Oxidation protection coatings for polymers

• US 4,560,577 A
• Filed: 09/11/1984
• Issued: 12/24/1985
• Est. Priority Date: 09/14/1984
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Banks, Bruce A., Sovey, James S., Mirtich, Michael J.
• Primary Examiner(s): Schofer, Joseph L.
• Assistant Examiner(s): SAROFIM, NABIL F
• Application Number:
  US06/649,330
• Time in Patent Office: 469 Days
• Field of Search: 427/38, 427/248.1, 204/298, 204/192 R, 204/192 C, 204/192 D, 428/702, 428/473.5, 428/446
• US Class Current: 427/533
• CPC Class Codes: C23C 14/022 by means of bombardment with energetic particles or radiation
• CPC Class Codes: C23C 14/06 characterised by the coating material C23C14/0021 , C23C14/04 take precedence
• CPC Class Codes: C23C 14/12 Organic material
• CPC Class Codes: Y10T 428/31721 Of polyimide

Abstract

A polymeric substrate 10 is coated with a metal oxide film 22 to provide oxidation protection in low earth orbital environments. The film contains about 4 volume percent polymer to provide flexibility.

A coil of polymer material 30, 42 moves through an ion beam 14 as it is fed between reels. The ion beam first cleans the polymer material surface and then sputters the film material from a target 24 onto this surface.

Claims

1. A method of protecting a polymeric material from oxidation comprising the steps of

mounting said material in a vacuum environment,

exposing said material to a beam of ions in said vacuum environment thereby cleaning absorbed gases and contaminants from a surface of said material, and

mounting a sputter target having a metal oxide portion and a polymer portion in said ion beam for simultaneous co-sputtering thereby sputter coating said cleaned surface in said vacuum environment immediately after cleaning with a continuous thin film comprising a metal oxide and a polymer in a predetermined ratio to form an oxidation barrier.

2. A method of protecting a polymeric material from oxidation as claimed in claim 1 wherein the metal oxide is co-sputtered simultaneously with a polymer.

3. A method of protecting a polymeric material from oxidation as claimed in claim 2 wherein the metal oxide and polymer are co-sputtered to form a thin film having a thickness between about 50 angstroms and about 800 angstroms.

4. A method of protecting a polymeric material from oxidation as claimed in claim 3 wherein the thin film contains a metal oxide selected from the group consisting of SiO₂ and Al₂ O₃.

5. A method of protecting a polymeric material from oxidation as claimed in claim 4 wherein the thin film contains a polymer selected from the group consisting of polytetrafluoroethylene and silicone rubber.

6. A method of protecting a polymeric material as claimed in claim 5 wherein the thin film contains about 96 volume percent SiO₂ and about 4 volume percent polytetrafluoroethylene.