Prepreg and fiber-reinforced rubber materials

• US 6,453,960 B1
• Filed: 10/20/2000
• Issued: 09/24/2002
• Est. Priority Date: 02/22/1999
• Status: Expired due to Fees

• Current Assignee: Toray Industries Incorporated
• Original Assignee: Toray Industries Incorporated
• Inventors: Kondo, Haruhiko, Manabe, Takao, Kishi, Hajime
• Primary Examiner(s): Dawson, Robert
• Assistant Examiner(s): Feely, Michael J
• Application Number:
  US09/673,730
• Time in Patent Office: 704 Days
• Field of Search: 428/413, 428/297.4, 428/299.1, 428/521, 428/522, 152/451, 152/527, 152/556
• US Class Current: 152/451
• CPC Class Codes: C08J 2321/00 Characterised by the use of unspecified rubbers
• CPC Class Codes: C08J 5/243 using carbon fibres
• CPC Class Codes: C08J 5/249 characterised by the additives used in the prepolymer mixture
• CPC Class Codes: F16G 1/08 with reinforcement bonded by the rubber
• CPC Class Codes: F16G 5/06 with reinforcement bonded by the rubber
• CPC Class Codes: Y10T 428/24994 Fiber embedded in or on the surface of a polymeric matrix
• CPC Class Codes: Y10T 428/249945 Carbon or carbonaceous fiber
• CPC Class Codes: Y10T 428/31511 Of epoxy ether
• CPC Class Codes: Y10T 428/31931 Polyene monomer-containing
• CPC Class Codes: Y10T 428/31935 Ester, halide or nitrile of addition polymer

Abstract

The object is to provide a carbon fiber-reinforced rubber material which is superior in heat resistance, water resistance, and dimensional stability and exhibits resistance to fatigue from flexing at a practical level. The present invention relates to a prepreg comprising a liquid rubber composition having a viscosity in a range of 0.01 Pa·s to 100 Pa·s at 70° C. and substantially containing no solvent, the liquid rubber being impregnated into a reinforcing fiber, and relates to a fiber-reinforced rubber material comprising the prepreg in which the liquid rubber is crosslinked. Also, the present invention relates to a fiber-reinforced rubber material comprising a substrate comprising a rubber component, the substrate being reinforced by a core material comprising a prepreg of a reinforcing fiber impregnated with the same rubber component.

Claims

1. A prepreg comprising a reinforcing fiber and a liquid rubber composition, wherein the liquid rubber composition has a viscosity in a range of 0.01 Pa·

s to 100 Pa·

s at 70°

C. and contains substantially no solvent, and comprises an epoxy resin having an epoxy equivalent of 250 to 2,500.

2. A prepreg according to claim 1, wherein the epoxy resin has a flexible skeleton.

3. A prepreg according to claim 1, wherein the epoxy resin is at least one selected from the group consisting of polyethylene glycol diglycidyl ether, polypropylene diglycidyl ether, and a diglycidyl ester of dimer acid.

4. A prepreg of claim 1, wherein the liquid rubber composition contains 1 percent or less by weight of solvent based on the overall weight of the liquid rubber composition.

5. A prepreg according to claim 1, wherein the liquid rubber composition comprises a liquid polymer having a number average molecular weight of 500 to 5,000.

6. A prepreg according to claim 1 or 5, wherein the liquid rubber composition comprises telechelic polymer.

7. A prepreg according to claim 1 or 5, wherein the liquid rubber composition comprises at least one liquid polymer selected from the group consisting of liquid acrylonitrile-butadiene copolymer, liquid polyisoprene, and liquid polybutadiene.

8. A fiber-reinforced rubber material obtained by crosslinking the liquid rubber composition in a prepreg according to claim 1 or 5.

9. A tire comprising a fiber-reinforced rubber material according to claim 8.

10. A belt comprising a fiber-reinforced rubber material claim 8.

18. A prepreg according to claim 1 or 11, wherein the reinforcing fiber has a tensile strength of 4,000 MPa or more.

19. A prepreg according to either claim 1 or 11, wherein the reinforcing fiber has a breaking elongation of 1.6% or more.

