| The material of polyurethane-acrylate (PUA) has been applied extensively in the fields of engineering materials due to its characteristics of corrosion-resistant, high temperature resistance, good toughness, high transparency, high precision, etc. Various PUA materias with different mechanical properties can be obtained by exact designing molecular structure of product. Finally, the function of the materials was realized.The rare earth elements have unique electronic structure and rich electronic energy levels which determine them have good fluorescence properties or magnetic properties. But the low luminescence efficiency of rare earth ions is a problem. In order to solve this problem, we chose the organic ligand which has a high absorption coefficient to form the organic complex. The organic ligand can absorb light energy. Then the energy can be passed to the rare earth ions which can emit characteristic fluorescence, thus an important class of fluorescent material is obtained. Considering these respects mentioned above, in this dissertation, polyurethane-acrylate material were selected as matrices incorporating the rare earth complexes with different predestined organic ligands to construct novel functional composites by employing doping-type and bonding-type, respectively. The main contents including four chapters are as follows:(1) The rare earth complexes [Tb(L1)(phen)]∞was prepared through high-temperature hydrothermal method, in which L1 is 5-hydroxy-isophthalic acid-based anionic ligands, phen is phenanthroline. The crystal structure of the obtained complex was analyzed. The rare earth TbIII / polyurethane green fluorescent composite materials were prepared by the complex being doped into PUA. The properties of the composite materical were characterized, such as thermal properties, mechanical properties, fluorescence properties and dynamic mechanical properties. The results showed that composite material has good green fluorescence properties. Fluorescence properties of composite material become more and more strongger with the RE content increasing. When the rare earth content is 7%, the composite material can still send a strong green fluorescence, no fluorescence quenching. Heat resistance of materials has increased with the increase of RE content. The glass transition temperature increases at first and then decreases with the increase of RE content. When the rare earth content is 1.5 %, the glass transition temperature reached maximum.(2) The rare earth complex [Dy2(L2)3(H2O)4]∞was synthesized by high temperature hydrothermal, in which L2 is citrazinic acid-based anionic ligands, and its crystal structure was analysed. The complex was doped with the PUA directly to prepare the rare earth complex/PUA composite material. The thermodynamic properties, fluorescent properties and internal structure of composite materials were characterized. The results reveal that the complex is dispersed in PUA at about 200500 nm. The material has the good thermal stability. Materiales were excitated by the excitation wavelength 469 nm light. In emission spectra, fluorescence intensity reached the maximum at the 515 nm. Fluorescence intensity grew with the increased content of rare earth complex. There was no fluorescence quenching phenomenon.(3) The rare earth complex {[Sm(L3)3(phen)]2(dmpy)(C2H5OH)2(H2O)2}∞with a reaction of a functional group (hydroxyl) can be synthesized by the vitro diffusion method, in which L3 is p-hydroxy acrylic acid-based anionic ligands and dmpy is 2,6-lutidine. The good fluorescence of the complex / PUA was obtained by chemical bond. Composite materials with the different content rare earth complex were investigated by light transmittance, thermal stability and fluorescence properties. Materials were excitated by the excitation wavelength 474 nm light. In emission spectra, fluorescence intensity reached the maximum at the 597 nm. In order to improve the material transmittance to do another set of comparative tests, DMF was introduced, which is "universal solvent". The complex first was dissolved in DMF, then bonding with PUA. The results showed that the transmittance of composite materials has further improved by using the DMF. What's more, DMF did not affect the fluorescence of materials, but the thermal property of materials has declined.(4) The rare earth complex {[Eu(H2L4)2(H2O)5](H4L4)}∞was synthesized using 5-amino-isophthalic acid as the ligand. The active functional group (–NH2) in the ternary complex was used to react with -NCO functional group of IPDI. By means of macromonomer technique, a novel photoluminescent material containing both the rare earth complex and PUA was obtained. The structure and properties of materials were characterized by FTIR, thermogravimetric analysis and fluorescence spectroscopy. Both the complex and photoluminescent polymer material emitted characteristic fluorescence at 616 nm after excitation at a wavelength of 349 nm. The fluorescent quenching wouldn't appear when the content of complex reached 8 %. Forthermore, the initial degradation temperature increased with increasing the content of complex.
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