Solvation effects on spectral and photophysical properties of phenalenone dyes in polyurethane polymers

Spectral and photophysical properties of several phenalenone dyes were investigated in the dependence on a type of the polyurethane polymer matrix. The increase in polarity of the solid-state medium was shown to shift absorption and luminescence spectra to the low energy side. Effects of the substituents in the phenalenone chromophore on a Stokes shift value were studied. Photophysical properties of phenalenones were found out to be significantly dependent on the polymerization method of polymer matrices. Considerable growth in photostability of organic dyes was observed when the dyes were bonded covalently with a polymer chain.