Infrared study of combined effect of γ‐radiation and elevated temperature on poly(vinyl chloride)

摘要

AbstractInfrared absorption spectroscopy has been used to investigate the combined effect of γ‐radiation and heat on poly(vinyl chloride) (PVC). The recorded spectra showed that exposure of PVC samples to gamma doses from 0.5 to 15 Mrad results in remarkable changes in the absorbances of their absorption bands. Also, the exposure to doses from 3 to 15 Mrad results in an appearance of a CO band at 1720 cm−1and OH band at 3450 cm−1. The nature of the formation of these bands was discussed in terms of peroxide‐mediated oxidative degradation mechanism. Moreover, it was found that heat treatment of PVC samples over the temperature range 25–180°C causes no noticeable changes in their spectra apart from slight changes in the absorbances of the bands. On other hand, it was found that heat treatment of the irradiated samples causes considerable increase in the intensity of the CO band. In addition to the well‐defined and sharp band appearing at 1720 cm−1, the spectra of the samples irradiated with 10 and 15 Mrad exhibited two bands at 1070 and 1120 cm−1. The obtained data led also to the conclusion that the CCl bands cannot be used as a measur