Prepreg for use in making composite parts which tolerate hot and wet conditions

Patent metadata

Field	Value
Publication number	US-10472479-B2
Application number	US-201815886008-A
Country	US
Kind code	B2
Filing date	Feb 1, 2018
Priority date	Feb 1, 2018
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

Pre-impregnated composite material (prepreg) that can be cured/molded to form aerospace composite parts that are designed to tolerate hot and wet conditions. The prepreg includes fibers and an uncured resin. The uncured resin includes an epoxy component that is a combination of a trifunctional epoxy resin, a tetrafunctional epoxy resin and a solid epoxy resin. The resin further includes polyethersulfone as a toughening agent and a curing agent.

First claim

What is claimed is:

1. A prepreg that is curable to form a composite material that has an open hole compression of at least 37 at a temperature of 132° C. under wet conditions, said prepreg comprising:
A) fibers; and
B) an uncured resin having a sub glass transition temperature of 0° C. to 5°C., said uncured resin comprising:
a) an epoxy resin component comprising:
1) 22 to 26 weight percent triglycidyl aminophenol epoxy resin, based on the total weight of said uncured resin;
2) 22 to 26 weight percent tetrafunctional epoxy resin, based on the total weight of said uncured resin;
3) 4 to 8 weight percent solid epoxy resin, based on the total weight of said uncured resin wherein said solid epoxy resin is selected from the group of solid epoxy resins having the following formulas:

where G is a glycidyl or epoxide group and n=1.5 to 2; and

b) 15 to 19 weight percent polyethersulfone, based on the total weight of said uncured resin; and
c) a sufficient amount of a curing agent to provide curing of said uncured resin to form said composite material.

2. A prepreg according to claim 1 wherein said tetrafunctional epoxy resin is N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenyl methane.

3. A prepreg according to claim 2 wherein said triglycidyl aminophenol epoxy resin is triglycidyl meta-aminophenol epoxy resin.

4. A prepreg according to claim 1 wherein said triglycidyl aminophenol epoxy resin is triglycidyl meta-aminophenol epoxy resin.

5. A prepreg according to claim 1 wherein the weight ratio of said triglycidyl aminophenol epoxy resin to said tetrafunctional epoxy resin is 1:1.

6. A prepreg according to claim 1 wherein said curing agent is an aromatic amine.

7. A prepreg according to claim 6 wherein said aromatic amine is 3,3′-diaminodiphenyl sulphone.

8. A composite part or structure that has been formed by curing a prepreg according to claim 1 .

9. A composite part or structure according to claim 8 wherein said composite part or structure forms at least part of an aircraft engine nacelle.

10. A method for making a composite part or structure comprising the steps of providing a prepreg according to claim 1 and curing said prepreg to form said composite part or structure.

11. A method for making a prepreg that is curable form a composite material that has an open hole compression of at least 37 at a temperature of 132° C. under wet conditions, said method comprising the steps of:
A) providing fibers; and
B) impregnating said fibers with an uncured resin having a sub glass transition temperature of 0° C. to 5°C., said uncured resin comprising:
a) an epoxy resin component comprising:
1) 22 to 26 weight percent triglycidyl aminophenol epoxy resin, based on the total weight of said uncured resin;
2) 22 to 26 weight percent tetrafunctional epoxy resin, based on the total weight of said uncured resin;
3) 4 to 8 weight percent solid epoxy resin, based on the total weight of said uncured resin wherein said solid epoxy resin is selected from the group of solid epoxy resins having the following formulas:

where G is a glycidyl or epoxide group and n=1.5to 2; and

b) 15 to 19 weight percent polyethersulfone, based on the total weight of said uncured resin; and
c) a sufficient amount of a curing agent to provide curing of said uncured resin to form said composite material.

12. A method for making a prepreg according to claim 11 wherein said tetrafunctional epoxy resin is N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenyl methane.

13. A method for making a prepreg according to claim 11 wherein said triglycidyl aminophenol epoxy resin is triglycidyl meta-aminophenol epoxy resin.

14. A method for making a prepreg according to claim 11 wherein said curing agent is an aromatic amine.

15. A method for making a prepreg according to claim 14 wherein said aromatic amine is 3,3′-diaminodiphenyl sulphone.

Assignees

• Hexcel Corp

Inventors

• Wang Yen-Seine
• Emmerson Gordon

Classifications

• C08J2463/00

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

• C08J5/042 Primary

  with carbon fibres · CPC title

• C08J2363/00

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

• C08J2481/06

  Polysulfones; Polyethersulfones · CPC title

• B64D29/00

  Power-plant nacelles, fairings or cowlings · CPC title