Curing composite materials comprising latent-cure resins

Patent metadata

Field	Value
Publication number	US-9469055-B2
Application number	US-201214360199-A
Country	US
Kind code	B2
Filing date	Nov 14, 2012
Priority date	Nov 23, 2011
Publication date	Oct 18, 2016
Grant date	Oct 18, 2016

Abstract

The invention relates to a method for curing of a composite material. The method involves applying heat to only a first region of said composite material, such that said first region is heated to a temperature above the cure onset temperature of said curable resin, thus initiating curing of said curable resin in said first region; and maintaining the composite material in an insulated state, such that the curing of said curable resin spreads to regions of the composite material outside of said first region.

First claim

The invention claimed is:

1. A method for curing of a composite material, said method comprising:
a. providing a composite material comprising at least one layer of fibrous material and curable resin;
b. applying heat to at least one first region of said composite material, such that said first region is heated to a temperature above the cure onset temperature of said curable resin, thus curing said curable resin in said first region;
c. maintaining the composite material in an insulated state, such that the heat from the exothermic curing reaction in said first region acts to heat at least one uncured second region of the composite material to a temperature above the cure onset temperature of said curable resin in said at least one second region, such that the curing of said curable resin spreads from cured to uncured regions of the composite material at a temperature above the cure onset temperature.

2. The method according to claim 1 , wherein the composite material is a composite laminate comprising at least two layers of fibrous material.

3. The method according to claim 1 , wherein the composite material is maintained in adiabatic conditions during step (c).

4. The method according to claim 1 , wherein the curing of the curable resin spreads from said first region across the entirety of the composite material.

5. The method according to claim 1 , wherein the composite material is pre-heated to a temperature above ambient temperature, yet below the cure onset temperature of the curable resin, before step b.

6. The method according to claim 1 , wherein—after onset of curing at least in said first region—the heat is removed from said first region.

7. The method according to claim 1 , wherein at least one layer of the fibrous material is at least partially pre-impregnated with said curable resin.

8. The method according to claim 1 , wherein the fibrous material is selected from the group consisting of glass fibres, carbon fibres, aramid fibres, polyethylene fibres, natural fibres or combinations thereof; preferably carbon fibres.

9. The method according to claim 1 , wherein the curable resin is selected from the group consisting of epoxy, polyester, vinyl ester, polyimide, cyanate ester, phenolic and bismaleimide resins and blends thereof; preferably epoxy resin.

10. The method according to claim 1 , wherein the curable resin is an adhesive resin or a matrix resin.

11. The method according to claim 1 , wherein the composite material has a thickness of at least 10 mm.

12. The method according to claim 1 , wherein at least steps b. and c. are carried out in a vacuum.

13. A method for the manufacture of a formed article, said method comprising steps a. b. and c. according to claim 1 , said method further comprising the step of moulding the composite material according to the desired form of said formed article.

14. The method according to claim 1 , where the method is used in manufacturing of a wind turbine blade.

15. The method according to claim 1 , wherein the composite material has a thickness of at least 25 mm.

16. The method according to claim 1 , wherein the composite material has a thickness of at least 50 mm.

Assignees

• Vestas Wind Sys As

Inventors

• Bech Anton

Classifications

• C08J2363/00

  Characterised by the use of epoxy resins; Derivatives of epoxy resins · CPC title

• C08J3/247

  Heating methods · CPC title

• B29K2101/10

  Thermosetting resins · CPC title

• C08J2367/06

  Unsaturated polyesters · CPC title

• C08J3/244

  Stepwise homogeneous crosslinking of one polymer with one crosslinking system, e.g. partial curing · CPC title