Evaluation of Radiation Degradation or Crosslinked Polyethylene using TGA

TGA를 이용한 가교폴리에틸렌의 방사선 열화 평가

  • Lee, Chung (Department of Electrical, Chungbuk National University) ;
  • Kim, Ki-Yup (Korea Atomic Energy Research Institute) ;
  • Ryu, Boo-Hyung (Department of Safety Engineering, Dongguk University) ;
  • Lim, Kee-Joe (Department of Electrical, Chungbuk National University)
  • 이청 (충북대학교 전기공학과) ;
  • 김기엽 (한국원자력연구소 방사선응용연구팀) ;
  • 류부형 (동국대학교 안전공학과) ;
  • 임기조 (충북대학교 전기공학과)
  • Published : 2003.06.01

Abstract

Radiation degradation of crosslinked polyethylene(XLPE) was investigated using thermogravimetric analysis(TGA), The results of TGA were compared with FT-IR, melting temperature, oxidation induction time, and elongation at break on the XLPE exposed by $\gamma$-ray. 5% decomposition temperature of $\gamma$-ray irradiated XLPE showed similar tendencies with the case of elongation at break. Both properties agreed below 1000 KGy, however, did not show any remarkable characteristics above 1000 kGy, these properties can be useful to evaluate the radiation degradation of XLPE for only low irradiated region. Above 1000 kGy, the thermal decomposition activation energy showed decreased, on the contrary, increasing below 1000 kGy. Compared with FT-IR spectrum of irradiated XLPE, it was confirmed that the oxidation reaction was still occurring below 1000 kGy. Radiation degradation of XLPE was dependent upon the irradiation doses, TGA can be a useful tool to evaluate the degradation.

Keywords

radiation degradation;XLPE;TGA;DSC;activation energy

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