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Photochemical aspects in anthracene-containing cationic polyurethane

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: E. C. Buruiana, M. Olaru, B. C. Simionescu

Editorial: Eur. Polym. J., 43, p.1359-1371, 2007.

Rezumat:

The synthesis, characterization and photochemical properties of a new polyurethane cationomer (PUC–AN) with
anthracene chromophore groups attached on the quaternary ammonium units is reported and compared to those of a model
compound (AN) carrying the same moiety. PUC–AN synthesis implied the quaternization reaction with 9-chloromethylanthracene
of the tertiary amine of one precursor polymer based on poly(tetramethylene oxide) diol of 2000 average molecular
weight, tolylene-2,4-diisocyanate (as 2,4- and 2,6-TDI, 80:20 v/v isomers mixture), N-methyldiethanol amine and terephthalaldehyd-
bis(3-hydroxymethylphenylimine) in a molar ratio of 1:3:1:1. The fluorescence spectra of the anthracene structure
indicates that the synthesized compounds present different shifts in solution and in the solid state, their photochemical
behavior being influenced by monomer and excimer emission. The photophysical investigations revealed that such structures
can function as fluorescent chemosensors for transitional metals, showing a fluorescence quenching in the presence
of different metal ions (UO2þ 2 , Fe3+, Cu2+). The quenching mechanisms for PUC–AN and the corresponding model compound
(AN) are assigned to electron transfer and/or energy transfer processes of Dexter type.

Cuvinte cheie: Polyurethane cationomer; Anthracene; Excimer emission; UV/Vis; Photochemistry