Two component thermosettable compositions useful for producing structural reinforcing adhesives

• US 6,451,876 B1
• Filed: 10/10/2001
• Issued: 09/17/2002
• Est. Priority Date: 10/10/2000
• Status: Active Grant

• Current Assignee: Henkel AG & Co KGaA
• Original Assignee: Henkel Corporation (Henkel AG & Co KGaA)
• Inventors: Koshy, Vettithara C.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US09/974,459
• Publication Number:
  US 20020115736A1
• Time in Patent Office: 342 Days
• Field of Search: 521/54, 521/89, 521/94, 521/95, 521/140, 521/135, 521/178, 523/219
• US Class Current: 523/219
• CPC Class Codes: C08J 2363/00 Characterised by the use of epoxy resins; Derivatives of epoxy resins
• CPC Class Codes: C08J 9/32 from compositions containing microballoons, e.g. syntactic foams
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins

Abstract

A two part system for producing structural reinforcing adhesives is provided wherein one component containing epoxy resin is combined with a second component containing a specified curative system. An aliphatic polyamine, an amidoamine, an alcohol and an adduct of a polyamine and an epoxide are present in the curative system. When a thermally activated blowing agent is utilized, the resulting foam is remarkably uniform in cell structure and has improved strength and modulus. Hollow inorganic microspheres are employed to reduce the density of the thermoset produced from the two part system.

Claims

1. A two component system capable of being cured to provide a structural reinforcement adhesive, said two component system comprising Component A and Component B, wherein Component A comprises at least one epoxy resin and Component B comprises at least one aliphatic polyamine, at least one amidoamine, at least one alcohol, and at least one adduct of a polyamine and an epoxide, wherein at least one of Component A or Component B additionally comprises hollow inorganic microspheres.

2. The two component system of claim 1 wherein Component A comprises at least one epoxy resin which is a glycidyl ether of a polyhydric phenol.

3. The two component system of claim 1 wherein Component A additionally comprises at least one reactive diluent.

4. The two component system of claim 1 wherein Component A additionally comprises at least one rubber.

5. The two component system of claim 1 wherein Component B additionally comprises hollow glass microspheres.

6. The two component system of claim 1 wherein Component A additionally comprises at least one thixotropic agent.

7. The two component system of claim 1 wherein Component A additionally comprises at least one blowing agent.

8. The two component system of claim 1 wherein Component A additionally comprises expandable microspheres.

9. The two component system of claim 1 wherein Component B additionally comprises at least one rubber.

10. The two component system of claim 1 wherein Component B additionally comprises at least one thixotropic agent.

11. The two component system of claim 1 wherein the weight ratio of Component A to Component B is selected such that the equivalent ratio of epoxy:

amine is from about 0.5;

1 to about 1;

0.5.

12. A two component system capable of being expanded and cured to provide a structural reinforcement foam, said two component system comprising Component A and Component B, wherein Component A comprises:

at least one epoxy resin which is a glycidyl ether of a polyhydric phenol;

at least one reactive diluent;

at least one rubber;

hollow inorganic microspheres;

at least one thixotropic agent; and

expandable microspheres;

and Component B comprises;

at least one aliphatic polyamine;

at least one amidoamine;

at least one alcohol;

at least one adduct of a polyamine and an epoxide;

at least one rubber;

at least one thixotropic agent; and

hollow inorganic microspheres.

13. The two component system of claim 12 wherein Component A comprises at least one epoxy resin which is a diglycidyl ether of bisphenol A.

14. The two component system of claim 12 wherein at least one reactive diluent is a mono glycidylether of a phenol.

15. The two component system of claim 12 wherein at least one rubber is a nitrile rubber.

16. The two component system of claim 12 wherein the hollow glass microspheres have a crush strength of at least about 2000 psi.

17. The two component system of claim 12 wherein at least one thixotropic agent is fumed silica.

18. The two component system of claim 12 wherein at least one thixotropic agent is hydrophobic fumed silica.

19. The two component system of claim 12 wherein at least one aliphatic polyamine corresponds to the generic structure

wherein n=1-6.

20. The two component system of claim 12 wherein at least one amidoamine is an aliphatic amidoamine prepared by reacting an aliphatic polyamine with a fatty acid.

21. The two component system of claim 12 wherein at least one alcohol is an aromatic alcohol.

22. The two component system of claim 12 wherein at least one alcohol is a polyhydric phenol.

23. The two component system of claim 12 wherein at least one alcohol is bisphenol A.

24. The two component system of claim 12 wherein at least one adduct is an adduct of an aliphatic polyamine corresponding to the general structure

wherein n=1-6.

25. The two component system of claim 12 wherein at least one adduct is an adduct of a glycidyl ester.

26. The two component system of claim 12 wherein at least one adduct is an adduct of a glycidyl ester of a C₂-C₂₄ aliphatic carboxylic acid.

27. The two component system of claim 12 wherein Component A has the following composition:

28. The two component system of claim 12 wherein Component B has the following composition:

29. The two component system of claim 12 wherein one or both of Component A and Component B additionally comprise at least one filler.

30. The two component system of claim 12 wherein one or both of Component A and Component B additionally comprise at least one filler selected from the group consisting of clays, wollastonite, and calcium oxide.

31. The two component system of claim 12 wherein at least one adduct is an adduct of a glycidyl ester of a C₆-C₂₂ alpha-alkylalkane monocarboxylic acid.

