Water soluble barrier coatings for washout tooling for a composite layup

Patent metadata

Field	Value
Publication number	US-11524427-B2
Application number	US-202017126457-A
Country	US
Kind code	B2
Filing date	Dec 18, 2020
Priority date	Dec 18, 2020
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A washout tooling for a composite layup is provided. The washout tooling comprises a casting mold having an exterior surface. The casting mold comprises a particulate material and a water-soluble binder. The casting mold is adapted to break down in the presence of an aqueous solution. The washout tooling further comprises a water-soluble coating layer overlying the exterior surface. The water-soluble coating layer is adapted to break down in the presence of an aqueous solution. The washout tooling further comprises a curable composite layer overlying the water-soluble coating layer. The water-soluble coating layer minimizes contact between the particulate material and the curable composite layer.

First claim

The invention claimed is:

1. A washout tooling for a composite layup, comprising:
a mold having an exterior surface, the mold comprising a particulate material and a water-soluble binder, the mold adapted to break down in the presence of an aqueous solution;
a water-soluble coating layer overlying the exterior surface of the mold, the water-soluble coating layer being adapted to break down in the presence of an aqueous solution; and
a curable composite layer overlying the water-soluble coating layer opposite of the mold, the curable composite layer including a plurality of fibers and a curable resin;
wherein the water-soluble coating layer minimizes contact between the particulate material and the curable resin of the curable composite layer,
wherein the water-soluble coating layer comprises a water-soluble coating material having a glass transition temperature of from about 50° C. to about 500° C. according to ASTM D7028-07(2015), and
wherein the water-soluble coating material comprises a neutralizing component, the neutralizing component comprising sodium hydroxide, potassium hydroxide, poly(vinyl pyrrolidone), or combinations thereof.

2. The washout tooling of claim 1 , wherein the water-soluble coating layer has a water solubility of from about 10 g to about 70 g in 100 g water at 23° C. according to OECD 105.

3. The washout tooling of claim 1 , wherein the water-soluble coating material comprises a water-soluble polymer, the water-soluble polymer comprising poly(vinyl alcohol), poly(acrylic acid), poly(acrylic acid, sodium salt), poly(sodium 4-styrenesulfonate), poly(vinylsulfonic acid, sodium salt), or combinations thereof.

4. The washout tooling of claim 1 , wherein the water-soluble coating material comprises a solvent, the solvent comprising methanol, 1-propanol, ethanol, isopropanol, water, or combinations thereof.

5. A washout tooling for a composite layup, comprising:
a mold having an exterior surface, the mold comprising a particulate material and a water-soluble binder, the mold adapted to break down in the presence of an aqueous solution;
a water-soluble coating layer overlying the exterior surface of the mold, the water-soluble coating layer being adapted to break down in the presence of an aqueous solution; and
a curable composite layer overlying the water-soluble coating layer opposite of the mold, the curable composite layer including a plurality of fibers and a curable resin;
wherein the water-soluble coating layer minimizes contact between the particulate material and the curable resin of the curable composite layer,
wherein the water-soluble coating layer comprises a water-soluble coating material having a glass transition temperature of from about 50° C. to about 500° C. according to ASTM D7028-07(2015), and
wherein the water-soluble coating material comprises a filler, the filler comprising a nanofiller, salts, or combinations thereof.

6. The washout tooling of claim 1 , wherein the aqueous solution includes an alcohol, ketones, acetates, cyclic ethers, or combinations thereof.

7. The washout tooling of claim 1 , wherein the particulate material comprises a sand, a gypsum, a metal, or a ceramic powder.

8. The washout tooling of claim 1 , wherein the water-soluble binder comprises a poly(ethyleneimine), poly(vinyl pyrrolidone), poly(vinyl alcohol), poly(acrylic acid), poly(vinylsulfonic acid, sodium salt), copolymers thereof, or combinations thereof.

