Degradation of Silicone Rubber Analyzed by Instrumental Analyses and Dielectric Spectroscopy

  • Yoshimichi OhkiEmail author
  • Naoshi Hirai
  • Daomin Min
  • Liuqing Yang
  • Shengtao Li
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Silicone rubber (SiR) was gamma irradiated at 125, 145 and 185 °C or thermally aged at 220, 250 and 280 °C and the resultant changes in performance were evaluated. It has become clear from instrumental analyses that crosslinking via oxidation of silicon atoms and chain scission are induced by gamma rays. Furthermore, from the temperature dependence of real relative permittivity at high frequencies, the thermal expansion coefficient was found to become smaller with the increase in dose. These results can be understood well by the chemical and structural changes in SiR induced by the degradation.


Degradation Aging Complex permittivity Gamma rays SiR High temperature 


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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • Yoshimichi Ohki
    • 1
    • 2
    • 3
    Email author
  • Naoshi Hirai
    • 2
  • Daomin Min
    • 2
    • 3
  • Liuqing Yang
    • 2
    • 3
  • Shengtao Li
    • 3
  1. 1.Department of Electrical Engineering and BioscienceWaseda UniversityShinjuku, TokyoJapan
  2. 2.Research Institute for Materials Science and Technology, Waseda UniversityShinjuku, TokyoJapan
  3. 3.State Key Laboratory of Electrical Insulation and Power EquipmentXi’an Jiaotong UniversityXi’anChina

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