Two component (epoxy/amine) structural foam-in-place material

• US 20050020703A1
• Filed: 08/11/2004
• Published: 01/27/2005
• Est. Priority Date: 05/02/2001
• Status: Abandoned Application

• Current Assignee: L&L Products Inc.
• Original Assignee: L&L Products Inc.
• Inventors: Kosal, David J., Czaplicki, Michael J., Madaus, Keith
• Application Number:
  US10/916,103
• Publication Number:
  US 20050020703A1
• Time in Patent Office: Days
• US Class Current: 521/82
• 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: Y10T 428/24372 Particulate matter
• CPC Class Codes: Y10T 428/24612 Composite web or sheet

Abstract

The present invention relates to methods, materials, and products for forming a foamed product, comprising the steps of combining an epoxy-based component with an amine-based component. The epoxy component is cross-linked through a polymerization reaction catalyzed by the amine formulation. In this regard, a reactive mixture or exothermic reaction is created between the epoxy component and the amine component when combined. The heat generated by the exothermic reaction softens a thermoplastic shell of a blowing agent formulated within the epoxy component thereby enabling a solvent core within the thermoplastic shell of the blowing agent to expand from the heat generated by the exothermic reaction.

Claims

1-19. -19. (canceled)

20. A method for producing a foamed article, comprising the steps of:

providing an epoxy component that includes;

i) an epoxy resin;

ii) a thixotropic additive;

iii) a reactive diluent;

iv) hollow glass microspheres; and

v) a blowing agent, the blowing agent being expandable microspheres;

providing a substantially liquid amine component that includes;

i) an aliphatic amine curing agent; and

ii) thixotropic additive;

combining and dispensing said epoxy component and said amine component to form a reactive mixture wherein;

i) the epoxy component and the amine component are formed as prior to forming the reactive mixture;

ii) the epoxy component and the amine component react together exothermically to produce heat;

iii) the admixture exhibits higher viscosity a zero shear rate and decreased viscosity at higher shear rate; and

iv) the heat causes the expandable microspheres to soften and expand;

providing the reactive mixture within an automotive body cavity contemporaneously with the formation of the mixture or shortly thereafter.

21. The method for producing a foamed article recited in claim 20, wherein said epoxy resin comprises from about 35% to about 95% by weight of said reactive mixture.

22. The method for producing a foamed article recited in claim 20, further including the step of combining said blowing agent of said epoxy component with an inert filler followed by combining said blowing agent of said epoxy component with said epoxy resin of said epoxy component.

23. The method for producing a foamed article recited in claim 20, wherein said reactive mixture further includes an additive selected form the group consisting of carbon black, ceramic microspheres, polymer particles, rubber particles, ceramic particles, inert mineral particles and combinations thereof.

24. The method for producing a foamed article recited in claim 20, wherein the thixotropic additive of the epoxy component is fumed silica.

25. The method of producing a foamed article recited in claim 21, wherein said cavity is at least partially provided by a component of an automotive vehicle selected from a rail member, a frame member, a door assembly, a rocker, a frame cross member, a vehicle window frame, a vehicle deck lid, a lift gate, a vehicle pillar assembly or a vehicle latch.

26. The method for producing a foamed article recited in claim 20, wherein the epoxy resin includes an ingredient selected from an epoxidated polyolefin, an epoxidated phenolic-novolac resin, a polyglycidyl ester, a glycidylether ester or a polyglycidyl ether.

27. The method for producing a foamed article recited in claim 26, wherein the epoxy component includes an ingredient selected from a liquid nitrile rubber, a clay or a pigment.

28. The method for producing a foamed article recited in claim 26, wherein amine component includes an ingredient selected from a liquid nitrile rubber or hollow glass microspheres.

