Composite materials cured with thermoplastic thin film coating

Patent metadata

Field	Value
Publication number	US-10512935-B2
Application number	US-201715583322-A
Country	US
Kind code	B2
Filing date	May 1, 2017
Priority date	May 1, 2017
Publication date	Dec 24, 2019
Grant date	Dec 24, 2019

Abstract

Methods, systems and apparatuses are disclosed for making composite prepreg stacks comprising an outer layer of thermoplastic film that is co-cured with the thermoplastic layer comprising a compressive force on the composite material, along with coated composite materials and larger structures comprising the coated composite materials made according to the disclosed methods.

First claim

What is claimed is:

1. A method for making a coated composite material comprising:
positioning a plurality of prepreg plies to form a shaped composite material prepreg ply stack;
coating a shaped composite material prepreg ply stack with a co-curable continuous coating configured to coat the shaped composite material prepreg ply stack, said co-curable continuous coating comprising a co-curable continuous thermoplastic film, said co-curable continuous thermoplastic film comprising a thermoplastic film first surface and a thermoplastic film second surface, said thermoplastic film first surface located proximate to the shaped composite material prepreg ply stack;
wherein said co-curable continuous thermoplastic film is configured to be an overwrap for the shaped composite material prepreg ply stack, said overwrap configured to completely cover the co-curable shaped composite material prepreg ply stack,
co-curing the shaped composite material prepreg ply stack comprising the thermoplastic film at a temperature ranging from about 250° F. to about 350° F. to form a coated cured composite material; and
wherein the thermoplastic film has a coefficient of thermal expansion that ranges from about 20 to about 70 ppm/° F. at a temperature from about 60° F. to about 350° F.

2. The method of claim 1 , before the step of coating the shaped composite material prepreg ply stack with a thermoplastic film, further comprising;
plasma treating at least the thermoplastic film first surface.

3. The method of claim 1 , wherein, in the step of coating the shaped composite material prepreg ply stack with a thermoplastic film, said thermoplastic film comprises:
a polyether ether ketone or a polyether ketone.

4. The method of claim 1 , wherein, in the step of co-curing the shaped composite material prepreg ply stack and the thermoplastic film, the prepreg ply stack is cured at a temperature ranging from about 250° F. to about 350° F.

5. The method of claim 1 , wherein the plurality of prepreg plies comprise a resin-containing component and a fiber-containing component.

6. The method of claim 1 , wherein, the plurality of prepreg plies comprises an epoxy-containing resin component and a fiber-containing component.

7. The method of claim 6 , wherein, the prepreg plies each comprises a B-stage epoxy-resin.

8. The method of claim 6 , wherein, the prepreg plies comprise an epoxy-resin containing component comprising at least one of:
digylcidyl ethers of bisphenol A; diglycidyl ethers of bisphenol F; N,N,N′,N′-tetragylcidyl-4,4′-diaminophenylmethane; p-amino phenol triglycidyl ether; epoxy phenol novolac resins; epoxy cresol novolac resins; 1,3,5-triglycidyl isocyanurate; tris(2,3-epoxypropyl)isocyanurate; glycerol diglycidyl ether; trimethylolpropane triglycidyl ether, or combinations thereof.

9. The method of claim 1 , wherein the prepreg plies comprise an epoxy-containing resin component and a fiber-containing component, said fiber-containing component comprising at least one of: carbon fibers, glass fibers, boron fibers, aramid fibers, or combinations thereof.

10. The method of claim 1 , wherein the coefficient of thermal expansion of the thermoplastic film is greater than the coefficient of thermal expansion of the shaped composite material prepreg ply stack.

11. A co-curable composite material comprising:
a plurality of co-curable composite material prepreg plies configured into a co-curable shaped composite material prepreg ply stack;
a co-curable continuous coating configured to coat the shaped composite material prepreg ply stack, said co-curable continuous coating comprising a co-curable continuous thermoplastic film, said co-curable thermoplastic film comprising a thermoplastic film first surface and a thermoplastic film second surface, said thermoplastic film first surface located proximate to the shaped composite material prepreg ply stack;

wherein said co-curable continuous thermoplastic film is configured to be an overwrap for the shaped composite material shaped prepreg ply stack, said overwrap configured to completely cover the co-curable shaped composite material prepreg ply stack, said co-curable continuous thermoplastic film having a coefficient of thermal expansion ranging from about 20 to about 70 ppm/° F. at a temperature ranging from about 60° F. to about 350° F.; and
wherein the co-curable thermoplastic film is configured to apply a compressive preload to the shaped composite material prepreg ply stack, said compressive preload ranging from about 0.5 psi to about 10 psi.

12. The co-curable composite material of claim 11 , wherein, the co-curable continuous thermoplastic film comprises:
a polyether ether ketone or a polyether ketone.

13. The co-curable composite material of claim 11 , wherein the coefficient of thermal expansion of the co-curable continuous thermoplastic film is greater than the coefficient of thermal expansion of the co-curable composite material prepreg ply stack.

14. The co-curable composite material of claim 11 , wherein the plurality of co-curable composite material prepreg plies comprise individual prepreg plies, said individual prepreg plies comprising a resin-containing component and a fiber-containing component.

15. The co-curable composite material of claim 14 , wherein the individual prepreg plies comprise an epoxy-containing resin component and a fiber-containing component.

16. The co-curable composite material of claim 14 , wherein the individual prepreg plies comprise an epoxy-containing resin component and a fiber-containing component, said fiber-containing component comprising at least one of: carbon fibers, glass fibers, boron fibers, aramid fibers, or combinations thereof.

17. The co-curable composite material of claim 11 , wherein the co-curable continuous coating has a density ranging from about 1.3 to about 1.4 g/cc.

18. The co-curable composite material of claim 11 , wherein the co-curable continuous coating has a resistivity ranging from about 10 5 to 10 11 ohn/m 2 .

19. The co-curable composite material of claim 11 , wherein the co-curable thermoplastic film is a continuous thermoplastic film configured to provide a barrier to exposed fiber ends present in the co-curable composite material prepreg ply stack.

20. The co-curable composite material of claim 11 , wherein the co-curable thermoplastic film has a Young's modulus value ranging from about 3 GPa to about 20 GPa.

21. The co-curable composite material of claim 11 , wherein the co-curable thermoplastic film comprises a coefficient of thermal expansion that is greater than the coefficient of thermal expansion of the co-curable composite material prepreg ply stack.

Assignees

• Boeing Co

Inventors

• Song Weidong

Classifications

• B29C70/086 Primary

  and with one or more layers of pure plastics material, e.g. foam layers (applying a non-preformed coating, e.g. a gel-coat, B29C37/0025; with foam blocks B29C70/86) · CPC title

• C08J7/0427 Primary

  with only one layer of a composition containing a polymer binder (with more layers C08J7/042) · CPC title

• C08J5/22

  Films, membranes or diaphragms · CPC title

• C08J2373/00

  Characterised by the use of macromolecular compounds obtained by reactions forming a linkage containing oxygen or oxygen and carbon in the main chain, not provided for in groups C08J2359/00 - C08J2371/00; Derivatives of such polymers · CPC title

• C08J2361/16

  of ketones with phenols · CPC title