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Updated: Dec 25, 2025
06:55
Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
8.3K
Gamma Irradiation of Fluorocarbon Polymers.
Summary
Gamma radiation significantly alters fluorocarbon polymers. Polytetrafluoroethylene and its copolymer degrade faster in air due to radiation-induced chain scission, involving free-radical mechanisms.
Area of Science:
- Polymer Science
- Radiation Chemistry
- Materials Science
Background:
- Fluorocarbon polymers exhibit unique properties.
- Understanding their response to radiation is crucial for applications.
Purpose of the Study:
- To investigate the effects of gamma radiation on various fluorocarbon polymers.
- To determine the mechanisms of radiation-induced degradation and crosslinking.
Main Methods:
- Irradiation of fluorocarbon polymers with Co60 gamma radiation.
- Measurement of G-values for volatile products and free radicals (ESR).
- Assessment of polymer integrity using zero-strength-time and tensile-strength tests.
Main Results:
- Polytetrafluoroethylene and its hexafluoropropylene copolymer showed accelerated scission in the presence of air.
- Free radicals were detected, indicating a free-radical mediated process.
- Degradation and crosslinking varied among the studied polymers.
Conclusions:
- Gamma radiation induces significant changes in fluorocarbon polymers.
- Air presence dramatically enhances radiation-induced scission in specific polymers.
- Free-radical intermediates play a key role in the observed radiation effects.
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