Preparation And Properties Of Several Polymers Functionalized With Schiff Base And Their Rare Earth Complexes

The luminescence properties of rare earth organic complexes have been widely applied in numerous fields, which have been got intensively attention. Based on the synthesis of new type of rare earth polymer luminescent material, three series of complexes containing functional groups of schiff base were constructed, and the luminescent properties of these complexes were further investigateded in this work. Main researches and conclusions were as follows:1. With styrene, butyl acrylate, salicylaldehyde and hydrazine hydrate as raw materials, a series of polyphenylethylene-butyl acrylate PSCBS with schiff base functional pendant groups were prepared. A series of luminescent complexes with preliminary designing structure and functional properties were synthesized by further coordinated with Eu3+/Y3+ ion. The composition, structure, and thermostability of the ligands and the complexes were characterized by FTIR, UV-Vis, elemental analysis, thermogravimetric analysis, and the luminescence properties of the complexes were investigated. The results showed that the prepared complexes had good solubility, film-forming properties and thermostability. The polymer PSCBS showed good coordinating ability after introduced the functional groups of schiff base because the N of schiff base groups, the O of carbonyl and hydroxyl could all participate in the coordinating reaction. The ligands had strong absorption in the UV region, and the main energy absorptions of the complexes were attributed to Ï€â†'Ï€* transition of the benzene ring and the nâ†'Ï€* transition of the-C=N- of the Schiff base. The complex exhibited the characteristic spectra of ligands and Eu3+ under visible light excited, and the fluorescence intensity of the complexes reached maximum with butyl acrylate monomer and styrene monomer at the mole ratio of 1:1.2. Using 1, 4-Phthalaldehyde, hydrazine hydrate, and salicylaldehyde as raw materials, a series of conjugated polymers PTF with schiff base backbone were obtained by condensation reaction, and a series of rare earth-polymer complexes PTF-Eu(III) /Y(III) were successfully synthesized by further coordinated with Eu3+/Yb3+ ion. The composition, structure, and thermostability of the ligands and the complexes were characterized by FTIR, UV-Vis, elemental analysis, thermogravimetric analysis, and the luminescence properties of the complexes were studied. The results showed that the prepared complexes had better solubility and thermostability. The characteristics of energy bands had greatly changed after introduced the Ï€-conjugate schiff base constructure into the main chain of the polymer, which was beneficial to improve the coordinating ability of the polymer ligands. The ligands had strong absorption in the UV region, and the main energy absorptions of the complexes were assigned to Ï€â†'Ï€* transition of the benzene ring and the nâ†'Ï€* transition of the-C=N- of the Schiff base. The complex exhibited the characteristic spectra of ligands and Eu3+ under visible light excitation, and the PTF2- Eu(III) /Y(III) showed the maximum fluorescence intensity.3. Using dimethyl terephthalate, hydrazine hydrate, and salicylaldehyde as raw materials, a salicylaldehyde-terminated polymer PBT with acyl hydrazone schiff base backbone was synthesized by condensation reaction. A rare earth-poly schiff base complex PBT-Eu(III) /Y(III) was successfully synthesized by further coordinated with Eu3+/Y3+ ion. The composition, structure, and thermostability of the ligand and complexe were characterized by FTIR, UV-Vis, elemental analysis, thermogravimetric analysis, and the luminescence property was studied. The results showed that the prepared complexes had better solubility and thermostability. The salisylic aldehyde groupe of the terminate chain and the acylhydrazone structure of polymer backbone can effectively improve the coordinating ability. The ligands had strong absorption in the UV region, and the main energy absorptions of the complex were Ï€â†'Ï€* transition of the benzene ring and the nâ†'Ï€* transition of the-C=N- of the schiff base. The complex with nice luminous performance exhibited the characteristic spectra of ligands and Eu3+ under visible light excitation, which indicated that the efficacious energy transmition had occurred between the PBT and rare earth ions.