Polyimide developed by the interaction of benzophenone tetracarboxylic dianhydride, polyoxypropylene diamine, and oxydianiline is used for fuel tanks that are exposed to extreme temperatures

Clark, B. F.

Roscoe, J. S.

English

NASA Technical Reports Server

July 1972 
•	
NASA TECH BRIEF 
Marshall Space Flight Center 
B72-10262 
NASA Tech Briefs announce new technology derived from the U.S. space program. They are issued to encourage 
commercial application. Tech Briefs are available on a subscription basis from the National Technical Information 
Service, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech Brief program may 
be directed to the Technology Utilization Office, NASA, Code KT, Washington, D.C. 20546. 
Development of a Polyimide for Use as a Tern 
and Solvent Resistant Sealant 
The problem:	 Adhesion (Lap shear) 
A special polymer sealant is needed for fuel tanks 	 Tensile Strength 
that are used at extreme temperatures. Such a polymer	 Elongation 
should be solvent and temperature resistant and corn- 	 Compression set 
patible with titanium alloys.
perature 
2.42 x 106 N/rn 2 (350 psi) 
1.24 x 10 N/rn 2 (1800 psi) 
400 to 600% 
85% 
The solution: 
A polyimide was developed by the interaction of 
benzophenone tetracarboxylic dianhydride (BDTA), 
polyoxypropylene diamine (POPDA), and oxydianiline 
(ODA). Its properties are more suitable than anything 
previously available. 
How it's done: 
An aromatic dianhydrid and a diamine react to give a 
polyarnide-acid intermediate readily converted to a 
polyimide by heating. Currently, the polyimides with the 
best high-temperature sealant properties are made from 
BTDA and POPDA with smaller amounts of ODA, 
methylenedianiline (MDA), and a curing agent such as 
EM-308. The following is a table of properties achieved: 
Property	 Test Result 
Thermal stability	 233K to 533K (-40F to 
450°F) 
Solvent resistance	 H20 resistant, 5% volume 
swell after 24 days at 
300K (75°F)
These polymers might also be useful as sealant coat-
ings for metals other than titanium when high-tempera-
ture and solvent reliability is desired. 
Note: 
Requests for further information may be directed to: 
Technology Utilization Officer 
Marshall Space Flight Center 
Code A & TS-TU 
Huntsville, Alabama 35812 
Reference: B72-10262 
Patent status: 
No patent action is contemplated by NASA. 
Source: J. S. Roscoe and B. F. Clark of 
Quantum, Inc. 
under contract to
Marshall Space Flight Center 
(MFS-21 325) 
Category 04 
This document was prepared under the sponsorship of the National 	 Government assumes any liability resulting from the use of the 
Aeronautics and Space Administration. Neither the United States 	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States 	 will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19720000262 2020-03-17T03:27:34+00:00Z


Development of a polyimide for use as a temperature and solvent resistant sealant

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server