ESR study on free radicals trapped in crosslinked polytetrafluoroethylene (PTFE)

被引：75

作者：

Oshima, A

Seguchi, T

Tabata, Y

机构：

[1] Tokai Univ, Dept Nucl Engn, Kanagawa 25912, Japan

[2] Takasaki Radiat Chem Res Estab, Japan Atom Energy Res Inst, Gunma 37012, Japan

来源：

RADIATION PHYSICS AND CHEMISTRY | 1997年 / 50卷 / 06期

关键词：

D O I：

10.1016/S0969-806X(97)00079-0

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Free radicals in crosslinked PTFE which formed by Co-60 gamma-rays irradiation at 77 K and at room temperature were studied by electron spin resonance (ESR) spectroscopy. The crosslinked PTFE specimens with different crosslinking density were prepared by electron beam irradiation ih the molten state. The ESR spectra observed in the irradiated crosslinked PTFE are much different from those in non-crosslinked PTFE (virgin); a broad singlet component increases with increasing the crosslinking density, G-value of radicals is much higher in crosslinked PTFE than in non-crosslinked one. Free radicals related to the broad component are trapped in the non-crystalline region of crosslinked PTFE and rather stable at room temperature, whereas radicals trapped in amorphous non-crosslinked PTFE are unstable at room temperature. It is thought that most of free radicals trapped in the crosslinked PTFE are formed in the crosslinked amorphous region. The trapped radicals decays around 383 K (110 degrees C) due to the molecular motion of alpha-relaxation. (C) 1997 Elsevier Science Ltd.

引用

页码：601 / 606

页数：6

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