交聯型電洞、電子傳導層和 聚芴高分子的合成及其在 高分子發光元件上的應用

Abstract

本研究成功合成出帶有oxetane官能基的oxadiazole (Oxa-oxe)和 triazole (Tri-oxe) 電子傳導分子、 triphenylamine (Tpa-Oxe) 電洞傳導分子及polyfluorene (P2)發光層材料，並且用H1-NMR, C13-NMR, IR, Mass 和 EA等儀器鑑定合成的結果。從Dsc圖譜得知，在Polyfluorene側鏈位置導入oxetane破壞了原本的結晶性，交聯過後P2的 Tg 比未交聯者高了十度。從交聯後溶解度測試得知，只有P2和Tpa-Oxe的薄膜可以交聯，而Oxa-Oxe,和Tri-Oxe電子傳導分子則無法交聯。根據CV量測所得的能階圖得知，Tpa-Oxe是一個好的電洞注入材料; Tri-Oxe 為一個好的擋電洞材料而Oxe-Oxe除了是一個好的電子注入材料同時也是一個好的擋電洞材料。初步測試，本實驗所製作的元件亮度介在58~330 Cd/m2之間而效率值介在0.05~2.69 Cd/A之間。利用將發光層交聯的方式作為元件，可以增加載子注入在發光層之後的穩定性，得到較多的激子及較高的光通量。從EL的圖譜得知，利用交聯過後的P2為發光材料，可以避免高分子鏈之間靠得太近而產生g 帶，即可得到較純的光色。

In this research work, we have successfully synthesized the carrier-transporting materials containing the oxetane crosslinkable groups such as oxdiazole (Oxa-oxe), triazole (Tri-oxe) and triphenylamine (Tpa-oxe), and polyfluorene light emitting material containing the oxetane crosslinkable group (P2). From DSC results, we can clearly observe that the crystallinity of polyfluorene was reduced by incorporating the oxetane group into the side chain of polyfluorene, and the Tg of the Polyfluorene was increased from 25℃ to 35℃ after crosslinking. We also found that only the films of Tpa-Oxe and P2 can be crosslinked with the initiator of triarylsulfonium hexafluorophosphate, but the films of Tri-Oxe and Oxa-Oxe can’t. Based on the CV results, the hole injection properties of Tpa-Oxe materials was not significantly changed after crosslinking. Preliminary results also showed that the brightness of all the fabricated PLED devices was in a range of 58~330 Cd/m2 with the efficiency of 0.05~2.69 Cd/A. Due to the fact that Crosslinking can prevent the adjacent chain segments from quenching with each other and restrain the existence of the g band, it increase the number of excitons in P2 to emit light.