Active Structural Materials for Low Background Experiments

Progress in the field of neutrino physics, including searches for neutrinoless double beta decay ($0\nu\beta\beta$) and neutrino oscillation measurements, places extreme demands for ultra-low background sensitivities. These improvements can be achieved by replacing inactive structural components with transparent, radio-pure plastic scintillators. These structural scintillating components surround the detector with a low background material and serve as an active veto, discriminating internal events of interest from external background events. Poly(ethylene-2,6-naphthalate) (PEN) has been identified as an ideal material for structural scintillator components as it has a significant yield strength and scintillates in the 400 nm region. A synthesis method has been developed to optimize optical properties and limit exposure to radio-impurities. This presentation will provide an update on the synthesis and characterization of PEN and PEN derivatives, as well as provide examples of applications for future ton-scale 0$\nu\beta\beta$ experiments.