Claims
- 1. An epoxy resin composition which comprises
- a) at least one epoxy resin containing on average more than one 1,2-epoxy group per molecule, which is liquid and of low viscosity,
- b) an anhydride hardener for the epoxy resin a),
- c) a toughener, and
- d) a hydroxycarboxylic acid, a dicarboxylic acid, or a biphenol, which is a mononuclear diphenol, dihydroxy naphthaline, dihydroxy biphenyl or another binuclear aromatic compound which has a methylene, isopropylidene, O, SO.sub.2 or S bridge and contains two hydroxyl groups bound to the aromatic nuclei and wherein the benzene rings may also contain halogen atoms.
- 2. An epoxy resin composition according to claim 1 which additionally contains a filler.
- 3. An epoxy resin composition according to claim 1, wherein the epoxy resin a) is a diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F or a cycloaliphatic diepoxide or is a polyglycidyl ester of a polycarboxylic acid.
- 4. An epoxy resin composition according to claim 1, wherein the epoxy resin a) contains, on average, two 1,2-epoxy groups per molecule.
- 5. An epoxy resin composition according to claim 1, wherein the anhydride hardener b) is a linear aliphatic polymeric anhydride or a cyclic carboxylic acid anhydride.
- 6. An epoxy resin composition according to claim 5, wherein the anhydride hardener b) is a cyclic carboxylic acid anhydride.
- 7. An epoxy resin composition according to claim 1 which additionally contains an accelerator for the anhydride hardener b).
- 8. An epoxy resin composition according to claim 1, wherein the toughener is a core/shell polymer.
- 9. An epoxy resin composition according to claim 8, wherein the shell part of the polymer contains no groups which react with epoxy groups.
- 10. An epoxy resin composition according to claim 1, wherein the amount of the toughener c) is up to 40% by weight, based on the epoxy resin a).
- 11. An epoxy resin composition according to claim 8, wherein the core/shell polymer has a particle size of 0.05-30 .mu.m.
- 12. An epoxy resin composition according to claim 9, wherein the core of the core/shell polymer contains polybutadiene.
- 13. An epoxy resin composition according to claim 1, wherein compound d) contains two phenolic OH groups.
- 14. An epoxy resin composition according to claim 13, wherein compound d) is bisphenol A.
- 15. An epoxy resin composition according to claim 1, wherein the amount of the compound d) is up to 50% by weight, based on the epoxy resin a).
- 16. An epoxy resin composition according to claim 2, wherein the filler is a mineral or fibrous filler.
- 17. An epoxy resin composition according to claim 16, wherein the filler is quartz powder, fused silica, aluminium oxide or dolomite.
- 18. A cured product obtained by curing an epoxy resin composition according to claim 1.
- 19. A process for improving the toughness of epoxy resins, wherein a combination of a toughener with a compound d) according to claim 1 is added to an unfilled or filled epoxy resin/anhydride hardener system.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1055/90 |
Mar 1990 |
CHX |
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Parent Case Info
This is a continuation-in-part of application Ser. No. 674,637, filed Mar. 25, 1991, now abandoned.
US Referenced Citations (6)
Number |
Name |
Date |
Kind |
3856883 |
Dickie et al. |
Dec 1974 |
|
4668736 |
Robins et al. |
May 1987 |
|
4778851 |
Henton et al. |
Oct 1988 |
|
4846905 |
Tarbutton et al. |
Jul 1989 |
|
4894413 |
Catsiff et al. |
Jan 1990 |
|
4983672 |
Almer et al. |
Jan 1991 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
191872 |
Aug 1986 |
EPX |
245018 |
Nov 1987 |
EPX |
Non-Patent Literature Citations (1)
Entry |
Lee and Neville, Handbook of Epoxy Resins, McGraw-Hill Book Co., NY, NY, 1967, pp. 12-1 to 12-37. |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
674637 |
Mar 1991 |
|