SYNTHESIS AND CHARACTERIZATION OF WAVELENGTH-SHIFTING MONOMERS AND POLYMERS BASED ON 3-HYDROXYFLAVONE

The synthesis of novel fluorescent polymers containing 3-hydroxyflavone (3HF) as a pendant group is described. Monomers prepared for radical bulk and solution polymerization include 3-hydroxy-4'-ethenylflavone (V3HF), 3-hydroxy-4'-(1-methylethenyl)flavone (MV3HF),and 3-hydroxy-4'-(1-phenylethenyl)flavone (ST3HF). All monomers were synthesized by a modification of the Algar-Flynn-Oyamada route generally used for flavonols. Homopolymers of V3HF and styrene copolymers of V3HF and MV3HF were characterized by molecular weight studies and DSC/TGA, which indicated higher glass transition temperatures and similar thermal stabilities compared to polystyrene. Both monomers and polymers exhibited spectral properties that were similar to 3HF proper, including a very large (>180 nm) red shift of absorbed light due to an intramolecular proton-transfer mechanism, making them suitable for use as radiation-hard intrinsic scintillators for the detection of high-energy radiation.