32. The two component system of claim 12 wherein at least one adduct is an adduct of an aliphatic polyamine containing at least two amine groups selected from the group consisting of primary amine groups, secondary amine groups, and combinations thereof.

33. The two component system of claim 12 wherein at least one adduct contains one or more amine groups which are not reacted with epoxide.

34. A method of curing a thermosettable composition comprised of at least one epoxy resin and hollow glass microspheres, said method comprising combining said thermosettable composition with a curative system comprising

(a) at least one aliphatic polyamine;

(b) at least one amidoamine;

(c) at least one alcohol; and

(d) at least one adduct of an aliphatic polyamine and an epoxide;

and initiating exothermic reaction of the thermosettable composition and the curative system.

35. A method of preparing a structural reinforcing foam comprising combining a thermosettable expandable composition comprised of

(a) at least one epoxy resin which is a glycidyl ether of a polyhydric phenol;

(b) at least one reactive diluent;

(c) at least one rubber;

(d) hollow glass microspheres;

(e) at least one thixotropic agent; and

(f) expandable microspheres;

with a curative system comprising

(a) at least one aliphatic polyamine;

(b) at least one amidoamine;

(c) at least one alcohol; and

(d) at least one adduct of an aliphatic polyamine and an epoxide

and initiating exothermic reaction of the thermosettable composition and the curative system and expansion of the expandable microspheres.

36. A method of reinforcing a substrate having a surface, said method comprising combining at least one epoxy resin, hollow glass microspheres, and a curative system comprised of at least one aliphatic polyamine, at least one amidoamine, at least one alcohol, and at least one adduct of a polyamine and an epoxide to form a mixture, applying said mixture to said surface, and curing said mixture.

37. A method of reinforcing a structural member having a cavity, said method comprising:

(A) combining

(i) at least one epoxy resin which is a glycidyl ether of a polyhydric phenol;

(ii) at least one reactive diluent;

(iii) at least one rubber;

(iv) hollow glass microspheres;

(v) at least one thixotropic agent;

(vi) expandable microspheres; and

(vii) a curative system comprised of

(a) at least one aliphatic polyamine;

(b) at least one amidoamine;

(c) at least one alcohol; and

(d) at least one adduct of a polyamine and an epoxide;

to form a pumpable mixture;

(B) introducing said pumpable mixture into said cavity; and

(C) curing and expanding said pumpable mixture to provide a structural reinforcement foam within said cavity.

38. A structural reinforcement adhesive which is the reaction product of at least one epoxy resin, hollow glass microspheres, and a curative system comprising at least one aliphatic polyamine, at least one amidoamine, at least one alcohol, and at least one adduct of an aliphatic polyamine and an epoxide.

39. A structural reinforcement foam which is the reaction product of:

(a) at least one epoxy resin which is a glycidyl ether of a polyhydric phenol;

(b) at least one reactive diluent;

(c) at least one nitrile rubber;

(d) hollow glass microspheres;

(e) at least one thixotropic agent;

(f) expandable microspheres; and

(g) a curative system comprising

(i) at least one aliphatic polyamine;

(ii) at least one amidoamine;

(iii) at least one alcohol; and

(iv) at least one adduct of an aliphatic polyamine and an epoxide.

40. A component useful in curing a second component comprised of epoxy resin, said component comprising at least one aliphatic polyamine, at least one amidoamine, at least one alcohol, and at least one adduct of polyamine and an epoxide.

41. The component of claim 40, wherein said component additionally comprises hollow glass microspheres.

42. The component of claim 40, wherein said component additionally comprises at least one rubber.

43. The component of claim 40, wherein said component additionally comprises at least one thixotropic agent.

44. The component of claim 40, wherein said component additionally comprises hollow glass microspheres, at least one rubber and at least one thixotropic agent.

45. The component of claim 40, wherein at least one aliphatic polyamine corresponds to the generic structure

wherein n=1-6.

46. The component of claim 40, wherein at least one amidoamine is an aliphatic amidoamine prepared by reacting an aliphatic polyamine with a fatty acid.

47. The component of claim 40, wherein at least one alcohol is an aromatic alcohol.

48. The component of claim 40, wherein at least one alcohol is a polyhydric phenol.

49. The component of claim 40, wherein at least one alcohol is bisphenol A.

50. The component of claim 40, wherein at least one adduct is an adduct of an aliphatic polyamine corresponding to the general structure

wherein n=1-.

51. The component of claim 40, wherein at least one adduct is an adduct of a glycidyl ester.

52. The component of claim 40, wherein at least one adduct is an adduct of a glycidyl ester of a C₂-C₂₄ aliphaticcarboxylic acid.

53. A component useful in curing a second component comprised of an epoxy resin, said component comprising:

a) a first aliphatic polyamine corresponding to the generic structure of

wherein n=1-6.

b) an aliphatic amidoamine prepared by reacting a second aliphatic polyamine, which may be the same as or different from the first aliphatic polyamine, with a fatty acid;

c) an aromatic alcohol;

d) an adduct of a polyamine and a glycidyl ester of a C₂-C₂₄ aliphatic carboxylic acid; and

e) at least one additive selected from the group consisting of rubbers, thixotropic agents and hollow glass microspheres.

54. The component of claim 53 wherein said component comprises at least two additives selected from the group consisting of rubbers, thixotropic agents and hollow glass microspheres.

55. The component of claim 53 wherein said component comprises at least one rubber, at least one thixotropic agent and hollow glass microspheres.