymer (F.sub.P) according to claim 7, comprising: at most 40% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one fluorinated block comprising a fluorocarbon chain, and at least 60% by weight, based on the weight of said polyurethane fluoropolymer (F.sub.P), of at least one hydrogenated block comprising a hydrocarbon chain, said blocks being linked to each other by one or more urethane moieties.

19. The polyurethane fluoropolymer (F.sub.P) according to claim 1, wherein polymer (F.sub.1) comprises from 0.1% to 1.5% by moles, based on the total moles of recurring units in polymer (F.sub.1), of the recurring units derived from at least one (meth)acrylic monomer (MA) of formula (I).

20. The polyurethane fluoropolymer (F.sub.P) according to claim 1, wherein polymer (F.sub.2) comprises 0.05% to 8% by moles, based on the total moles of recurring units in polymer (F.sub.2), of the recurring units derived from at least one (meth)acrylic monomer (MA) of formula (I).

21. The polyurethane fluoropolymer (F.sub.P) according to claim 1, wherein the one or more chain extenders are selected from polyethylene glycols of formula HO(CH.sub.2CHRO).sub.nR, wherein R is H or a C.sub.1-C.sub.5 alkyl group, R is H, and n is an integer comprised between 4 and 230000.

Description

EXAMPLE 1

Blend of Polymer (F1) with Di-Isocyanate (D1) (1.95% by Weight of Polymer (F1))

(1) The polymer (F1) and the di-isocyanate (D1) were blended in a rapid mixer at 300 rpm for 3 minutes to yield a powder mixture which was then processed by extrusion in a double screw 30-34 extruder (LEISTRITZ), equipped with 6 temperature zones and a 4 mm-2 holes die.

(2) Temperatures set points were set as follows:

(3) TABLE-US-00001 TABLE 1 Feed zone T1 T2 T3 T4 T5 180 C. 180 C. 180 C. 185 C. 185 C. 190 C.

(4) Screws speed was set at 100 rpm, with a feed rate of 20%, so as to yield a throughput rate of about 6 Kg/h, and a melt temperature of about 230 C. Extruded strands were cooled in a water bath, dried, calibrated and cut in a pelletizer.

(5) FT-IR spectroscopic analyses showed urethane peaks in the polyurethane fluoropolymer so obtained (1535 cm.sup.1).

(6) The polyurethane fluoropolymer had a contact angle towards water of 67.9 degrees and a melt viscosity of 100000 Pa.Math.s at 1 rad/s.

EXAMPLE 2

Blend of Polymer (F1) with Di-Isocyanate (D1) (6.5% by Weight of Polymer (F1))

(7) The same procedure as detailed under Example 1 was followed, but blending the polymer (F1) with 6.5% by weight of polymer (F1) of the di-isocyanate (D1).

(8) FT-IR spectroscopic analyses showed urethane peaks in the polyurethane fluoropolymer so obtained (1535 cm.sup.1).

(9) The polyurethane fluoropolymer was endowed with a melt viscosity so high that extrusion was not possible.

EXAMPLE 3

Blend of Polymer (F1) with Di-Isocyanate (D1) (0.65% by Weight of Polymer (F1))

(10) The same procedure as detailed under Example 1 was followed, but blending the polymer (F1) with 0.65% by weight of polymer (F1) of the di-isocyanate (D1).

(11) FT-IR spectroscopic analyses showed urethane peaks in the polyurethane fluoropolymer so obtained (1535 cm.sup.1).

(12) The polyurethane fluoropolymer had a contact angle towards water of 77.8 degrees.

EXAMPLE 4

Blend of Polymer (F1) with Di-Isocyanate (D2) (0.65% by Weight of Polymer (F1))

(13) The same procedure as detailed under Example 1 was followed, but blending the polymer (F1) with 0.65% by weight of polymer (F1) of the di-isocyanate (D2).

(14) FT-IR spectroscopic analyses showed urethane peaks in the polyurethane fluoropolymer so obtained (1535 cm.sup.1).

(15) The polyurethane fluoropolymer had a contact angle towards water of 65.9 degrees.

COMPARATIVE EXAMPLE 1

(16) The polymer (F1), free from urethane moieties, had a contact angle towards water of 90 degrees and a melt viscosity of 10000 Pa.Math.s at 1 rad/s.

COMPARATIVE EXAMPLE 2

(17) The SOLEF 6008 VDF homopolymer, free from hydroxyl groups and from urethane moieties, had a contact angle towards water of 87.1 degrees and a melt viscosity of 2000 Pa.Math.s at 1 rad/s.

COMPARATIVE EXAMPLE 3

Blend of SOLEF 6008 VDF Homopolymer with di-isocyanate (D1) (6.5% by Weight of SOLEF 6008 VDF Homopolymer)

(18) The same procedure as detailed under Example 1 was followed, but blending the SOLEF 6008 VDF homopolymer with 6.5% by weight of SOLEF 6008 VDF homopolymer of the di-isocyanate (D1).

(19) FT-IR spectroscopic analyses showed no urethane peaks in the polymer so obtained. The SOLEF 6008 VDF homopolymer, free from hydroxyl groups, did not react with the di-isocyanate compound (D1) so that the resulting polymer was free from bridging groups comprising one or more urethane moieties.

(20) The polymer so obtained had a contact angle towards water of 87.1 degrees and a melt viscosity of 1000 Pa.Math.s at 1 rad/s.

EXAMPLE 5

Blend of Polymer (F3) with Di-Isocyanate (D1) (2.0% by Weight of Polymer (F3))

(21) The polymer (F3) (57.7 g) and the di-isocyanate (D1) (1.3 g) were blended at room temperature. The molar ratio between the acrylate groups in polymer (F3) and the isocyanate groups in di-isocyanate (D1) was 28:1.

