Elastic, moisture-vapor permeable films, their preparation and their use

• US 9,394,414 B2
• Filed: 09/29/2010
• Issued: 07/19/2016
• Est. Priority Date: 09/29/2010
• Status: Active Grant

• Current Assignee: Kraton Polymers US LLC (DL Holdings Co., Ltd.)
• Original Assignee: Kraton Polymers US LLC (DL Holdings Co., Ltd.)
• Inventors: Schroeder, Todd, Flood, John, Blackwell, Richard, Ehrlich, Martin, Gumulka, Jerzy
• Primary Examiner(s): Chriss, Jennifer
• Assistant Examiner(s): THOMPSON, CAMIE S
• Application Number:
  US12/893,145
• Publication Number:
  US 20120077400A1
• Time in Patent Office: 2,120 Days
• Field of Search: 525/89
• US Class Current: 1/1
• CPC Class Codes: B01D 53/228 characterised by specific membranes
• CPC Class Codes: B01D 53/268 by diffusion
• CPC Class Codes: B01D 69/1071 Woven, non-woven or net mesh
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 69/1213 Laminated layers
• CPC Class Codes: B01D 71/26 Polyalkenes
• CPC Class Codes: B01D 71/261 Polyethylene
• CPC Class Codes: B01D 71/28 Polymers of vinyl aromatic compounds
• CPC Class Codes: B01D 71/281 Polystyrene
• CPC Class Codes: B01D 71/82 characterised by the presence of specified groups, e.g. introduced by chemical after-treatment
• CPC Class Codes: B32B 2255/102 synthetic resin or rubber layer being a foamed layer
• CPC Class Codes: B32B 2260/046 Synthetic resin
• CPC Class Codes: B32B 2307/51 Elastic
• CPC Class Codes: B32B 2307/724 Permeability to gases, adsorption
• CPC Class Codes: B32B 2307/7265 Non-permeable
• CPC Class Codes: B32B 2437/00 Clothing anti-ballistic clothing B32B2571/02
• CPC Class Codes: B32B 2535/00 Medical equipment, e.g. bandage, prostheses, catheter medical patches B32B2556/00
• CPC Class Codes: B32B 27/00 Layered products comprising a layer of synthetic resin fibrous or filamentary layer made of a synthetic resin B32B5/02; particulate layer made of a synthetic resin B32B5/16; foamed layer made of a synthetic resin B32B5/18
• CPC Class Codes: B32B 27/12 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 27/28 comprising synthetic resins not wholly covered by any one of the sub-groups B32B27/30 - B32B27/42
• CPC Class Codes: B32B 27/302 : comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers
• CPC Class Codes: B32B 5/245 : another layer next to it being a foam layer
• CPC Class Codes: C08F 297/046 : polymerising vinyl aromatic monomers and isoprene, optionally with other conjugated dienes
• CPC Class Codes: C08F 8/04 : Reduction, e.g. hydrogenation
• CPC Class Codes: C08F 8/36 : Sulfonation; Sulfation
• CPC Class Codes: C08J 2353/02 : of vinyl aromatic monomers and conjugated dienes
• CPC Class Codes: C08J 5/18 : Manufacture of films or sheets
• CPC Class Codes: C08L 2205/02 : containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 2205/025 : containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• CPC Class Codes: C08L 53/02 : of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: C08L 53/025 : modified
• CPC Class Codes: C09D 153/025 : modified
• CPC Class Codes: Y10T 442/2139 : Coating or impregnation specified as porous or permeable to a specific substance [e.g., water vapor, air, etc.]

Abstract

The present disclosure relates to films such as membranes and coatings and to coated articles. The films comprise a combination of at least one elastomeric styrenic block copolymer which is optionally functionalized with functional groups different from sulfonic acid or sulfonate ester functional groups, and at least one sulfonated block copolymer. Films comprising the optionally functionalized block copolymer(s) and the additional sulfonated block copolymer(s) are elastic and are moisture-vapor permeable, and thus useful as coatings in breathable clothing and footwear, industrial workwear including cleanroom coveralls, in medical applications such as wound dressings and protective clothing, for bed sheets and mattress or seat covers, and other non-apparel applications.

Claims

1. A film comprising

a) at least one elastomeric styrenic block copolymer which is optionally functionalized with functional groups different from sulfonic acid or sulfonate ester functional groups,

b) at least one sulfonated block copolymer having at least one end block A and at least one interior block B wherein each A block contains essentially no sulfonic acid or sulfonate ester functional groups and each B block is a polymer block containing from about 10 to about 100 mol % sulfonic acid or sulfonate ester functional groups based on the number of sulfonation susceptible monomer units of the B block, and

wherein (a) and (b) are present in weight a ratio of from about 0.1:

1 to about 10;

1.

2. The film of claim 1, wherein the ratio of (a) to (b) is from about 0.5:

1 to about 5;

1.

3. The film of claim 1, wherein the styrenic block copolymer (a) has a general configuration A-B, A-B-A, (A-B)_n, (A-B-A)_n, (A-B-A)_nX, (A-B)_nX or a mixture thereof, wherein n is an integer from about 2 to about 30, and X is the residue of a coupling agent, each A block independently is a polymer block of one or more alkenyl arenes having a number average molecular weight of from 3,000 to 60,000;

and

each B block independently is a polymer block of one or more conjugated dienes and from 0to about 75%-wt. of one or more alkenyl arenes, which block contains no significant levels of olefinic unsaturation and has a number average molecular weight of from 10,000 to 300,000;

wherein the total amount of alkenyl arenes in the block copolymer (a) is from about 2 to about 75%-wt.

4. The film of claim 3, wherein the total amount of alkenyl arenes in the styrenic block copolymer (a) is from about 5 to about 65%-wt.

5. The film of claim 1 wherein the styrenic block copolymer component (a) comprises at least one S-E/B-S or S-E/P-S block copolymer which is optionally functionalized.

6. The film of claim 1 wherein the styrenic block copolymer component (a) consists of one or more non-functionalized styrenic block copolymers.

7. The film of claim 1 wherein the styrenic block copolymer component (a) consists of one or more functionalized styrenic block copolymers.

8. The film of claim 1 wherein the styrenic block copolymer component (a) consists of one or more functionalized styrenic block copolymers and one or more non-functionalized styrenic block copolymers.

9. The film of claim 1, wherein the sulfonated block copolymer (b) has a general configuration A-B-A, A-B-A-B-A, (A-B-A)_nX, (A-B)_nX, A-D-B-D-A, A-B-D-B-A, (A-D-B)_nX, (A-B-D)_nX or mixtures thereof, where n is an integer from 2 to about 30, and X is a coupling agent residue and wherein each D block is a polymer block resistant to sulfonation and the plurality of A blocks, B blocks, or D blocks are the same or different.

10. The film of claim 9, wherein each D block of the sulfonated block copolymer (b) is selected from the group consisting of (i) a polymerized or copolymerized conjugated diene selected from isoprene, 1,3-butadiene having a vinyl content prior to hydrogenation of between 20 and 80 mol percent, (ii) a polymerized acrylate monomer, (iii) a silicon polymer, (iv) polymerized isobutylene and (v) mixtures thereof, wherein any segments containing polymerized 1,3-butadiene or isoprene are subsequently hydrogenated.

11. The film of claim 1, having no more than 50% set at 50% elongation.

12. The film of claim 1, having a moisture vapor transmission rate of at least 1,000 g/m²/day as measured by the procedure described herein.

13. The film of claim 1, wherein (a) and (b) are present in weight a ratio of from about 7:

3 to 3;

7.

14. A coated article comprising a substrate and a coating comprising

a) at least one styrenic block copolymer which is optionally functionalized with functional groups different from sulfonic acid or sulfonate ester functional groups,

b) at least one sulfonated block copolymer having at least one end block A and at least one interior block B wherein each A block contains essentially no sulfonic acid or sulfonate ester functional groups and each B block is a polymer block containing from about 10 to about 100 mol % sulfonic acid or sulfonate ester functional groups based on the number of sulfonation susceptible monomer units of the B block, and

wherein (a) and (b) are present in weight a ratio of from about 0.1:

1 to about 10;

1.

15. The coated article of claim 14, wherein the substrate is a natural or synthetic, woven and non-woven material, or a mixture thereof.

16. The coated article of claim 14, wherein the substrate is flexible or elastic.

17. The coated article of claim 14 wherein the styrenic block copolymer component (a) consists of one or more non-functionalized styrenic block copolymers.

18. The coated article of claim 14, wherein (a) and (b) are present in weight a ratio of from about 7:

3 to 3;

7.

19. An elastic membrane comprising

a) at least one styrenic block copolymer which is optionally functionalized with functional groups different from sulfonic acid or sulfonate ester functional groups,

b) at least one sulfonated block copolymer having at least one end block A and at least one interior block B wherein each A block contains essentially no sulfonic acid or sulfonate ester functional groups and each B block is a polymer block containing from about 10 to about 100 mol % sulfonic acid or sulfonate ester functional groups based on the number of sulfonation susceptible monomer units of the B block, and

wherein (a) and (b) are present in weight a ratio of from about 0.1:

1 to about 10;

1, having no more than 50% set at 50% elongation, and having a moisture vapor transmission rate of at least 1,000 g/m²/day as measured by the procedure described herein.

20. The elastic membrane of claim 19 wherein the styrenic block copolymer component (a) consists of one or more non-functionalized styrenic block copolymers.

21. The elastic membrane of claim 19, wherein (a) and (b) are present in weight a ratio of from about 7:

3 to 3;

7.

22. A coating or film-casting composition comprising a liquid phase and

a) at least one styrenic block copolymer which is optionally functionalized with functional groups different from sulfonic acid or sulfonate ester functional groups,

b) at least one sulfonated block copolymer having at least one end block A and at least one interior block B wherein each A block contains essentially no sulfonic acid or sulfonate ester functional groups and each B block is a polymer block containing from about 10 to about 100 mol % sulfonic acid or sulfonate ester functional groups based on the number of sulfonation susceptible monomer units of the B block, and

wherein (a) and (b) are present in weight a ratio of from about 0.1:

1 to about 10;

1.

23. The composition of claim 22, wherein the liquid phase comprises one or more organic solvents.

24. The composition of claim 23, wherein the liquid phase comprises one or more aprotic organic solvents.

25. The composition of claim 22 having a solids content of no more than 50%-wt.

26. The composition of claim 25, which is in form of an aqueous or non-aqueous dispersion.

27. The composition of claim 25, which is in form of a non-aqueous dispersion or solution.

28. The coating or film-casting composition of claim 22 wherein the styrenic block copolymer component (a) consists of one or more non-functionalized styrenic block copolymers.

29. The coating or film-casting composition of claim 22, wherein (a) and (b) are present in weight a ratio of from about 7:

3 to 3;

7.