ESR Spectra of γ-irradiated Linear Aliphatic Polyesters

The ESR spectra of γ-irradiated linear aliphatic polyesters (2.2, 2.4, 2.6, 2.7, 2.8 and 6.8 polymer) have been measured at various temperatures ranging from 77°K to room temperature. Two types of spectra are obtained in these polyesters except for 2.2 polymer. The first, the six-line spectrum obtained at low temperatures was relatively short-lived and increased in signal intensity with increasing methylene groups of these polyesters. The well-resolved, second, five-line spectrum is stable even at room temperature in comparison with the former. The possible structures of two radicals were discussed.