Europium-Containing Luminescent Composites Based on Lead(II)-Modified Poly(methylmethacrylate)

Composites based on poly(methylmethacrylate) (PMMA) and lead and europium salts, with the compositions PMMA/Pb(CF₃COO)₂ and PMMA/Pb(CF₃COO)₂,Eu(CF₃COO)₃, have been prepared by curing methylmethacrylate (MMA) based solutions via thermal radical block polymerization of MMA. The refractive index of MMA + Pb(CF₃COO)₂ solutions and the density of the PMMA/Pb(CF₃COO)₂ polymer composites have been shown to increase linearly as the Pb salt concentration increases to 83 wt % (40 wt % elemental Pb). The optical transmission of the composites at wavelengths above 450 nm and the highest lead and europium concentrations reaches 90% at sample thicknesses of up to 5 mm. The lead equivalent at a Pb(II) concentration of 40 wt % is 0.010. Photoluminescence in the PMMA/Pb(CF₃COO)₂,Eu(CF₃COO)₃ composites is due to Eu³⁺ electronic transitions from the ⁵D₀ metastable electron energy level to the ⁷F_j sublevels of the ground level. We have demonstrated the influence of lead(II) and europium(III) on the properties of the matrix and the influence of the matrix and Pb(II) on absorption and luminescence spectra of europium(III).