Study On The Synthesis Of Organic Conjugate Polymer Containing Carbazole Ring

In 1987, C. W. Tang et. al. firstly fabricated the organic electro luminescence devices (OELD), where aromatic diamine derivatives were used as hole transfer materials and tris(8-hydroxy-quinoline)aluminum(IHXAlq3) as luminescence layer. It is affirmed that the OELD with high efficiency and high brightness can be achieved by using new organic membrane materials for the first time, which inspires further studies on organic electro luminescence (OEL) phenomena. OEL materials have many advantages such as high brightness, high efficiency, wide visual view, fast response, rich color, low cost and so on. Besides, they also can be driven by direct current of low voltage, processed into various shapes owing to the excellent mechanical properties, or made into large displays of full color. In this promising field, therefore, many chemists are devoting themselves to investigating the synthesis techniques and photophysical behaviors of new and excellent electro-luminescent materials.Carbazole is characteristic of its excellent hole-transporting ability, which definitely hinder the crystallization process and thus prolong their lifetime values, and meanwhile increase the opportunities of electron-hole complexion to get high enough luminescence efficiency. While 1,3,4-oxadiazole is a typical electron-transporting group, and its copolymerization with carbazole makes it possible to get an excellent equilibrium between holes and electron carriers. Additionally, the 1,3,4-oxadiazole rings can decrease the electron cloud density of double bonds cloud and effectively prevents their oxidization, which stabilizes and optimizes the final devices. Molecular modification of carbazole by different alkyls increases the solubility in common organic solvents, and conduces to form thin film.Based on the relevant literatures, herein three series of OEL materials are synthesized according to the Wittig reaction: (1) conjugate copolymer containing carbazole ring and benzene ring; (2) conjugate copolymer containing carbazole ring and polyalkene; (3) conjugate copolymer containing both carbazole and 1,3,4-oxadiazole ring. Subsequently, the structural characterization is carried out using various analytical techniques.