(22) The mixture was then charged in a heating mixer and stirred (30 rpm) for 6 minutes at 210 C. The blend was finally discharged and cool down to room temperature.

(23) FT-IR spectroscopic analyses showed urethane peaks in the polyurethane fluoropolymer so obtained (1535 cm.sup.1).

(24) The polyurethane fluoropolymer had a contact angle towards water of 82.8 degrees and a melt viscosity of 60000 Pas at 1 rad/s.

COMPARATIVE EXAMPLE 4

(25) The polymer (F3), free from urethane moieties, had a contact angle towards water of 93.2 degrees and a melt viscosity of 9000 Pa.Math.s at 1 rad/s.

EXAMPLE 6

(26) 26.75 g (0.204 eq.) of 4,4-methylenebis(cyclohexylisocyanate), 90 g of a 10% by weight polymer (F2) solution in acetone (0.134 eq. of polymer (F2)) and 1 g of 1,4-butylenediamine were dispersed and mixed with a magnetic stirrer at room temperature. After 20 minutes, a viscous and opalescent composition was obtained which was poured into a tray and put into an oven at 50 C. for 3 hours. Then the oven temperature was raised up to 100 C. for 4 hours, and subsequently at 150 C. for 30 minutes. The polymer slab was thoroughly washed with ethyl acetate until the solvent was clear. The slab was put again in the oven at 100 C. for 1 hour to remove residual solvent.

(27) The polyurethane fluoropolymer so obtained contained 34% by weight of recurring units derived from polymer (F2) and 66% by weight of polyurethane recurring units.

(28) FT-IR spectroscopic analysis showed urethane peaks in the polyurethane fluoropolymer in the range 1690-1710 cm.sup.1.

(29) The polyurethane fluoropolymer so obtained had a contact angle towards hexadecane of 40 degrees and a char yield of about 30% at 550 C.

(30) The amount of insolubles in DMF of the polyurethane fluoropolymer so obtained was about 75% by weight.

COMPARATIVE EXAMPLE 5

(31) The polymer (F2), free from urethane moieties, was soluble in DMF.

EXAMPLE 7

(32) The same procedure as detailed under Example 6 was followed, but dispersing and mixing with a magnetic stirrer at room temperature 40.26 g (0.307 eq.) g of 4,4-methylenebis(cyclohexylisocyanate), 7.15 g of a 10% by weight polymer (F2) solution in acetone (0.011 eq. of polymer (F2)), 8.38 g (0.270 eq.) of 1,2-ethanediol and 1 g of 1,4-butylenediamine.

(33) The polyurethane fluoropolymer so obtained contained 1.6% by weight of recurring units derived from polymer (F2) and 98.4% by weight of polyurethane recurring units.

(34) FT-IR spectroscopic analysis showed urethane peaks in the polyurethane fluoropolymer in the range 1690-1710 cm.sup.1.

(35) The polyurethane fluoropolymer so obtained had a contact angle towards hexadecane of 29 degrees.

COMPARATIVE EXAMPLE 6

(36) The same procedure as detailed under Example 6 was followed, but dispersing and mixing with a magnetic stirrer at room temperature 40.13 g (0.306 eq.) g of 4,4-methylenebis(cyclohexylisocyanate), 8.87 g (0.286 eq.) of 1,2-ethanediol and 1 g of 1,4-butylenediamine.

(37) FT-IR spectroscopic analysis showed urethane peaks in the polyurethane polymer in the range 1690-1710 cm.sup.1.

(38) The polyurethane polymer so obtained, free from fluorinated blocks, had a contact angle towards hexadecane of 0 degrees and a char yield of 0% at 550 C.

EXAMPLE 8

Blend of Polymer (F1) (92.97% by Weight) with Di-Isocyanate (D2) (7.00% by Weight) and 1,2-Ethanediol (0.03% by Weight)

(39) The same procedure as detailed under Example 1 was followed, but blending the polymer (F1) (92.97% by weight) with di-isocyanate (D2) (7.00% by weight) and 1,2-ethanediol (0.03% by weight).

EXAMPLE 9

Blend of Polymer (F1) (95.16% by Weight) with Di-Isocyanate (D2) (1.00% by Weight) and PEO-1 (3.84% by Weight)

(40) The same procedure as detailed under Example 1 was followed, but blending the polymer (F1) (95.16% by weight) with di-isocyanate (D2) (1.00% by weight) and PEO-1 (3.84% by weight).

EXAMPLE 10

Blend of Polymer (F1) (95.16% by Weight) with Di-Isocyanate (D2) (1.00% by Weight) and PEO-2 (3.84% by Weight)

(41) The same procedure as detailed under Example 1 was followed, but blending the polymer (F1) (95.16% by weight) with di-isocyanate (D2) (1.00% by weight) and PEO-2 (3.84% by weight).

EXAMPLE 11

Manufacture of a Membrane

(42) A blend of the pellets obtained in Example 8 (30% by weight) and SOLEF 1015 PVDF homopolymer powder (70% by weight) were dissolved in NMP reaching a solution concentration of 14% by weight. This solution was then casted to form a film in an Elcometer 4340 film applicator which was later put in a water bath at room temperature. The porous membrane had a porosity of 86% and the water flow was 890 L/hm.sup.2.

COMPARATIVE EXAMPLE 7

Manufacture of a Membrane

(43) The same procedure as detailed under Example 11 was followed, but using only SOLEF 1015 PVDF homopolymer powder. The porous membrane had a porosity of 83% and the water flow was 112 L/hm.sup.2.

(44) It has been thus shown that the membrane obtained by using the polyurethane fluoropolymer of the invention is advantageously more hydrophilic than standard membranes obtained by using pure fluoropolymers.