9. The washout tooling of claim 1 , wherein the plurality of fibers comprise carbon fibers.

10. The washout tooling of claim 1 , wherein break down of the mold is in the presence of the aqueous solution at a temperature of from about 23° C. to about 100° C. and at a pressure of at least 40 psi.

11. The washout tooling of claim 1 , wherein break down of the water-soluble coating layer is in the presence of the aqueous solution at a temperature of from about 23° C. to about 100° C. and at a pressure of at least 40 psi.

12. A method for forming a composite layup, the method comprising:
combining a particulate material and a water-soluble binder to form a mold having an exterior surface;
applying a water-soluble coating material to the exterior surface of the mold to form a water-soluble coating layer;
applying a curable composite material to the water-soluble coating layer opposite of the mold to form a curable composite layer, the curable composite layer including a plurality of fibers and a curable resin;
curing the curable resin to form a hardened composite layup; and
exposing the mold and the water-soluble coating layer to an aqueous solution to wash the hardened composite layup free of the mold and the water-soluble coating;
wherein the water-soluble coating layer minimizes contact between the particulate material and the curable resin of the curable composite layer
wherein applying the water-soluble coating material comprises submerging the mold in the aqueous solution, and
wherein the water-soluble coating material comprises poly(acrylic acid).

13. The method of claim 12 , wherein submerging the casting mold in the water-soluble coating material comprises:
submerging the mold in the water-soluble coating material;
removing the mold from the water-soluble coating material; and
submerging the mold in the water-soluble coating material.

14. A method for forming a composite layup, the method comprising:
combining a particulate material and a water-soluble binder to form a mold having an exterior surface;
applying a water-soluble coating material to the exterior surface of the mold to form a water-soluble coating layer;
applying a curable composite material to the water-soluble coating layer opposite of the mold to form a curable composite layer, the curable composite layer including a plurality of fibers and a curable resin;
curing the curable resin to form a hardened composite layup; and
exposing the mold and the water-soluble coating layer to an aqueous solution to wash the hardened composite layup free of the mold and the water-soluble coating;
wherein the water-soluble coating layer minimizes contact between the particulate material and the curable resin of the curable composite layer,
wherein applying the water-soluble coating material comprises spraying the mold with the water-soluble coating material, and
wherein the water-soluble coating material comprises poly(vinylsulfonic acid, sodium salt).

15. The method of claim 12 , wherein combining the particulate material and the water-soluble binder comprises jetting the water-soluble binder on the particulate material to form the mold.

16. A washout tooling for a composite layup, comprising:
a casting mold having an exterior surface, the casting mold comprising a particulate material and a water-soluble binder, the casting mold adapted to break down in the presence of an aqueous solution;
a water-soluble coating layer overlying the exterior surface, the water-soluble coating layer adapted to break down in the presence of an aqueous solution; and
a curable composite layer overlying the water-soluble coating layer;
wherein the water-soluble coating layer minimizes contact between the particulate material and the curable composite layer, and
wherein the water-soluble coating layer comprises a neutralizing component, the neutralizing component comprising sodium hydroxide, potassium hydroxide, poly(vinyl pyrrolidone), or combinations thereof.

17. A washout tooling for a composite layup, comprising:
a casting mold having an exterior surface, the casting mold comprising a particulate material and a water-soluble binde

Assignees

• Ut Battelle Llc
• Univ Tennessee Res Found

Inventors

• Saito Tomonori
• Han Lu
• Elliott Amelia M
• Gilmer Dustin B

Classifications

• C09D5/002

  Priming paints (C09D5/08 takes precedence) · CPC title

• C09D7/61

  inorganic · CPC title

• B29C70/54

  Component parts, details or accessories; Auxiliary operations {, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing} · CPC title

• C09D133/02

  Homopolymers or copolymers of acids; Metal or ammonium salts thereof · CPC title

• C08K3/346

  Clay · CPC title