SOLVENT EFFECT ON THE PHOTOPHYSICS OF BISPHENOL-A-BASED POLYCARBONATEAND DIPHENYLCARBONATE

Polycarbonate and diphenylcarbonate exhibit an anomalous fluorescence emission with peak maximum around 350 nm in polar solvents that may be attributed to the association of diarylcarbonate moieties in a polar solvent cage. The red-shifted emission is attributed to intermolecular interactions in polar solvents and intramolecular interactions in pol ycarbonate. The photophysical behavior of polycarbonate and diphenylca rbonate is different from that of 1,3-diphenylpropane where a red-shif ted emission is due to excimers formed by phenyl groups separated by t hree carbon atoms and is independent of the polarity of the solvent.