Cross-linkable adhesive compound with hard and soft blocks as a permeant barrier

• US 9,487,684 B2
• Filed: 03/25/2013
• Issued: 11/08/2016
• Est. Priority Date: 04/17/2012
• Status: Active Grant

• Current Assignee: Tesa SE (Maxingvest AG)
• Original Assignee: Tesa SE (Maxingvest AG)
• Inventors: Krawinkel, Thorsten, Keite-Telgenbsher, Klaus, Grnauer, Judith, Ellinger, Jan
• Primary Examiner(s): HARLAN, ROBERT D
• Application Number:
  US14/389,596
• Publication Number:
  US 20150079389A1
• Time in Patent Office: 1,324 Days
• US Class Current: 1/1
• CPC Class Codes: C08F 8/36 Sulfonation; Sulfation
• CPC Class Codes: C08K 5/0091 Complexes with metal-heteroatom-bonds
• CPC Class Codes: C08K 5/07 Aldehydes; Ketones
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 53/025 modified
• CPC Class Codes: C08L 91/00 Compositions of oils, fats or waxes; Compositions of derivatives thereof
• CPC Class Codes: C09J 11/06 organic
• CPC Class Codes: C09J 153/00 Adhesives based on block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers
• CPC Class Codes: C09J 153/025 modified
• CPC Class Codes: C09J 193/04 Rosin
• CPC Class Codes: C09J 2203/318 for the production of liquid crystal displays
• CPC Class Codes: C09J 2453/00 Presence of block copolymer
• CPC Class Codes: C09J 5/02 involving pretreatment of the surfaces to be joined
• CPC Class Codes: C09J 5/06 involving heating of the applied adhesive
• CPC Class Codes: C09J 7/20 characterised by their carriers
• CPC Class Codes: C09J 7/35 Heat-activated
• CPC Class Codes: C09J 7/387 Block-copolymers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: Y10T 428/2852 : Adhesive compositions

Abstract

Adhesive compound as a permeant barrier, comprising (i) block copolymers having a construction A-B-A, (A-B)_n, (A-B)_nX, or (A-B-A)_nX, where X is the radical of the coupling reagent, n is a whole number between 2 and 10, A is a polymer made of a vinyl aromatic compound and B is a polymer block made of an alkene or diene, wherein this polymer block can also be hydrated, with the condition that at least part of the A blocks is sulfonated, optionally with two-block copolymers in the form of A-B as an admixture component, and (ii) at least one tackifier resin.

Claims

1. An adhesive comprised of

(i) block copolymers and also mixtures thereof, having an A-B-A, (A-B)_nX, or (A-B-A)_nX construction, where X is the radical of a coupling reagent, n is an integer between 2 and 10, A is a polymer block of a vinylaromatic, and B is a polymer block of an alkene or diene, and where the A blocks are sulfonated to the extent of 0.5 to 50 mol %, based on the total monomer units of the A blocks, and diblock copolymers of the form A-B optionally as admixture component, and

(ii) at least one tackifier resin.

2. The adhesive as claimed in claim 1, wherein B is a hydrogenated polymer block of an alkene or diene.

3. The adhesive as claimed in claim 1 wherein 0.5 to 50 mol % of the block copolymers are in the form of sulfonated copolymers and have sulfonated A blocks, the aromatic moieties of which are sulfonated to an extent of 0.5 to 20 mol % per mole of the monomer unit, based on the total monomer units of the A blocks in the sulfonated copolymer.

4. The adhesive as claimed in claim 1, further comprising (iii) at least one metal complex with a substitutable complexing agent.

5. The adhesive as claimed in claim 1, wherein the admixture component is a diblock copolymer of the form A-B, a copolymer with polymer blocks A′

of vinylaromatics and polymer blocks B′

of an alkene or diene.

6. The adhesive as claimed in claim 1, wherein (i) the A blocks each independently have a T_g of more than 40°

C. and the B blocks each independently have a T_g of less than 0°

C.

7. The adhesive as claimed in claim 1, wherein the B blocks independently are homopolymers or copolymers of monomers selected from the group consisting of ethylene, propylene and 1,3-dienes.

8. The adhesive as claimed in claim 1, wherein the B blocks are at least partially hydrogenated.

9. The adhesive as claimed in claim 1, wherein the A blocks independently are homopolymers or copolymers of monomers of at least one vinylaromatic.

