Thermally conductive polyurethane adhesive composition

Patent metadata

Field	Value
Publication number	US-12398304-B2
Application number	US-202217804623-A
Country	US
Kind code	B2
Filing date	May 31, 2022
Priority date	Dec 13, 2019
Publication date	Aug 26, 2025
Grant date	Aug 26, 2025

Abstract

The present invention relates to a thermally conductive polyurethane adhesive composition having excellent mechanical properties as well as improved performance after aging and a method of manufacturing the same. Further, the present invention relates to method of manufacturing an article comprising the thermally conductive polyurethane adhesive composition and articles obtainable by the described method.

First claim

The invention claimed is:

1. A two-part composition comprising:
a component A comprising:
A1) a polyol;
A2) a chain extender; and
A3) a surface-treated thermally conductive inorganic filler with a surface having isocyanate-reactive groups; and

a component B comprising an isocyanate-terminated compound,
wherein an adhesive composition is obtained from a mixture of the component A and the component B.

2. The two-part composition according to claim 1 , wherein the polyol is a polyether polyol.

3. The two-part composition according to claim 1 , wherein the polyol has a molecular weight M n of from 700 to 12,000 g/mol.

4. The two-part composition according to claim 1 , wherein the chain extender is a diol selected from the group consisting of 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-prentanediol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, neopentyl glycol, polybutylene glycol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-bis(hydroxymethyl)cyclohexane, dimer diols, and mixtures thereof.

5. The two-part composition according to claim 1 , wherein the chain extender has a molecular weight M n of from 60 to 600 g/mol.

6. The two-part composition according to claim 1 , wherein the thermally conductive inorganic filler is selected from the group consisting of metal oxides, metal hydroxides, metal silicates, metal sulfides, and combinations thereof.

7. The two-part composition according to claim 1 , wherein the thermally conductive inorganic filler is selected from the group consisting of aluminum oxide, aluminum hydroxide, aluminum silicate, and combinations thereof.

8. The two-part composition according to claim 1 , wherein the isocyanate-reactive groups comprise an isocyanate-reactive group selected from the group consisting of hydroxyl, amino, carboxyl, thiol, epoxy group, and combinations thereof.

9. The two-part composition according to claim 1 , wherein the isocyanate-reactive groups comprise an isocyanate-reactive group that is a hydrolyzed residue of an aminoalkoxysilyl compound or epoxidized alkoxysilyl compound.

10. The two-part composition according to claim 1 , wherein:
the isocyanate-reactive groups comprise an isocyanate-reactive group that is a hydrolyzed residue of an epoxidized alkylsilyl compound, the aminoalkylsilyl compound selected from the group consisting of γ-glycidoxypropyltrimethoxysilyl, γ-glycidoxypropyltriethoxysilyl, γ-glycidoxypropylmethyldimethoxysilyl, and γ-glycidoxypropylmethyldiethoxysilyl, or
the isocyanate-reactive groups comprise an isocyanate-reactive group that is a hydrolyzed residue of an aminoalkylsilyl compound, the aminoalkylsilyl compound selected from the group consisting of aminoethyltrimethoxysilyl, aminoethyltriethoxysilyl, aminopropyltrimethoxysilyl, aminopropyltriethoxysilyl, aminopropylmethyldimethoxysilyl, aminopropylmethyldiethoxysilyl, aminoethyl-γ-aminopropyl-trimethoxysilyl, and iminobis(propyltrimethoxysilyl), or
combinations thereof.

11. The two-part composition according to claim 1 , wherein the isocyanate-terminated compound is an aliphatic or aromatic isocyanate-terminated compound.

12. The two-part composition according to claim 1 , wherein the isocyanate-terminated compound is a mixture of aromatic (poly) isocyanates and/or aromatic (poly) isocyanate prepolymers.

13. The two-part composition according to claim 1 , wherein the ratio by mass of components A and B is from 10:1 to 1:5.

14. The two-part composition according to claim 1 , wherein the surface-treated thermally conductive inorganic filler is present in an amount of from 10 wt. % to 90 wt. %, based on the total weight of component A.

15. The two-part composition according to claim 1 , wherein the polyol and the chain extender are present in the component A in a weight ratio of from 20:1 to 4:1.

16. The two-part composition according to claim 1 , wherein the ratio by mass of components A and B is of from 5:1 to 1:1.

17. A cured adhesive product obtained by:
mixing the component A and the component B of the two-part composition according to claim 1 to form an adhesive composition; and
curing the adhesive composition.

18. The cured adhesive product according to claim 17 , having a thermal conductivity of at least 0.8 W/mK, determined according to ISO 22007-2 at 25° C.

19. A method of manufacturing an article comprising:
providing a first substrate having a bonding surface;
providing a second substrate having a bonding surface;
providing the component A and the component B of the two-part composition of claim 1 ;
mixing the component A and the component B to obtain an adhesive composition;
applying the adhesive composition onto the bonding surface of the first substrate; and
bringing the bonding surface of the second substrate into contact with the adhesive composition on the bonding surface of the first substrate.

20. The method of manufacturing an article of claim 19 , further comprising curing the mixed adhesive disposed between the bonding surface of the first substrate and the bonding surface of the second substrate.

Assignees

• Henkel Ag & Co Kgaa

Inventors

• Zoeller Thomas
• Schlingloff Nicole
• Schmitz Eric
• Engels Thomas

Classifications

• C08K2003/2227

  of aluminium · CPC title

• C08G18/6674

  with compounds of group C08G18/3203 · CPC title

• C08G18/48

  Polyethers · CPC title

• C09J5/00

  Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers · CPC title

• C09J11/04

  inorganic · CPC title