以咔唑為主體之單體與共軛高分子之合成及其在PLED上的應用

Abstract

本論文利用Suzuki coupling的方法合成，聯苯上具有咔唑(carbazole)基團單體，同樣利用此偶合方法，與其他不同的單體進行共聚合形成高分子化合物P1~P5；此系列高分子化合物大致上有良好的熱穩定性( Td= 360~480 ℃)，經由光學性質、電化學性質的分析，可以瞭解不同主鏈基團對於高分子化合物性質的影響，並可以計算此系列高分子之HOMO-LUMO能階。

側鏈上咔唑(carbazole)基團的氧化二聚化，使得高分子化合物均有電聚合沉積的現象；二聚化咔唑(carbazole)之HOMO能階(~-5.2eV)接近ITO玻璃，因此將高分子化合物在ITO玻璃上電聚成膜，應用於電激發光元件，比較其不同電聚圈數、不同發光層之元件表現，發現P1、P3的電聚膜元件相對於標準元件(以PEDOT/PSS為電洞注入層)，在亮度與效率的方面都有大幅的提升，而其他高分子有降低啟動電壓的元件結果。

In this thesis, Suzuki coupling was used to synthesize biphenyl with carbazole group. The same method was also used to synthesize conjugated polymers P1~P5 with the other monomer. Those polymers we synthesized are almost with good thermal stability (Td= 360~480℃). From optical and electrochemical analyses, we find the properties of polymers were influenced by differential main-chain and we could calculate the HOMO & LUMO of polymers. The oxidative dimerization of carbazole group in the side-chain makes all polymers be able to electropolymerize. The HOMO level of the film of these polymers was about -5.2eV due to the dimerization of carbazole group which is close the femi-level of ITO. Therefore we application the electropolymerized film to Organic Light Emitting Diode device. Different amount of oxidative-reductive cycle and different materials of emitting layer made OLED devices with different performances. We find that the OLED devices consisted of the films of P1 and P3 formed by electopolymerization with better brightness and efficiency than standard device (using PEDOT/PSS as hole injection layer). The electopolymeriazed films of other polymers lower turn-on voltage of device.