Accession Number:

ADA383716

Title:

Fundamental Models for Predicting Lifetime Performance of High Performance Polymeric Materials

Descriptive Note:

Final rept. 1 Mar 1995-31 Aug 1998

Corporate Author:

PURDUE UNIV LAFAYETTE IN

Personal Author(s):

Report Date:

1998-08-01

Pagination or Media Count:

40.0

Abstract:

1H, 2H, 3C and 15N solid state NMR techniques were used to investigate high performance polyimide resins. Solid state 15N NMR appears to be the most sensitive technique to the chemical reactions involved in the cure and degradation of polyimide resins. The AFR700 cure reaction pathways are very similar to amine cured bismaleimide chemistry and appears to be much more complex than PMR type systems. The AFR backbone is relatively robust under hydrolytic conditions. The AFR700 end-groups in the cured polymer are not stable under these conditions. A large volume MAS probe has been built for operation at 9.4 Tesla. The probe will spin a 10 nm zirconia rotar at 4 kHz. The mechanical design is easily scaled to even larger systems. This 10 nm probe requires only one-fourth the time to acquire the same signal-to-noise ratio as a commercial 5 mm probe.

Subject Categories:

  • Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE