Structural hot melt material and methods

• US 20030069335A1
• Filed: 09/04/2002
• Published: 04/10/2003
• Est. Priority Date: 09/07/2001
• Status: Active Grant

• Current Assignee: Zephyros, Inc.
• Original Assignee: L&L Products Inc.
• Inventors: Kosal, David J., Czaplicki, Michael J., Antrim, Jeanne
• Granted Patent: US 6,887,914 B2
• Time in Patent Office: Days
• US Class Current: 523/403
• CPC Class Codes: B62D 27/026 Connections by glue bonding in general F16B11/00; processes C09J5/00
• CPC Class Codes: C08J 2207/02 Adhesive
• CPC Class Codes: C08J 2363/00 Characterised by the use of epoxy resins; Derivatives of epoxy resins
• CPC Class Codes: C08J 9/0066 Use of inorganic compounding ingredients
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 63/00 Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
• CPC Class Codes: Y10T 156/1722 Means applying fluent adhesive or adhesive activator material between layers
• CPC Class Codes: Y10T 156/1724 At spaced areas
• CPC Class Codes: Y10T 428/2481 including layer of mechanically interengaged strands, strand-portions or strand-like strips
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249954 With chemically effective material or specified gas other than air, N, or carbon dioxide in void-containing component
• CPC Class Codes: Y10T 428/249958 Void-containing component is synthetic resin or natural rubbers
• CPC Class Codes: Y10T 428/249999 Differentially filled foam, filled plural layers, or filled layer with coat of filling material

Abstract

The present invention relates to a material, method, and application for reinforcement of structural members, especially joints such as a hem flange joint of an automobile. The method and material of the present invention comprises of combining, in parts by weight: less than about twenty percent (<20%) ethylene copolymer, less than about forty percent (<40%) epoxy, less than about thirty percent (<45%) epoxy-based resin, less than about two percent (<2%) blowing agent and from about one percent (1%) to about five percent (5%) curing agent (and optionally add any of the following components: less than about two percent (<2%) curing agent accelerator, from about twenty-five percent (25%) to fifty-five percent (55%) filler, and less than about one percent (<1%) of coloring agent). The application of the present invention comprises of: (1) providing a structural member having two substrates forming a space to be joined; (2) placing the material of the present invention in proximity of the space to be joined; (3) exposing the material to a heat source causing it to flow, fill, and cure in the defined area or space to be joined.

Claims

1. A material comprising of in parts by weight:

less than about twenty percent (<

20%) ethylene copolymer;

less than about forty percent (<

40%) epoxy;

less than about thirty percent (<

45%) epoxy-based resin;

less than about two percent (<

2%) blowing agent; and

from about one percent (1%) to about five percent (5%) curing agent.

2. The material of claim 1, further comprising, in parts by weight, less than about two percent (<

2%) curing agent accelerator.

3. The material of claim 2, wherein said curing agent accelerator is a modified urea.

4. The material of claim 1, further comprising, in parts by weight, from about twenty-five percent (25%) to fifty-five percent (55%) filler.

5. The material of claim 4, wherein said filler is selected from the group consisting of:

calcium carbonate, mica, montmorillinite, aramide pulp, nanoclay, fumed silica, and a combination thereof.

6. The material of claim 1, further comprising in parts by weight, less than about one percent (<

1%) coloring agent.

7. The material of claim 6, wherein said coloring agent is a metal oxide.

8. The material of claim 1, wherein said ethylene polymer is in a solid state and selected from the group consisting of:

ethylene-vinyl acrylate, ethylene-vinyl acetate, ethylene-methyl acrylate, ethylene-butyl acrylate, EMA/GMA, ethylene/α

-olefin, ethylene-ethyl acrylate, and a combination thereof.

9. The material of claim 1, wherein said epoxy is in a solid state and selected from a group consisting of:

bisphenol A, bisphenol F, novolac, modified urethane, and a combination thereof.

10. The material of claim 1, wherein said blowing agent is selected from the group consisting of azodiacarbonamide, p,p-Oxybisbenzene sulfonyl hydrazide, p-Toluene sulfonyl hydrazide, expancel, and a combination thereof.

11. The material of claim 1, wherein said curing agent is selected from the group consisting of cyanoguanidine, dicyanamide, imidazoles, and a combination thereof.

12. The material of claim 1, wherein said epoxy resin is comprised of less than about 75% epoxy resin in a solid state and less than about 25% epoxy resin in a liquid state.

