Peroxy radical probe for motion in poly(tetrafluoroethylene) chains. [Gamma radiation]

Journal Article · Tue Feb 09 23:00:00 EST 1982 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00367a006· OSTI ID:5113811

Suryanarayana, D ^[1]; Kevan, L; Schlick, S

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1. Univ. of Houston, TX

The temperature dependences in the Q-band electron-spin resonance (ESR) spectra of mid-chain and end-chain peroxy radicals in ..gamma..-irradiated poly(tetrafluoroethylene) are investigated experimentally and theoretically, using modified Bloch equations. Computer simulations are carried out for the following motional models: cubic jump, C-O bond rotation (120/sup 0/ and 180/sup 0/ jumps), and chain axis rotation (90/sup 0/ and 120/sup 0/ jumps). For the mid-chain peroxy radical (-CF/sub 2/CF(00)-CF/sub 2/), the partial g averaging in the ESR spectra could be fit well by chain axis rotation with 90/sup 0/ jumps, whereas the complete g averaging observed at room temperature for the end-chain peroxy radical (-CF/sub 2/-CF/sub 2/-CF/sub 2/(00)) could be fit using a cubic jump model. An activation energy of 18.4 kJ/mol was found for the mid-chain peroxy-radical motion and 11.2 kJ/mol for the end-chain peroxy-radical motion. 11 figures.

• OSTI ID: 5113811
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 104:3; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
ABSORPTION SPECTRA
ACTIVATION ENERGY
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
COMPUTERIZED SIMULATION
DATA
DECOMPOSITION
ELECTROMAGNETIC RADIATION
ELECTRON SPIN RESONANCE
ENERGY
EXPERIMENTAL DATA
FLUORINATED ALIPHATIC HYDROCARBONS
GAMMA RADIATION
HALOGENATED ALIPHATIC HYDROCARBONS
HIGH TEMPERATURE
INFORMATION
IONIZING RADIATIONS
MAGNETIC RESONANCE
MATHEMATICS
MOTION
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
PEROXY RADICALS
POLYETHYLENES
POLYMERS
POLYOLEFINS
POLYTETRAFLUOROETHYLENE
POWDERS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOLYSIS
RESONANCE
ROTATION
SIMULATION
SPECTRA
STRUCTURAL CHEMICAL ANALYSIS
TEMPERATURE DEPENDENCE
THEORETICAL DATA