高相对分子质量8-羟基喹啉锂聚合物的制备和性能

高分子电致发光显示器(PLED)是近几年来国际、国内的研究热点,取得了很大的进展,其中高分子化金属配合物是一类很有价值的功能材料。通过甲基丙烯酸甲酯(MMA)、苯乙烯(S)和含有8-羟基喹啉的单体共聚合成模板聚合物,再与氢氧化锂作用,实现了8-羟基喹啉锂配合物的高分子化,获得了一种能够溶解在普通的溶剂中的高相对分子质量的含喹啉锂配合物的发光聚合物,并利用元素分析、¹H-NMR、FTIR、UV、PL光谱、DSC、TGA、GPC等方法对其结构和性能作了表征。紫外吸收和光致发光(PL)光谱说明合成共聚物的发光来自于Liq基团,引入的可聚合的链段以及共聚物中的甲基丙烯酸甲酯或苯乙烯链段,并没有影响发光波长的改变。亲核溶剂改变8-羟基喹啉金属配合物分子结构,使共聚物光谱明显红移20nm左右。

Synthesis and Characterization of High Molecular Weight Polymers Containing 8-Hydroxyquinoline Lithium Complexes

The electroluminescent polymer-metal complexes constitute an important class of functional materials and have found widespread use in the polymer light-emitting diodes(PLED). In recent years, they have become a new and fascinating area of research and attracted great interest as future flat-panel displays in the global and obtained the prodigious progress. As we known, there are two traditional approaches to obtain electroluminesent metalloquinolate thin films: vapor deposition in vacuum from the small molecules and filmcasting from the solution of the metalloquinolate-doped polymers. However, morphological changes during thermal treatments lead to partial crystallization of layered structure that ultimately results in device failure. Although the metalloquinolate-doped polymers can overcome these problems, current limitations are their heterostructures, which will affect device efficiencies and lifetimes. The metalloquinolate-contianing polymers that the covalent bond formatted between 8-hydroxyquinoline metal complexes with polymers for electroluminescence applications in PLEDshould combine the fluorescent properties of metalloquinolate and the processability of polymer. Anew method to synthesize 8-hydroxyquinoline lithium (Liq)-containing polymers were reported. Aseries of model polymers containing 8-hydroxyquinoline ligands were obtained by free-radical copolymerization with methyl methacrylate (MMA), styrene(S). High molecular weight polymer-lithium complexes were simply prepared by coordinating reaction of model polymers with lithium hydroxide. It is linear without cross-linking and can be dissolved easily in the common solvents, such as tetrahydrofuran(THF), and N,N′-dimethyl formamide(DMF). The method is fit to synthesize most of 8-hydroxyquinoline metal chelates-containing polymers by change the polymer chains or metal central ion. Their structures and performances were confirmed by NMR, FTIR, ultraviolet-visible absorption, photoluminescence spectrum, DSC, TGAand gel permeation chromatography analysis. Ultraviolet-visible absorption and PL emission spectra are consistent with that of small molecular weight Liq complexes that show the luminescence of polymers is nothing to do with polymer segments, but due to containing Liq functional group. The solvents, such as THF, affected the conjugated electrons in quinolinolate group and made the spectra of polymers a red shift obviously.