A study on the effects of gamma radiation on the properties of polycarbonate

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2011

Author

Kinalır, Kerim Gökhan

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This thesis aims to investigate the effects of gamma radiation on the properties of polycarbonate, an engineering thermoplastic which has a wide range of applications. A commercial grade polycarbonate resin, after being shaped into the required specimen forms by injection molding, was irradiated with different doses up to 180 kGy. Tensile strength was found to decrease with increasing dose. The lowest values of tensile modulus, flexural modulus and flexural strength were obtained at 96 kGy, which is also the dose at which molecular weight values showed a minimum. No remarkable changes in Shore D hardness values and NMR spectra were observed. The ATR-FTIR spectra showed that irradiation was effective on carbonyl groups in the structure. The glass transition temperatures of the specimens irradiated up to the maximum dose were lower than those of the non-irradiated specimens. The onset of weight loss at lower temperatures and steeper weight loss behavior in the TGA curves indicated decreasing thermal stability of the polymer with increasing dose.

Subject Keywords

Gamma rays., Polymer Science and Technology.

URI

http://etd.lib.metu.edu.tr/upload/12613020/index.pdf
https://hdl.handle.net/11511/20448

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

K. G. Kinalır, “A study on the effects of gamma radiation on the properties of polycarbonate,” M.S. - Master of Science, Middle East Technical University, 2011.