Friction Transition In Polyimide Films as Related to Molecular Relaxations and Structure.
Abstract
The friction characteristics of polyimide films bonded to metallic substrates were studied from 25 C to 500 C. These results were correlated to molecular structure and the results of torsional braid analysis (TBA). A large friction transition (0. 23 to 0.03) was found to occur at 45 C + OR - 5 C. It was postulated that this transition was initiated by some molecular relaxation, which gave the molecules a degree of freedom by which an external mechanical stress could rearrange the molecules into a structure, such as an extended chain, which is conducive to easy shear. Above 300 C the friction characteristics were found to be dependent on the thermal prehistory of the film. (MM)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1975
- Accession Number
- ADA303579
Entities
People
- Robert L. Fusaro
Organizations
- Glenn Research Center