10. The adhesive as claimed in claim 1, wherein the metal complex with a substitutable complexing agent corresponds to a metal chelate of the formula I,

(R¹O)_nM(XR²Y)_m 

 

(I)

where M is a metal selected from the group consisting of metals of main groups 2, 3, 4, and 5 of the Periodic Table of the Elements and from the transition metals, and R¹ is an alkyl or aryl group,

n is 0 or a larger integer

X and Y in the chelate ligand (XR²Y) independently are oxygen or nitrogen, which are optionally bonded to R² by a double bond,

R² is an alkylene group which joins X and Y and which is linear or branched, and optionally has heteroatom(s) in the alkylene group, nitrogen, or sulfur;

m is an integer, but is at least 1.

11. The adhesive as claimed in claim 10, wherein the chelate ligand in the metal chelate is formed from the reaction of at least one of the compounds selected from the group consisting of triethanolamine, 2,4-pentanedione, 2-ethyl-1,3-hexanediol and lactic acid.

12. The adhesive as claimed in claim 1, wherein the overall composition of the adhesive contains

(ii) at 10 to 70 wt %, at least one tackifier resin, and/or an epoxy resin, and

(iii) at least one metal complex with a substitutable complexing agent, and optionally

(iv) up to 20 wt %, a plasticizer, and

(v) 0.0 to 20 wt %, fillers, additives, photoinitiators, accelerators and/or curing agents,

(vi) up to 60 wt %, a reactive resin, and

(i) the block copolymers and/or mixtures comprising them, to 100 wt %.

13. The adhesive as claimed in claim 8, wherein the fraction in wt % of the vinylaromatics of the A blocks in the (i) copolymer in relation to the overall composition of the adhesive is at least 20 to 85 wt %.

14. The adhesive as claimed in claim 1, wherein the molar ratio of the sulfonic acid groups in the (i) sulfonated copolymer to the ligand (XR²Y) in the (iii) metal complex of the formula I is in the range from 1:

3 to 3;

1, with a fluctuation range of plus/minus 0.5.

15. The adhesive as claimed in claim 1, having a SAFT of greater than or equal to 150°

C.

16. The adhesive as claimed in claim 1, comprising as tackifier resins at least one hydrogenated hydrocarbon resin.

17. The adhesive as claimed in claim 1, comprising an epoxy resin, an acrylate and/or a methacrylate, and wherein the adhesive, optionally together with at least one reactive resin, comprises at least one photoinitiator absorbing UV light below 350 nm.

18. The adhesive as claimed in claim 1, wherein the chelate-crosslinked adhesive has a WVTR of less than or equal to 100 g/m²·

d, and/or the chelate-crosslinked adhesive has an OTR of less than or equal to 3000 g/m²·

d·

bar.

19. The adhesive as claimed in claim 1, said adhesive being a pressure-sensitive adhesive or a hotmelt adhesive.

23. A method for applying the adhesive of claim 1 to an element, wherein the adhesive is partially crosslinked prior to application or is partially crosslinked or crosslinked to completion after application, by heating of the adhesive and/or of the element before, during, or after the application of the adhesive to the element.

24. The method of claim 23, wherein the adhesive is thermally partially crosslinked prior to an application, and following the application, crosslinking to completion is accomplished thermally and/or with UV light after the application.

25. An adhesive assembly for formation of temperature-stable barrier layers, having a SAFT of greater than or equal to 180°

C., for preventing the diffusion of permeants, for encapsulating an electronic arrangement, or for encapsulating an optoelectronic arrangement, wherein said assembly comprises the adhesive of claim 1.

26. A sheetlike bonding means comprising the adhesive of claim 1, the sheetlike bonding means being a sheetlike element of the adhesive or an adhesive tape, the adhesive tape having a carrier and, on at least one side of the carrier, the applied adhesive, and the adhesive of the sheetlike bonding means being substantially dried.

20. A process for producing an adhesive which comprises mixing

(i) block copolymers and also mixtures thereof, having an A-B-A, (A-B)_nX, or (A-B-A)_nX construction, where X is the radical of a coupling reagent, n is an integer between 2 and 10, A is a polymer block of a vinylaromatic, and B is a polymer block of an alkene or diene, this polymer block being hydrogenated, with the proviso that at least some of the A blocks are sulfonated, and diblock copolymers of the form A-B, optionally, as admixture component, and

(ii) at least one tackifier resin.

21. The process for producing an adhesive as claimed in claim 20, wherein additionally

(iii) at least one metal complex with a substitutable complexing agent and optionally as (ii) tackifier resin a substantially fully hydrogenated hydrocarbon resin, (iv) a plasticizer, and optionally (v) a filler, additive, accelerator, photoinitiator and/or optionally (vi) a reactive resin, together with at least one photoinitiator, are added.

22. An adhesive obtainable by a process according to claim 20.