Degradation in Kapton foil after gamma irradiation at low fluence is presented. These foils are irradiated for doses ranging from 10 to 500 kGy. The irradiated (10–50 kGy) Kapton foils show an uniform increase in visible absorption from 500 to 800 nm that decreases for further irradiation up to 500 kGy. FTIR spectra show first decrease in the absorption for all the peaks from 10 to 50 kGy and then increase from 50 to 500 kGy irradiation. Absorption of water moisture has also been observed at low fluence (∼10 kGy) that decreases at higher doses of irradiation. Difference spectra of Kapton before and after irradiation show chain scission at low fluence. This chain scission creates various types of defects, radicals and color centers. The reorganization/cross-linking of bonds is found at higher doses (>50 kGy) of irradiation, where the moisture absorbed at low doses of irradiation plays an important role. The Kapton foil shows opposite nature in terms of chain scission and cross-linking in comparison to the Poly (methyl methacrylate) irradiated in similar conditions.

中文翻译：

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低通量伽马辐照后 Kapton 箔的降解行为研究

介绍了低通量伽马辐照后 Kapton 箔的降解。这些箔的辐照剂量范围为 10 至 500 kGy。辐照后的 (10–50 kGy) Kapton 箔显示可见光吸收从 500 到 800 nm 均匀增加，进一步辐照至 500 kGy 时会降低。FTIR 光谱显示所有峰的吸收首先从 10 kGy 降低到 50 kGy，然后从 50 kGy 辐射增加到 500 kGy。在低通量（~10 kGy）下也观察到水分的吸收，这在较高辐射剂量下会降低。辐照前后 Kapton 的差异光谱显示在低通量下断链。这种断链会产生各种类型的缺陷、自由基和色心。在更高剂量（> 50 kGy）的辐射下发现键的重组/交联，其中在低剂量辐射下吸收的水分起着重要作用。与在类似条件下辐照的聚（甲基丙烯酸甲酯）相比，Kapton 箔在断链和交联方面表现出相反的性质。