Eu³⁺荧光共聚物及聚合物基复合材料的制备与性能研究

【作者】 许传杰；

【导师】 张明； 严长浩；

【作者基本信息】 扬州大学 ， 材料学， 2010， 硕士

【摘要】 稀土有机发光材料由于具有稀土离子独特的结构和性质,其发出的荧光兼有稀土离子发光强度高、颜色纯正和有机化合物所需激发能量低、荧光效率高、易溶于有机溶剂等优点,为人们探索新的发光能源、发光材料提供了新思路。本文的研究工作以合成新型的稀土高分子发光材料为中心,合成了具有聚合活性的稀土配合物及其共聚合反应的研究,以及对发光共聚物的性能的研究,探讨了影响发光聚合物材料发光性能的因素,并讨论了在聚合物基质中稀土离子间的共发光效应。论文主要从下面几个方面展开:一、具有聚合活性发光配合物的合成及其性能研究以氧化铕为原料,α-甲基丙烯酸为第一配体,1,10-菲啰啉为第二配体，以水为溶剂,采用共沉淀的方法制备了铕发光配合物Eu（MAA）3phen,为合成键合型稀土高分子材料提供了原料,并对其组成、结构和性能进行了表征。研究结果表明配合物为双齿配位结构;元素分析表明配合物的化学组成为Eu（MAA）3phen; XRD分析表明配合物具有良好的结晶性能,单晶解析结果进一步确定了配合物的结果为双齿配位结构;紫外吸收光谱表明第二配体phen在紫外区域具有强烈的吸收,且配合物在紫外区的能量吸收主要表现为配体phen的π-π*跃迁吸收;STA测试结果表明配合物具有良好的热稳定性能,1,10-菲啰啉的引入使得配合物的热稳定性能稍有下降;配合物在紫外光激发下能发射出Eu3+的特征红光,而且配合物的荧光强度随着稀土离子浓度的增大和温度的升高均出现了不同程度的荧光猝灭现象。二、研究了配合物在合成稀土高聚物荧光材料中的应用稀土高分子材料既具有稀土离子独特的光、电、磁等特性,又具有高分子材料质量轻、抗冲击力强和易加工成型等优良性能,是极有潜在应用价值的功能材料。本文选用了自制的具有高荧光性能和聚合活性的含铕配合物（Eu（MAA）3phen）、苯乙烯（St）、甲基丙烯酸甲酯（MMA）作为单体,采用自由基本体共聚合的方法,通过浇注成型制备了具有发光功能的透明光学高分子共聚物材料,对其相关物理、化学性能进行了研究,考察了配合物的加入对高分子基材相关性能的影响,并探讨了对发光共聚物发光性能的影响因素。结果表明稀土配合物Eu（MAA）3phen复合到聚合物中后,仍能发射出强烈的稀土离子的特征荧光,并且共聚物的韧性得到一定程度的提高。所有含稀土配合物荧光高分子材料具有很好的透明性,其可见光透过率在90-95%之间,PS对配合物中有机配体的紫外光区能量吸收没有影响,可以作为与配合物Eu（MAA）3phen复合的基质材料。在所研究的范围内,光学材料的荧光发射强度随着配合物掺杂浓度的增加而增强并没有出现“荧光猝灭”现象。三、研究了异种稀土离子的荧光增强效应和发光稀土离子的共发光效应稀土发光离子不但可以从配体中吸收能量使其发光效率提高,而且可以通过不同稀土离子间的能量传递,能量转移使得荧光增强。而且对稀土有机高分子,不同稀土掺杂材料以及稀土离子共存对材料荧光性能的影响研究还很少见。本文分别用不发光的稀土离子Gd³⁺、Pr³⁺、Nd³⁺和发光性能较差的稀土离子Dy³⁺、Sm³⁺制得MAA、phen的三元配合物,然后将制得的配合物分别和含铕的稀土配合物共掺杂于聚苯乙烯基质中,制备了共掺杂型稀土发光聚合物。讨论了稀土离子的掺杂对含铕聚合物荧光性能的影响。荧光测试结果表明异种稀土离子与发光中心Eu³⁺的半径接近才能对其发光强度起到增强作用,其中Gd³⁺、Sm³⁺与Eu³⁺之间有明显的敏化作用,并且Gd³⁺对Eu³⁺的敏化作用好于Sm³⁺;Dy³⁺、Pr³⁺、Nd³⁺在共聚物中对Eu³⁺起到猝灭作用。本文还研究了掺杂发光稀土中心离子的共发光效应,选用发射强荧光的Tb³⁺和Eu³⁺中心离子配合物,通过不同的掺杂方法将配合物Eu（MAA）3phen、配合物Tb（MAA）3phen和PS共掺杂制得了掺杂型稀土高分子荧光材料。研究了对聚合物荧光性能的影响因素以及在不同的掺杂方法下Tb³⁺与Eu³⁺在聚合物中的相互作用。荧光测试结果表明聚合物中配合物的质量分数会影响到荧光材料的敏化程度,并且通过键合法制得的共发光材料的敏化程度最大。本文的研究结果表明,经典自由基聚合的各种实施方法合成的键合型稀土高分子材料,既具有基材的特征,同时由于稀土离子的引入,材料被赋予了新的功能,具有良好的应用前景。更多还原

