Scintillation detectors based on poly-2,4-dimethylstyrene: structural peculiarities and radiation damage

Scintillation detectors based on poly-2,4-dimethyl styrene (P-2,4-DMS) are studied. Investigated is the influence of two methyl groups present in the benzene ring on the energy, spectral and structural characteristics of the polymer. The said factors are assumed to result in the detectors high light output and radiation resistance. It is shown that under radiolysis (77 K) the radiation yield of the paramagnetic centers of P-2,4-DMS exceeds that of polystyrene (PST) by ~1.5 times. Unlike PST film, the luminescence spectra of P-2,4-DMS are characterized by the presence of both excimer (320-340 nm) and monomer (292 nm) bands. Revealed are the distinctions in the nature of the optical characteristics of macroradicals and the efficiency of energy transfer in gamma-irradiated PST and P-2,4-DMS scintillators. The relation between the supermolecular structure of the polymers and the interaction of their macroradicals with molecular O₂ is stated