Influence of luminescent additives on the optical and luminescent properties of organic polymers

In this paper, studies of the influence of luminescence additives on the optical and luminescence properties of polyurethane based organic polymers are presented. Absorption and transmittance spectra reveal a decrease of transmittance with increasing filler concentration. In the X-ray excited luminescence spectra of nanocomposite samples with an inorganic filler, no bands, related to self-trapped exciton (STE) or core-valence luminescence (CVL) luminescence of barium fluoride are observed. This is due to the overlap of the organic phosphor absorption band and barium fluoride emission band. Measurements of decay time constant also reveal no long component of STE luminescence. This may be due to non-radiative energy exchange between barium fluoride and PPO.