Investigation on Insulating Degradation of Heat Resistant Organic Materials by Irradiation

在本研究中，对耐热有机材料伽马射线辐射的物理学和非电击穿特性进行了研究。所用的样品有全氟烷基（PFA）、氟乙基丙基（FEP）、聚乙基酮（PEEK）和环氧树脂（EPX）。辐射由伽马射线（0.258 kC/kg·h）在空气温度下携带。根据物理化学分析的结果，发现了PFA和FEP的自由基物数量，在0.01 MGY辐射和氧化反应中连续发射。A structure of PEEK didn't change up to 5 MGy irradiation。Dielectric breakdown characteristics of PFA and FEP films decreased with increasing irradiation dose， especially changed at 0.15 MGy irradiation rapidly。但是，那些PEEK电影并没有改变到5MGY辐射。关于另一方，EPX的非电击穿特征倾向于在2MGY辐照度下降。下一步，PFA电缆快速降解的非电击穿特征在0.2MGY辐照度，但是，那些FEP电缆的非电击穿特征没有改变到0.2MGY辐照度。Dielectric breakdown characteristics of PEEK cable didn't change up to 5 MGy irradiation.Irradiation resistant characteristics of EPX existed between FEP and PEEK。Irradiation dose that dielectric breakdown characteristics of PFA and FEP cables （厚度：0.5 mm） decreased rapidly与PFA and FEP films （厚度：50 um）高度比较。这一事实表明，氧化降解的深度是从样品表面上明显的。

In this study, physicochemical and dielectric breakdown characteristics of heat resistant organic materials gamma ray-irradiated were investigated.Samples used are perfluoroalkoxy (PFA), fluorinated-ethylene-propylene (FEP), polyetheretherketone (PEEK) and epoxy resin (EPX). Irradiation was carried out by gamma ray (0.258kC/kg・h) in air at room temperature.From results of physicochemical analyses, it was found that the amount of free radicals of PFA and FEP increased at 0.01MGy irradiation and oxidation reactions occurred by chain scission. A structure of PEEK didn't change up to 5MGy irradiation.Dielectric breakdown characteristics of PFA and FEP films decreased with increasing irradiation dose, especially changed at 0.15MGy irradiation rapidly. But, those of PEEK film didn't change up to 5MGy irradiation. On the other hand, dielectric breakdown characteristics of EPX tended to decrease at 2MGy irradiation.Next, dielectric breakdown characteristics of PFA cable decreased rapidly at 0.2MGy irradiation, but, those of FEP cable didn't change up to 0.2MGy irradiation. Dielectric breakdown characteristics of PEEK cable didn't change up to 5MGy irradiation.Irradiation resistant characteristics of EPX existed between FEP and PEEK. Irradiation dose that dielectric breakdown characteristics of PFA and FEP cables (thickness : 0.5mm) decreased rapidly was high compared with PFA and FEP films (thickness : 50um). This fact indicates the depth of oxidation degradation is shallow from the surface of samples.