硅橡胶泡沫伽马辐照后结构和元素分布研究

在密闭的氮气气氛下,用伽马射线辐照聚二甲基硅橡胶泡沫,采用全反射红外光谱(ATR)和X射线光电子能谱(XPS)对辐照后的化学结构和元素含量变化进行了表征.结果表明:化学结构单元Si-CH3最容易受到伽马射线的影响,在低的辐照剂量下表面Si-CH3成分随着辐照剂量增加而减小；高剂量下材料的元素分布发生了变化,近表面C元素含量要比泡沫体中部的C元素含量高.因此,在密闭环境下辐照老化后的硅橡胶泡沫的表面性能和体内性能存在差异.

Research on Structure and Element Distribution of Polydimethysiloxane Rubber Foams After Gamma Irradiation

Polydimethylsiloxane rubber foam was irradiated in sealed nitrogen,atmosphere by gamma ray, and then the chemical structure and element content of the irradiated foams were characterized by infrared attenuated total reflectance spectroscopy （ATR） and X-ray induced photoelectron spectroscopy （XPS）.The results show that the Si-- CH3 bond in chemical structure is affected most easily by gamma ray, and the content of Si--CH3 in surface chemical structure decreases with the radiation dose increasing under the low radiation dose condition. The element distribution of the materials changes, and the content of carbon closed to the surface is higher than that in the middle of the foams under the high radiation dose condition. So the properties on the surface are different from the properties in the body of polydimethylsiloxane rubber foam after radiation aging in sealed nitrogen atmosphere.