Synthesis And Properties Of Conjugated Electroluminescent Materials

With the advantages of low driving voltage,high brightness,high efficiency,fast response and self-emissive,organic light-emitting diodes(OLEDs) show promise for applications as flat panel-displays and solid state lightning.Although rapid progress in some related products and technique has been made,two main problems,life and efficiency,still exist.In order to solve these problems design, synthesis and study of new OLEDs materials is necessary.Aimed at some good materials for OLEDs especially in red light-emitting,we've designed and synthesized a series of conjugated organic light-emitting materials.Primary luminescence properties of these compounds have been investigated.Firstly,we designed and synthesized several donor and accepter molecules which separately based on phenothiazine and 1,2,4-triazolo[1,5-a]pyrimidine.Also some modifications of these reactions have been done according to their mechanism.After that most of the target moleculars have been obtained with relatively high yield.Secondly,we synthesized some other compounds with D-π-A structures by the Wittig and Knoevenger reaction with the donor and the accepter molecules.The yields of these compounds ranged from modest to high.After characterization,photoluminescence and electoluminescence properties have been invested.All coupounds show strong UV-Vis absorption.The photoluminescence emittion wave length ranged from 470 run to 670 ran,and most of them are in the red light region.At last by the Yamamoto reaction we synthesized a polymer P1 with high thermal stabilities,large molecular weight and good solubility in high yield.The polymer was characterized by NMR,GPC,TGA,DSC.Trilayer LED was fabricated and the electro-luminescence properties have been investigated.With turn-on voltage of 6.0 V, pure orange light and the maximum efficiency 62 cd/m~2,the polymer show potential use as PLED materials.