以三伸苯為核心之星狀化合物及新型三苯胺聚合物的合成與性質研究及其在有機光電元件的應用

Abstract

在現今蓬勃發展的有機半導體材料及元件中，電荷產生、注入、傳導與再結合等性質方面的研究，一直引起人們廣泛的注意。近年來有機電激發光元件在學術研究上扮演著重要的角色，本篇論文的主旨是要合成出有機電激發光元件中的電洞傳輸材料。分子的設計是選用盤狀液晶的多苯環核心，主要是由於其具有良好的π-π堆疊及多電子的性質，具有電洞傳輸的特性。此外，為了使有機分子能夠形成電聚薄膜，我們選用在低氧化電位就能產生電聚合反應的三苯胺基團及咔唑基團當作末端基，而三苯胺基團及咔唑基團具有高電洞傳導特性，也是常用的有機電洞傳導物質。 因此我們合成出以三伸苯為核心，以碳鏈當作連接基團，接上數個不同的三苯胺基團或咔唑基團之星狀化合物，佐以循環伏安法觀察此一系列化合物之電化學行為，探討不同三苯胺基團或咔唑基團對於此類分子之電聚效果的影響，並將其運用在有機電激發光材料上，皆有不錯的效果。 另外，在合成此系列化合物的過程中，我們意外發現一個由三苯胺衍生物進行自縮合反應所得到的新型三苯胺聚合物，此化合物運用在PLED的電洞修飾層上有良好的電洞注入及傳導性質。

The studies of charge injection, transport, recombination, and light emission process in organic semiconductor materials have drown a lot attention. In this paper, we planed to synthesize the hole-transfer material in organic light emitting diode (OLED). Because of owning the property of π-π stacking and electron-rich, we employ the aromatic ring which usually used as the cores of discotic liquid crystals. We choose the triphenylamine and carbazole derivatives as the end group, which would electropolymerize in low oxidation electric potential to form hole-transport film. We synthesize a series of star-burst compounds using triphenylene as the core, alkyl chain as the linker to connect the core with the triphenylamine / carbazole derivatives. The electrochemical properties of those star-burst compounds were studied by cyclic voltammetry. Then we fabricate OLED device by employing those electropolymeric film as the hole-transport layer, and all the devices show well-performance. We develop a new triphenylamine-based hyperbranched oligomer which synthesized through self-condensation of 4-(4-(diphenylamino)- benzyloxy)butyl 4-methylbenzenesulfonate. The hyperbranched oligomer could electropolymerized, and the electropolymeric film as the modification layer in OLED device shows good hole-transport and injection properties.