29. A method for producing a foamed article, comprising the steps of:

providing an epoxy component that includes;

i) a bisphenol epoxy resin, the epoxy resin being from 35% to 99% by weight of the epoxy component;

ii) a thixotropic additive, the thixotropic additive being a fumed silica;

iii) an oxide;

iv) a reactive diluent;

v) liquid nitrile rubber;

vi) hollow glass microspheres;

vii) clay;

viii) a pigment; and

ix) a blowing agent, the blowing agent being expandable microspheres;

providing a substantially liquid amine component that includes;

i) an aliphatic amine curing agent;

ii) thixotropic additive including fumed silica or wollastonite; and

iii) rubber, the rubber being a liquid nitrile rubber;

combining and dispensing said epoxy component and said amine component at around room temperature to form a reactive mixture wherein;

i) the epoxy component and the amine component are formed prior to forming the reactive mixture;

ii) the epoxy component and the amine component react together exothermically to produce heat;

iii) the admixture exhibits higher viscosity a zero shear rate and decrease viscosity at higher shear rate; and

iv) the heat causes the expandable microspheres to soften and expand without addition of external heat;

providing the reactive mixture within an automotive body cavity contemporaneously with the formation of the mixture or shortly thereafter; and

allowing the reactive mixture to cure to form said foamed article.

30. The method for producing a foamed article recited in claim 29, wherein said epoxy resin comprises from about 35% to about 95% by weight of said reactive mixture.

31. The method for producing a foamed article recited in claim 29, wherein said epoxy resin and said thixotropic additive of said epoxy component are combined prior to adding said blowing agent to the epoxy component.

32. The method for producing a foamed article recited in claim 31, further including the step of combining said blowing agent of said epoxy component with an inert filler prior to combining said blowing agent of said epoxy component with said epoxy resin of said epoxy component and said thixotropic additive.

33. The method for producing a foamed article recited in claim 29, wherein the oxide is a calcium oxide and the reactive diluent is a glycidyl ether.

34. The method for producing a foamed article recited in claim 29, wherein the epoxy resin includes a chemical selected from an epoxidated polyolefin, an epoxidated phenolic-novolac resin, a polyglycidyl ester, a glycidylether ester or a polyglycidyl ether.

35. The method for producing a foamed article recited in claim 29, wherein the foamed article has a glass transition temperature greater than 200°

F.

36. A method for producing a foamed article, comprising the steps of:

providing a substantially liquid epoxy component that includes;

i) an epoxy resin, the epoxy resin being a glycidyl ether of bisphenol A, the epoxy resin being from 65% to 98% by weight of the epoxy component;

ii) a thixotropic additive, the thixotropic additive being a fumed silica;

iii) calcium oxide;

iv) a reactive diluent, the diluent being a glycidyl ether;

v) liquid nitrile rubber;

vi) hollow glass microspheres;

vii) clay;

viii) a pigment; and

ix) a blowing agent, the blowing agent being expandable microspheres formed of thermoplastic shells filled with a solvent core;

providing a substantially liquid amine component that includes;

i) an aliphatic amine curing agent;

ii) thixotropic additive including fumed silica and wollastonite;

iii) hollow glass microspheres; and

iv) rubber, the rubber being a liquid nitrile rubber;

combining and dispensing said epoxy component and said amine component at around room temperature to form a reactive mixture wherein;

i) the epoxy component and the amine component are formed as separate liquids prior to forming the reactive mixture;

ii) the epoxy component and the amine component react together exothermically to produce heat;

iii) the admixture exhibits higher viscosity a zero shear rate and decrease viscosity at higher shear rate; and

iv) the heat causes the thermoplastic shell filled with a solvent core to soften and expand due to gas pressure from said solvent core without addition of external heat;

providing the reactive mixture within an automotive body cavity contemporaneously with the formation of the mixture or shortly thereafter; and

allowing the reactive mixture to cure to form said foamed article wherein said foamed article is capable of substantial plastic deformation after curing without substantial loss of strength modulus and wherein said foamed article has a glass transition temperature greater than 200°

F. after such plastic deformation.

37. The method of producing a foamed article recited in claim 36, wherein said cavity is at least partially provided by a component of an automotive vehicle selected from a rail member, a frame member, a door assembly, a rocker or a frame cross member.

38. The method of producing a foamed article recited in claim 36, wherein said cavity is at least partially provided by a component of an automotive vehicle selected from a vehicle window frame, a vehicle deck lid, a lift gate, a vehicle pillar assembly or a vehicle latch.

39. The method of producing a foamed article recited in claim 36, wherein said epoxy resin and said thixotropic additive of the epoxy component are combined prior to adding said blowing agent to the epoxy component.