γ線照射 Polytetrafluoroethylene の核磁気共鳴吸収 (I)

抄録

Molecular motion in gamma-irradiated polytetrafluoroethylene is investigated with the nuclear magnetic resonance method. With ⁶⁰Co as radiation source and 10⁸R as total exposure dose, irradiation effects on the line shape of F¹⁹ nuclei are investigated, whereby change of motional narrowing in the narrow line width, room temperature transition in the second moment, and increase in crystallinity were observed. Especially, a specimen, heated at 300°C for four hours after irradiation, showed a remarkable increase of crystallinity. These results are discussed in some detail. The increase in crystallinity is ascribed to the decrease in molecular weight, and the change in molecular motions to the change in molecular arrangement.