11. A prepreg comprising a reinforcing fiber and a liquid rubber composition, the liquid rubber composition having a viscosity in a range of 0.01 Pa·

s to 100 Pa·

s at 70°

C. and containing substantially no solvent, wherein the reinforcing fiber is carbon fiber.

12. A prepreg according to claim 11, wherein the liquid rubber composition comprises a liquid polymer having a number average molecular weight of 500 to 5,000.

13. A prepreg according to claim 11, wherein the liquid rubber composition comprises a telechelic polymer.

14. A prepreg according to claim 11, wherein the liquid rubber composition comprises at least one liquid polymer selected from the group consisting of liquid acrylonitrile-butadiene copolymer, liquid polyisoprene, and liquid polybutadiene.

15. A prepreg according to claim 11, wherein the liquid rubber composition comprises an epoxy resin and the epoxy equivalent of the epoxy resin is in a range of 250 to 2,500.

16. A prepreg according to claim 15, wherein the epoxy resin has a flexible skeleton.

17. A prepreg according to claim 16, wherein the epoxy resin is at least one selected from the group consisting of polyethylene glycol diglycidyl ether, polypropylene diglycidyl ether, and a diglycidyl ester of dimer acid.

20. A fiber-reinforced rubber material comprising a substrate and a core material;

wherein said substrate comprises at least one rubber component;

wherein said core material comprises a prepreg comprising a reinforcing fiber and at least one rubber component;

wherein said substrate and said core material comprise a common rubber component of the same kind of rubber;

wherein 50 to 100 wt % of rubber components in the substrate comprise said common rubber component; and

wherein 50 to 100 wt % of rubber components in the core material comprise said common rubber component.

21. A fiber-reinforced rubber material according to claim 20, wherein the common rubber component comprises an acrylonitrile-butadiene rubber having a bonded nitrile content in the range is selected from the group consisting of 24% or less, 25 to 30%, 31 to 35%, 36 to 42% or more.

22. A fiber-reinforced rubber material according to claim 20, wherein the common rubber component of the same kind comprises acrylonitrile-butadiene rubber.

23. A fiber-reinforced rubber material according to claim 22, wherein the acrylonitrile-butadiene rubber in the substrate is the same type of acrylonitrile-butadiene rubber as that in the core.

24. A fiber-reinforced rubber material according to any one of claims 20 to 23, wherein the common rubber component of the substrate and the common rubber component of the core material comprise a monomer residue rate, wherein the monomer residue rate in the substrate differs from the monomer residue rate in the core by 10 weight percent or less.

25. A fiber-reinforced rubber material according to any one of claims 20 to 23, wherein the common rubber component of the substrate and the common rubber component of the core material comprise a copolymer having a component ratio, wherein the component ratio in the substrate differs from the component ratio in the core by 10 weight percent or less.

26. A fiber-reinforced rubber comprising the fiber-reinforced rubber material according to any one of claims 20 to 23, wherein the reinforcing fiber is carbon fiber.

27. A fiber-reinforced rubber according to claim 26, wherein the carbon fiber has a tensile strength of 4,000 MPa or more.

28. A fiber-reinforced rubber according to claim 26, wherein the carbon fiber has a breaking elongation of 1.6% or more.

29. A tire comprising a fiber-reinforced rubber material according to any one of claims 20 and 22.

30. A belt comprising a fiber-reinforcing rubber material according to any one of claims 20 to 22.

31. A fiber-reinforced rubber material comprising a substrate and a core material;

wherein said substrate comprises at least one rubber component;

wherein said core material comprises a prepreg comprising a reinforcing fiber and at least one rubber component;

wherein said substrate and said core material comprise a common rubber component of the same kind of rubber having structural repeating units;

wherein the common rubber component in the substrate comprises a structural repeating unit having the same chemical formula as the structural repeating unit in the common rubber component of the core material;

wherein 50 to 100 wt % of rubber components in the substrate comprise said common rubber component; and

wherein 50 to 100 wt % of rubber components in the core material comprise said common rubber component.