13. The material of claim 12, wherein said epoxy resin in a solid state is bisphenol A resin.

14. The material of claim 12, wherein said epoxy resin in a liquid state is a epoxy phenol novolac resin

15. A material comprising of in parts by weight:

about 3.8 percent ethylene-methyl acrylate copolymer;

about 23.49 percent of an adduct of bisphenol A epoxy;

about 24.24 percent bisphenol A epoxy resin;

about 0.26 percent epoxy phenol novoiac resin;

about 0.12 percent azodicarbonamide;

about 0.5 percent methylene diphenyl bis;

about 1.55 percent cyanoguanidine;

about 45.84 percent calcium carbonate; and

about 0.19 percent metal oxide.

16. A method for forming a material for structural reinforcement comprising the steps of:

providing in parts by weight less than about twenty percent (<

20%) ethylene copolymer;

providing in parts by weight less than about forty percent (<

40%) epoxy;

providing in parts by weight less than about thirty percent (<

45%) epoxy-based resin;

providing in parts by weight less than about two percent (<

2%) blowing agent;

providing in parts by weight from about one percent (1%) to about five percent (5%) curing agent; and

combining said ethylene copolymer, said epoxy, said epoxy-based resin, said blowing agent, and said curing agent to form said material for structural reinforcement.

17. The method of claim 16, further comprising of at least one component selected from the group consisting of in parts by weight:

less than about two percent (<

2%) curing agent accelerator;

from about twenty-five percent (25%) to fifty-five percent (55%) filler;

less than about one percent (<

1%) coloring agent; and

a combination thereof.

18. A method of reinforcing structural members comprising the steps of:

providing a structural member having two substrates forming a space to be joined;

providing a material comprising of in parts by weight;

less than about twenty percent (<

20%) ethylene copolymer, less than about forty percent (<

40%) epoxy, less than about thirty percent (<

45%) epoxy-based resin, less than about two percent (<

2%) blowing agent and from about one percent (1%) to about five percent (5%) curing agent;

placing said material in proximity of said space to be joined;

exposing said material to a heat source causing said material to flow, fill, and cure in said space to be joined.

19. The method of claim 18, wherein said material is further comprised at least one component selected from the group consisting of in parts by weight:

less than about two percent (<

2%) curing agent accelerator;

from about twenty-five percent (25%) to fifty-five percent (55%) filler;

less than about one percent (<

1%) coloring agent; and

a combination thereof.

20. The method of claim 18, wherein said heat source exposes said material to a temperature of between about 285°

F. to about 400°

F.

21. The method of claim 19, wherein

said structural member having two substrates forming said space to be joined are a hem flange joint of an automobile, wherein said two substrates are cleaned, electrodeposition coated, and exposed to a heat source to form said hem flange joint;

said material is then placed in proximity of said space to be joined of said hem flange joint;

said ethylene polymer is about 3.8 percent ethylene-methyl acrylate copolymer;

said epoxy is about 23.49 percent bisphenol A epoxy;

said epoxy resin is comprised of about 24.24 percent bisphenol A epoxy resin and about 0.26 percent epoxy phenol novoiac resin;

said blowing agent is about 0.12 percent azodicarbonamide;

said curing agent is about 1.55 percent cyanoguanidine;

said curing agent accelerator is about 0.5 percent methylene diphenyl bis;

said filler is about 45.84 percent calcium carbonate;

said coloring agent is about 0.19 percent metal oxide; and

said heat source exposes said material to a temperature of about 340°

F. for about 30 minutes.

22. The method of claim 19, wherein

said structural member having two substrates forming said space to be joined are a hem flange joint of an automobile, wherein said two substrates are cleaned, electrodeposition coated, and exposed to a heat source to form said hem flange joint;

said material is then placed in proximity of said space to be joined of said hem flange joint;

said ethylene polymer is about 3.8 percent ethylene-methyl acrylate copolymer;

said epoxy is about 23.49 percent bisphenol A epoxy;

said epoxy resin is comprised of about 24.24 percent bisphenol A epoxy resin and about 0.26 percent epoxy phenol novoiac resin;

said blowing agent is about 0.12 percent azodicarbonamide;

said curing agent is about 1.55 percent cyanoguanidine;

said curing agent accelerator is about 0.5 percent methylene diphenyl bis;

said filler is about 45.84 percent calcium carbonate;

said coloring agent is about 0.19 percent metal oxide; and

said heat source exposes said material to a temperature of about 340°

F. for about 30 minutes.

23. The method of claim 19, wherein said structural member having two substrates forming said space to be joined are a hem flange is pre-crimped.

24. The method of claim 19, wherein said structural member having two substrates forming said space to be joined are a hem flange is crimped.