ESR studies on poly(vinyl chloride) irradiated at medium and high doses

Room temperature gamma irradiation at medium (1–100 kGy) or high (0.9–25 MGy) doses induces different radicals into pure or industrial poly(vinyl chloride) (PVC); the various ESR signals differ by their shapes and/or values of their g-factors and/or peak-to-peak widths but do not give precise information on the chemical structures of the different radicals as the spectra are only poorly resolved. However, looking at the ESR parameters of the different signals and their evolution during natural ageing of the samples, allows us to make correlations between the radio-induced lines in industrial PVC and the ones induced in pure PVC or in PVC additives.