Materiales poliméricos con aplicación fotodegradativa

R. SPADA; M. L. GOMEZ; R. E. PALACIOS

Santa Fé

Congreso; XIII Congreso Internacional de Metalurgia y Materiales - IBEROMAT 2014; 2014

Universidad Nacional del Litoral

The design and development of polymeric materials containing photosensitizing is an area of great interest in organic photochemistry. By appropriate design the polymeric microenvironment can provide properties such as selective accumulation of substrates, stabilization of photo-excited species and energy transfer from the polymeric matrix to the sensitizer. On the other hand, tricarbonyl Re(I) complexes have aroused great interest both for their luminescent properties and for its utilization in photocatalytic processes. Of particular interest is the ability of these complexes to generate singlet oxygen due to their potential use in environmental chemistry, biological inactivation and photodynamic therapy.The synthesis of complexes of Re(I) with bidentate ligands of type P,N (amine-phosphine) and N,N (1,10-phenanthroline) was carried out; and the produced complexes were incorporated into silsesquioxane films bridged with pendant dodecyl groups. Films were synthesized with and without dopants. The films were characterized by UV-visible spectroscopy absorption, stationary and time resolved emission. A homogeneous dispersion of the complex was achieved in the polymer matrix, resulting in an optically homogeneous material, where the photophysical properties of the complexes were not altered.The ability of these materials to generate singlet oxygen was evaluated indirectly through kinetic studies of dimethylanthracene degradation and directly by measuring the singlet oxygen luminescence. The results showed that the doped materials produce significant quantity of singlet oxygen upon photoirradiation in the visible zone of the electromagnetic spectrum. In particular the doped material with the complex (N,N)Re(CO)3Br is the one that produces more singlet oxygen. Based on the obtained results we propose to continue with the development of these materials in order to use their properties in the implementation of solid-liquid strategies for photoinduced degradation of organic pollutants in aqueous media.