Epoxy Based Scintillators for Beta Radiation Detection

This paper describes the design, development, fabrication and validation of epoxy scintillators based on Araldite (C 18 H 21 ClO 3 ), Jeffamine (C 3 H 10 N 2 O) and scintillation fluorophores. Epoxy scintillators (ES) of 0.5 mm and 10 mm thicknesses are made by manual mixing and drying of constituent liquid-based chemicals at various concentrations of 2,5-Diphenyloxazole (PPO) or p-Terphenyl (PT) and 1,4-bis(5-phenyloxazol-2-yl) benzene (POPOP) for optimisation. Radioluminescence (RL) spectra of the samples with different percentage of primary and secondary fluorophores are measured with 90 Sr- 90 Y beta source. Among the studied concentrations, 2.8 wt% of PT and 0.28 wt% of POPOP dyed epoxy scintillator showed maximum RL. Scintillator properties of the epoxy scintillators are compared with commercial polystyrene based plastic scintillator EJ 212 (thickness-500 μm). The fluorescence lifetime measurement of epoxy scintillator has found to be 1.68 ns with pulsed laser source of 371 nm excitation. Further improvements in the scintillation efficiency of ES have been achieved with BaFBr:Eu 2+ or Gd(BO 2 ) 3 :Tb 3+ micro phosphor loading. Pulse height spectra of the synthesized epoxy scintillators have been taken for beta radiation using 90 Sr- 90 Y. The results showed that the epoxy scintillators performed similar to EJ 212 plastic scintillator.