Methods involving oxygen plasma exposure to improve adhesion of silicate thermal coatings

Patent metadata

Field	Value
Publication number	US-11261335-B1
Application number	US-201816140878-A
Country	US
Kind code	B1
Filing date	Sep 25, 2018
Priority date	Sep 25, 2018
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A method of making a thermal control coating is provided. A primer layer can be applied to a substrate to form an exposed surface. The primer layer can include an epoxy binder and a silica filler. The exposed surface can be treated with an oxygen plasma to form a treated surface. A silicate-based thermal control coating can be applied to the treated surface, for example, by spraying, to form a thermal control coating on the substrate. Spacecraft and spacecraft hardware components coated with the thermal control coating, are also provided.

First claim

What is claimed is:

1. A method of making a thermal control coating, comprising steps of:
applying a primer layer to a substrate, the primer layer comprising an epoxy binder and a silica filler, the primer layer having an exposed surface;
treating the exposed surface with an oxygen plasma by treating said exposed surface with a glow discharge oxygen plasma in a glow discharge chamber for at least two hours to oxidize the epoxy binder at the exposed surface to thereby increase a surface area of said silica filler at the exposed surface to at least 50% thereof to form a treated surface; and
spraying a silicate-based thermal control coating material on the treated surface under conditions such that the silicate-based thermal control coating material chemically bonds to the treated surface and said thermal control coating is formed; and
wherein said step of treating the exposed surface with said oxygen plasma improves an adhesive bond strength between the primer layer and the silicate-based thermal control coating and does not impact the primer layer maintaining a bond to said substrate and thereby creating a spacecraft hardware thermal control coating.

2. The method of claim 1 , wherein the substrate comprises a polyimide tape.

3. The method of claim 1 , wherein the substrate is a flexible tape.

4. A method of making a thermal control coating, comprising steps of:
Applying a primer layer to a substrate, the primer layer comprising an epoxy binder and a silica filter, the primer layer having an exposed surface;
treating the exposed surface with an oxygen plasma by treating said exposed surface with a glow discharge oxygen plasma in a glow discharge chamber for at least two hours to oxidize the epoxy binder at the exposed surface to thereby increase a surface area of said silica filler at the exposed surface to at least 50% thereof to form a treated surface; and
spraying a silicate-based thermal control coating material on the treated surface under conditions such that the silicate-based thermal control coating material chemically bonds to the treated surface and said thermal control coating formed; and
wherein said step of treating the exposed surface with said oxygen plasma improves an adhesive bond strength between the primer layer and the silicate-based thermal control coating and does not impact the primer layer maintaining a bond to said substrate and thereby creating a spacecraft hardware thermal control coating; and
wherein the apply the silicate-based thermal control coating material comprises first mixing electrically conductive component with said silicate-based thermal control coating material to form a conductive coating material that is then applied as the silicate-based thermal control coating material; and
wherein the method of making said thermal control coating first comprises a step of mixing more of the same electrically conductive component that is mixed with the silicate-based thermal control coating material with said epoxy binder and a silica filler before said step of applying said primer layer to said substrate.

5. The method of claim 1 , wherein the primer layer is electrically insulative and non-conductive.

6. The method of claim 1 , wherein the silicate-based thermal control coating material is applied to a thickness of from about 0.1 mil to about 20 mils.

7. The method of claim 1 , wherein the silicate-based thermal control coating material is applied to a thickness of from about 0.5 mil to about 1.5 mils.

8. The method claim 1 , wherein the primer layer is applied to a thickness of from about 3.0 to about 5.0 mils.

Assignees

• Nasa

Inventors

• Hasegawa Mark M
• O'Connor Kenneth
• Miller Grace M
• Wong Alfred
• Harris George M

Classifications

• B64G1/58

  Thermal protection, e.g. heat shields · CPC title

• C08J7/123

  Treatment by wave energy or particle radiation (C08J7/18 takes precedence) · CPC title

• C09D5/002

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

• C09D1/00 Primary

  Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances · CPC title

• C08K3/36

  Silica · CPC title