Методом возникающих реагентов непосредственно в среде (поли)метилметакрилата (ПММА) синте-зированы квантовые точки ZnS : Cu, закрепленные в оптически прозрачной полимерной матрице. Свето-пропускание полимерных композиций в видимой области спектра достигает 92% (при толщине 5 мм). Фотолюминесценция ПММА/ZnS : Cu связана с дефектами кристаллической структуры ZnS и системой энергетических уровней, расположенных в запрещенной зоне сульфида цинка. Она зависит от концентрации ионов меди, перепоглощения излучения ZnS и ПММА, а также от других факторов.
The reaction of cadmium, manganese, and lead trifl uoroacetates with thioacetamide in methyl methacrylate yielded colloidal solutions of metal sulfi des with different Cd(II) : Mn(II) : Pb(II) molar ratios. The colloidal particles were separated from solutions and examined by electron microscopy. Glassy polymer composites poly(methyl methacrylate):Cd(Mn)S and poly(methyl methacrylate):Cd(Mn,Pb)S were prepared by thermal polymerization of methyl methacrylate in the bulk. The transmittance of the composites at wavelengths larger than 480 nm is 92% at the sample thickness of 0.40 cm. The luminescence of the composites in the visible range is associated with cadmium sulfi de. The corresponding absorption bands were recorded in the luminescence excitation spectra in the wavelength interval 300-450 nm. The effect of the matrix, Mn(II) and Pb(II) ions, and synthesis conditions on the absorption and luminescence properties of the composites was determined.
The absorption and fluorescence spectra and the lasing ability of aminocoumarin derivatives in thin polymer layers (0.5-0.8 µm) based on the copolymer methylmethacrylate with a methacrylic acid and the copolymer methylmethacrylate with glycidylmethacrylate formed by coating of optically transparent glass substrates have been studied. It is found that the intensity of absorption and luminescence as well as the lasing resource of coumarins are determined by the structure of the latter and by the nature of the polymer medium. Compositions based on the copolymer methylmethacrylate with glycidylmethacrylate and aminocoumarin derivatives with a fluorized methyl group at the 4th molecular position can be of interest in optical technologies (light transformers, amplifiers).Keywords: aminocoumarins in polymer films, spectral-luminescent properties, forced radiation, copolymers methylmethacrylate with methacrylic acid and methylmethacrylate with glycidylmethacrylate.Introduction. Coumarins relate to widely distributed luminescing laser dyes and are of interest for creating active solid-body media of the blue-green spectral range. In [1], the results of investigation of 17 aminocoumarins in solutions and a solid matrix of polymethylmethacrylate (PMMA) on pumping by the excimer XeCl laser radiation (λ pump = 308 nm) are presented. Out of the large group of coumarins investigated, the ethanol solutions of which are good laser media, only some of them are promising for creating active solid-body media of tunable lasers that emit in the blue-green spectral region. These are the coumarins with a fluorized methyl group in the 4th molecular position and coumarins with heteroaromatic substituents (benziazolyl-, benzoxazolyl-, benzimidozolyl-) in the 3rd position.The aim of the present work is to study the characteristic features of the spectral-luminescent properties (absorption and fluorescence spectra) precisely of these types of coumarins in thin polymer layers based on the copolymers of methylmethacrylate on optical excitation, to elucidate the lasing ability of coumarins in polymer films, and to carry out an analysis of the processes proceeding in a polymer-dye system.Experimental. The structural formulas of the coumarin molecules investigated in thin polymer films have the form
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