The optical transmittance and pulse shape discrimination of polystyrene/poly(methyl methacrylate) based plastic scintillators

Polymethyl methacrylate (PMMA) is an optically transparent thermoplastic with favorable processing conditions. In this study, a series of plastic scintillators were prepared via thermal polymerization, and the impact of PMMA content on their transparency and pulse shape discrimination (PSD) ability was investigated. The fabricated samples, comprising a polystyrene (PS)-PMMA matrix, 30 wt% 2,5-diphenyloxazole (PPO), and 0.2 wt% 9,10-diphenylanthracene (DPA), exhibit high transparency with transmissivity ranging from 70.0% to 90.0%(above 415.0 nm) and demonstrate excellent n/γ discrimination capability. The transparency increases with higher PMMA content across the entire visible light spectrum. However, the PSD performance gradually deteriorates as the aromatic matrix is replaced by PMMA. The scintillator containing 20.0 wt% PMMA demonstrates the best stability in terms of PSD properties and relative light yields.

聚甲基丙烯酸甲酯（PMMA）是一种具有优良加工性能的光学透明热塑性塑料。本研究通过热聚合方法制备了一系列塑料闪烁体，并探究了PMMA含量对其透明度及脉冲形状鉴别（PSD）能力的影响。所制备的样品以聚苯乙烯（PS）-PMMA为基质，含30 wt%的2,5-二苯基恶唑（PPO）和0.2 wt%的9,10-二苯基蒽（DPA），在415.0 nm以上波长处的透光率为70.0%至90.0%，具有高透明度，且表现出优异的n/γ鉴别能力。在整个可见光范围内，透明度随PMMA含量的增加而提高；然而，随着芳香族基质被PMMA取代，PSD性能逐渐下降。含20.0 wt% PMMA的闪烁体在PSD性能和相对光输出方面表现出最佳稳定性。