A study of the effects of gamma irradiation on the structural and mechanical properties of polyvinyl butyral film

In the present research, polyvinyl butyral film was prepared and irradiated by gamma-ray at various doses up to 250 kGy. Then, the effects of irradiation on the PVB were studied through the tensile test, FTIR, 1H-NMR and AFM techniques. The results of tensile tests show the existence of 'necking' up to 100 kGy and an increase in the toughness up to 70 kGy. Structural study by spectroscopic techniques show the formation of new groups as a result of increased conjugated double bonds. At higher doses, however, the polymer began to decompose due to degradation of the main chains, which led to reduced mechanical strength. Finally, AFM examination of the samples revealed less rough surface by irradiation.