Degradation of poly(carbonate urethane) by gamma irradiation

Ozdemir, T.
Usanmaz, Ali
Poly(carbonate urethane) (PCU), is a valuable commercial engineering polymer. In order to understand the possible use of PCU in radioactive waste management as a solidifying agent or as a disposal container, radiation stability of the PCU is studied by Co-60 gamma irradiations at two different dose rates of 1540 and 82.8 Gy/h. The total dose of irradiation was up to 6.24 MGy. Degradation nature was tested by studying the changes in mechanical and thermal properties with rate and total dose of irradiation. Ultimate tensile strength and toughness first increased and then decreased with the irradiation dose. Half value dose (HVD) for elongation was 4010 kGy and for tensile strength 60 10 kGy at the dose rate of 1540 Gy/h. The non-irradiated PCU transparent color changed to yellow and then brown with increased irradiation dose. The FTIR spectral analysis showed a random scission of polymer with irradiation. From the experimental observation, it was shown that PCU can be used for embedding radioactive waste for about 300 years.


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Citation Formats
T. Ozdemir and A. Usanmaz, “Degradation of poly(carbonate urethane) by gamma irradiation,” RADIATION PHYSICS AND CHEMISTRY, pp. 1069–1074, 2007, Accessed: 00, 2020. [Online]. Available: