Abstract

PMR-15 polyimide is a high performance polymer that is widely used in high temperature applications of composites. The presence of free radicals at room temperature in this polyimide has been confirmed recently by electron paramagnetic resonance (EPR, or ESR) spectroscopy of PMR-15 resin samples. These free radicals are generated when the resin samples are exposed to temperatures above 300xC and are found to be relatively stable at room temperatures. The weight loss data at an elevated temperature suggest that the free radicals are directly involved in the oxidative degradation of the polyimide in the presence of oxygen. The goal of this project is to measure the static magnetic susceptibility of a PMR-15 resin sample using a superconducting quantum interference device (SQUID) magnetometer and compared the susceptibility data with EPR results reported earlier.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
2P41RR001811-11
Application #
5223721
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
11
Fiscal Year
1996
Total Cost
Indirect Cost

  Publications

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Maringanti, S; Imlay, J A (1999) An intracellular iron chelator pleiotropically suppresses enzymatic and growth defects of superoxide dismutase-deficient Escherichia coli. J Bacteriol 181:3792-802

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