Radical formation in polydimethylsiloxanes and polydimethyldiphenylsiloxanes studied by the ESR spintrap technique

The radicals formed by gamma -irradiation of solid polydimethylsiloxanes and polydimethylsiloxanes containing 20 mol% diphenylsiloxane units were investigated by the spintrap technique using 2,4,6-tri-t-butylnitrosobenzene (BNB). After irradiation in vacuum at 77 or 293 K the spin adducts of the radicals could be identified. In the polydimethylsiloxanes containing diphenylsiloxane units no spin adducts originating from radicals at the phenyl group were detected.