Motion of midchain peroxy radicals in poly(tetrafluoroethylene)
Electron spin resonance (ESR) spectra at X band for the midchain peroxy radical (-CF/sub 2/CF(OO.)-CF/sub 2/-) in ..gamma..-irradiated poly(tetrafluoroethylene) (PTFE) are studied in the temperature range 300-500 K. The midchain fluoroalkyl radical (-CF/sub 2/CFCF/sub 2/-) is formed by decomposition of peroxy radicals and splittings from ..cap alpha..-, ..beta.., and ..gamma..-fluorine nuclei are respectively 88.0, 31.5, and 3.0 G at 493 K. Line widths from the midchain peroxy radicals increase with increasing temperature and are analyzed in terms of a motional process with an activation energy of 16.1 kJ/mol. The suggested motional model is a helical twisting of the polymer axis as has been observed in the end-chain peroxy radical in poly(tetrafluoroethylene) and in poly(vinylidene fluoride).
- Research Organization:
- Univ. of Windsor, Ontario, Canada
- OSTI ID:
- 5999283
- Journal Information:
- J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 87:2; ISSN JPCHA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
400600* -- Radiation Chemistry
CHEMICAL RADIATION EFFECTS
CHEMISTRY
ELECTROMAGNETIC RADIATION
ELECTRON SPIN RESONANCE
FLUORINATED ALIPHATIC HYDROCARBONS
GAMMA RADIATION
HALOGENATED ALIPHATIC HYDROCARBONS
IONIZING RADIATIONS
MAGNETIC RESONANCE
MOTION
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
PEROXY RADICALS
POLYETHYLENES
POLYMERS
POLYOLEFINS
POLYTETRAFLUOROETHYLENE
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADICALS
RESONANCE
SPECTRA