Epoxy Based Scintillators for Beta Radiation Detection

This article describes the design, development, fabrication, and validation of epoxy scintillators (ESs) based on Araldite (C
₁₈
H
₂₁
ClO
₃
), Jeffamine (C
₃
H
₁₀
N
₂
O), and scintillation fluorophores. ESs of 0.5 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 optimization. Radioluminescence (RL) spectra of the samples with different percentages 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 ES showed maximum RL. Scintillator properties of the ESs are compared with a commercial polystyrene-based plastic scintillator (PS) EJ 212 (thickness-
$500~\mu \text{m}$
). The fluorescence lifetime measurement of ES has been found to be 1.68 ns with a 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 ESs have been taken for beta radiation using
⁹⁰
Sr-
⁹⁰
Y. The results showed that the ESs performed similarly to EJ 212 PS.