Development of Amorphous Electron-Transport Material for Organic Electroluminescent Devices

采用有机铜化学方法，通过溴代反应和交叉偶联反应合成了两种全氟苯树枝状大分子C_<60>F_<42>（MW = 1518）和C_<132>F_<90>（MW = 3295）。另外<60><42>还制备了两种含对三联苯和对四联苯的C_ F_2异构体，考察了它们的结构与性质的关系。三种C_<60>F_<42>s的玻璃化转变温度为125-135℃。树枝状聚合物C_<132>F_<90>在426℃熔融，没有玻璃化转变。采用高真空热蒸发法，以TPTE（一种三苯胺的四聚体）为空穴传输层，三（8-羟基喹啉）铝为发光层，全氟代苯为电子传输层，LiF和铝为发光层，在铟锡氧化物玻璃衬底上制备了有机电致发光器件。在24.4V时，器件的最大亮度为2860 cd/m^2。电化学测试表明，器件的性能随着电子亲合势的增加而提高 ...更多信息 化合物。这可能是因为电子亲合势的增加降低了金属层和电子传输层之间的电子注入势垒。采用有机铜交叉偶联法合成了全氟对苯齐聚物（PF-5 P ~ PF-8 P）。还制备了两种含三氟甲基和全氟-2-萘基的PF-6P衍生物。所有化合物均为无色固体，不溶于普通有机溶剂。差示扫描量热法测量表明，它们是高度结晶的固体，没有玻璃化转变。与全氟亚苯基树枝状聚合物相比，全氟低聚对亚苯基的电子传输性能优异。PF-7 P和PF-8 P的亮度-电压和电流-电压特性与PF-6P基本相同，推测PF-6P和PF-8 P的电流密度是由层内电子迁移率而不是界面电子注入决定的.少

Two perfluorinated phenylene dendrimers, C_<60>F_<42> (MW = 1518) and C_<132>F_<90> (MW = 3295), have been synthesized via a sequence of brominations and cross-couplings using organocopper chemistry. Two other C_<60>F_<42> isomers containing p-terphenyl and p-quaterphenyl groups were also prepared to see structure-property relationships. Three C_<60>F_<42>s showed glass transitions at 125-135℃. Dendrimer C_<132>F_<90> melts at 426℃ and did not show a glass transition. Organic light-emitting diodes have been fabricated on indium-tin-oxide coated glass substrates by high-vacuum thermal evaporation of TPTE (a tetramer of triphenylamine) as the hole-transport layer, tris (8-quinolinolato) aluminum as the emission layer, perfluorinated phenylenes as the electron-transport layer, LiF, and Aluminum. The maximum luminance of the device is 2860 cd/m^2 at 24.4.V.The electrochemical measurements indicated that the performance of the devices is improved with increasing electron affinities of The c … More ompounds. This is probably because the electron-injection barriers between the metal layers and the electron-transport layers are reduced by increased electron affinities.Perfluorinated oligo(p-phenylene)s including perfluoro-p-quinquephenyl to -octiphenyl (PF-5P to -8P) have been synthesized by the organocopper cross-coupling method. Two PF-6P derivatives containing trifluoromethyl and perfluoro-2-naphtyl groups were also prepared. All compounds are colorless solids and insoluble in common organic solvents. The differential scanning calorimetry measurements indicated that they are highly crystalline solids without glass transitions. The electron-transport capabilities of perfluorinated oligo(p-phenylene)s are excellent compared with perfluorinated phenylene dendrimers. The maximum luminance of the naphtyl derivative is 19970 cd/m^2 at 10.0 V.The luminance-voltage and current-voltage characteristics of PF-7P and -8P are almost identical to those of PF-6P.We speculate that the electron mobility in the layer rather than the electron injection at the interface is responsible for determining the current density of PF-6P to -8P. Less