Synthesis and characterization of rare earth metal‐containing polymers. I. Fluorescent properties of ionomers containing Dy³⁺, Er³⁺, Eu³⁺, and Sm³⁺

Abstract

Rare earth metal (Dy3+, Er3+, Eu3+, and Sm3+) salts of copolymers of methyl methacrylate–methacrylic acid, styrene–acrylic acid, 1‐vinylnaphthalene–acrylic acid and 1‐vinylanthracene–styrene–acrylic acid were prepared. The fluorescence of these polymer salts under ultraviolet excitation was investigated. The fluorescent intensity of polymer–Eu3+ films varied with film thickness because of incomplete absorption of exciting light, hence most of the measurements were made on pressed fine powders. The fluorescent intensity of mixed samples of Eu(III) acetate in a polymer matrix increased linearly with Eu content. However, the Eu3+–polymer complex system displayed typical concentration‐quenching behavior, reaching a maximum at 4–5 wt % Eu and decreasing with further increases in Eu content. This suggests that the ionomer contains ionic aggregates, in agreement with a recently proposed model. Such aggregates would create locally high Eu ion concentrations, whose interactions lead to concentration quenching at low nominal concentrations. The fluorescent intensity of the acrylic copolymers decrassed in the order methacrylate > styrene > naphthalene > anthracene. This sequence is explained by incrasing competition for the exciting light by the aromatic groups with negligible energy transfer from the aromatic groups to the Eu3+ ions. This is also consistent with the hypothesis that the ionic regions of the polymer are segregated.

Energy Transfer From Copolymers of Styrene-Maleic Acid to Eu(iii) Ions in Tetrahydrofuran

“…This result may be considered to provide a supporting evidence to the proposal that ioncontaining polymers have ionic aggregates in which the local concentration of metal ions is larger than the overall range concentration [7].…”

“…In the present system, however, an increase in the concentration of Eu(II[) is suspected to increase the polymer chain coiling [6,7], which increases the probability of forming the sandwich conformation needed for excimer formation. This result may be considered to provide a supporting evidence to the proposal that ioncontaining polymers have ionic aggregates in which the local concentration of metal ions is larger than the overall range concentration [7].…”

Fluorescence, ion binding, and viscosity properties of poly[2- and 4-vinylpyridine]s in methanol and in sulfuric acid

“…3 ion, respectively. 12 The fluorescence intensities of Tb 3ϩ in systems containing high-molecular weight ligands P4VP and P2VP were much greater than that of 4MP and decreased in the order of P4VP Ͼ P2VP Ͼ 4MP. When a large excess of 4MP was added into TbCl 3 methanol solution (4MP/Tb 3ϩ Ͼ 20), the increase in fluorescence intensity of Tb 3ϩ was not observed.…”

Fluorescent properties of polymer–rare earth ion complexes. II. Poly(acrylic acid‐co‐acrylamide)–rare earth ion complexes

“…Equation (1) shows that by adjusting r, and r2, a series of uniform copolymer with various composition can be synthesized. The copolymerization of acrylic acid and acrylamide is such an example.…”