| Abstract
| - Decay of ions trapped in γ-irradiated poly(methyl methacrylate) (PMMA)-containing ion scavengers wasexamined. Cations in PMMA migrate through diffusion and by a hopping transfer of the charge. They encounteranions, combine, and thereby decay. The diffusion of cations was confirmed by a comparison of decay ofions in PMMA-containing pyrene and that in a copolymer of methyl methacrylate and 1-pyrenylmethylmethacrylate. Cations in the former sample decay faster than those in the latter sample. The ions in thecopolymer are chemically bonded to the polymer chains, preventing the diffusion of the ions. However, thedependence of the decay of the ions on the concentration of pyrenyl groups indicated that the ions decaythrough a hopping transfer of the charge on pyrenyl groups. The hopping transfer was suppressed bytriphenylamine. The suppression is ascribed to structural difference in neutral triphenylamine and its cation.Anions in PMMA are ketyl-type anions at the side chains of the polymer. Their migration is suppressed,since they are connected to the polymer chains and the structures of the neutral state and its anion are different.
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