【Abstract】 Rare earth polymers luminescence material have become excellent luminescence materials, this is due to lanthanide ions,speculiar characteristics. Advantages such as high strength, color pure fluorescence because unique structure and nature of rare earth ions, and low exciting energy, high fluorescence efficiency, soluble in organic solvents the same as organic compounds can be found in rare earth luminescent organic materials. So a new way was provided to people to explore new light energy and new light-emitting materials.In this paper, the research was focus on synthesis of new rare-earth luminescent polymer, got down to work by synthesis of rare earth complexes with polymerization activity, studied synthesis the luminescent copolymers and their copolymerization and the impact factors of their luminance, and discussed the co-luminance between rare earth ions in polymer matrix. Reaching work was started from the following aspects:1. Synthesis the luminescent complexes with polymerization activity and studying their propertiesEu（MAA）3phen luminescent complexes were prepared by co-precipitation method in this paper. Europium oxide was used as raw material,α-methyl acrylic acid as the first ligand and 1, 10-phenanthroline （phen） as the second ligand. The complexes can be used in the synthesis of bonding type rare earth polymer. The composition, structure and properties of the complexes were characterized in this paper. Element analysis showed that the composition of complex is Eu（MAA）3phen. XRD analysis showed the good crystalline properties of the complexs. The single crystal analytical shows the ligands bi-coordinated with the RE ions in the complexes. UV absorption spectra showed the characteristic absorption peak of phen. The result shows the mainly energy absorption peak was theπ-π* transition peak of phen in ultraviolet region. STA analysis shows the good thermal stability of the complexes. The thermal stability of the complexes were a little decreased as the additional phen ligand. The complexes show the characterize emission peak of Eu³⁺ ion. The different degrees of self fluorescence quenching were found with increasing the rare earth ion concentration and temperatures.2. Studied of the applications of rare earth complexes in the synthesis of fluorescent polymerRare earth polymer not only has the unique properties of rare earth ions such as optical, electrical, and magnetic and so on, but also has the properties of the polymer materials such as light weight, shock resistance and easy processing of molding and other fine performance. So it can be used in the synthesis of functional materials with potential application. Luminescent and diverge transmitted light optical copolymer materials were prepared by casting molding process. The prepared complexes （Eu（MAA）3phen） were used in free radical co-polymerized with styrene （St）, methyl methacrylate （MMA） as monomer showed the high fluorescence properties and polymerization activity. The relevant physical and chemical properties of the co-polymer were studied. The influences on the related performance of polymer by the addition of the complex were investigated. The affection on the light emitting performance of the copolymer was discussed. The results showed that the strong characteristic fluorescence emission of rare earth ions was showed in the co-polymer after the rare earth complex （Eu（MAA）3phen） copolymerized with St or MMA. The toughness of the copolymer was increased. All fluorescent materials with rare earth complexes have good transparency; its visible light transmittance was 90-95%. The copolymerization took no affection on the UV region of energy absorption of the organic ligands in complexes, so it can be used as the composite raw material in the synthesis of Eu（MAA）3phen complex. In this paper, the intensity of fluorescence of rare earth material did not occur "fluorescence quenching"phenomenon, with the increase of its doping concentration increase.3. Studied of the luminescence enhancement with the heterogeneity rare earth ions and co-luminescence effect of rare earth ionsThe luminescent rare earth ions can absorb energy from the ligand to enhance the luminescent efficiency, many different rare earth ions are also can be energy transfer, and fluorescence energy transfer can enhance the luminescent intensity of the luminescence material. On the rare earth organic polymer, different rare earth ions hybrid materials still has good fluorescence properties is rare reported. In this paper, rare earth ion Sm³⁺, Pr³⁺, Nd³⁺ and no luminescence performance of rare earth ions Dy³⁺, Sm³⁺ complexes were synthesized with MAA, phen were used as ligand. The obtained complexes were doped with europium rare earth complexes in the polystyrene matrix respectively. The co-hybrid doped luminescent rare earth polymer was prepared. The rare earth ions doped polymer containing fluorescent properties of Eu were discussed. The results show that the heterogeneous fluorescence and luminescence of rare earth ion radius close to the central ion can enhanced role of the luminescent intensity, in which Gd³⁺, Sm³⁺ and Eu³⁺ between the apparent sensitization, and Sm³⁺; Dy³⁺ on the sensitization of Eu³⁺ is better than Sm³⁺; Dy³⁺, Pr³⁺,Nd³⁺on Eu³⁺ in the copolymer play a role in quenching.In this paper the co-luminescent effect of doped central luminescent rare earth ion was studied, doped fluorescent polymers were prepared by using strong fluorescence complexes with Tb³⁺ and Eu³⁺ as central ion. The fluorescence properties effect factors of polymers and the interaction between Tb³⁺ and Eu³⁺in the polymers under different doping methods were studied. Doped rare earth polymer materials were obtained by different doping method, with Eu（MAA）3phen,Tb（MAA）3phen and PS,the fluorescent test results show that the complex concentration in the polymer will affect the degree of sensitization of the fluorescent materials, and sensitizing effect of the luminescent ions was increased by changing doping methods.The results showed that rare earth bonded polymer materials synthesized by various implementation methods of the classical free radical polymerization, had been given both the characteristics of the base material and new functions because the introduction of rare earth ions, so it had a good application prospect.更多还原