Evaluation of residual lifetime of LDPE degraded radiation by time-temperature superposition method

Author

Kim, Ki-Yup ; Lee, Chung ; Ryu, Boo-Hyung ; Lim, Kee-Joe

Author_Institution

Korea Atomic Energy Res. Inst., South Korea

fYear

2001

fDate

2001

Firstpage

130

Lastpage

133

Abstract

A novel method has been proposed to determine the residual lifetime of low density polyethylene (LDPE) by time-temperature superposition (TTS) using a dynamic mechanical analyzer (DMA). The principle of this new method is to detect the change in response of polymeric materials to multi-frequency dynamic loading over a glass transition interval. LDPE was irradiated with gamma rays up to 1000 kGy at a dose rate of 5 kGy/hr in the presence of air at room temperature. The glass transition temperatures of irradiated samples were tested and compared with TGA and DMA methods. The inter-relationship between TGA and TTS methods for lifetime prediction was investigated. For radiation degradation of polymeric materials, TTS method can be a useful tool to predict the residual lifetime

Keywords

dynamic response; elastic moduli; gamma-ray effects; glass transition; insulation testing; life testing; polyethylene insulation; stress relaxation; thermal analysis; 1000 kGy; DMA; LDPE; TGA; TTS; dynamic mechanical analyzer; gamma ray irradiation; glass transition interval; mechanical loss modulus; multi-frequency dynamic loading; radiation degradation; reduced stress-relaxation curves; residual lifetime; room temperature; time-temperature superposition; Atomic measurements; Elasticity; Glass; Organic materials; Plastic insulation; Polyethylene; Polymers; Speech synthesis; Temperature dependence; Thermal degradation;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Insulating Materials, 2001. (ISEIM 2001). Proceedings of 2001 International Symposium on

Conference_Location

Himeji

Print_ISBN

4-88686-053-2

Type

conf

DOI

10.1109/ISEIM.2001.973584

Filename

973584