The synthesis, chemical characterization and optical properties of 2-(1-naphthyl)-4-vinyl-5-phenyloxazole (vNPO) and 2-(1-naphthyl)-4-allyl-5-phenyloxazole (allylNPO) monomers are reported. Starting with the organic fluor 2-(1-naphthyl)-5-phenyloxazole (alpha NPO), the vNPO and allylNPO monomers were synthesized using Stille coupling followed by purification. The final products were obtained with yields of similar to 95% and similar to 55% for vNPO and allylNPO. The absorption/emission spectra of alpha NPO, vNPO and allylNPO revealed that vNPO has the largest red-shifted in emission with an average wavelength of similar to 420 nm, which is an advantage for increasing photomultiplier tube sensitivity without the need to add a wavelength shifter. Stable scintillating resin beads were prepared through copolymerization of the newly synthesized fluor monomers with styrene or 4-methylstyrene and divinylbenzene in the presence of toluene porogen. The resin beads were chemically stable and retained the ability to scintillate efficiently after energy deposition of beta particles from Tc-99. This result indicates efficient energy transfer occurs from the base polymer to the covalently attached fluors with subsequent fluorescence in the presence of ionizing radiation.
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