具高螢光效率及紅移放光之三苯胺型聚醯亞胺分子設計與合成

Abstract

時至今日，設計一款具有高螢光效率且螢光光色紅移的全芳香族聚醯亞胺仍是一件非常具有挑戰的事情，其主要原因可以歸於電荷轉移配位物 (CTC) ，根據我們團隊過去的發表研究能夠知道，在聚醯亞胺的骨架中加入扭曲的結構可以很有效的保護螢光基團避免受到電荷轉移配位物的影響而淬滅，因此我們設計了一系列含有不同推拉電子效應或是或是包含聚集誘導發光性質取代基團的二醯亞胺及其衍生二酸酐，為了能闡明及調整這一系列二醯亞胺及其衍伸全芳香螢光聚醯亞胺的發光行為，在這篇論文中將透過螢光光譜及量子化學計算來解釋取代基團對聚醯亞胺發光性質的影響，這一系列的聚醯亞胺是透過將二醯亞胺合成的二酸酐配合二胺以一步聚合合成，其中TPE-4Me 展現出最高的光致螢光效率，高達42.7%而TPPA-4Me含有TPPA的結構展現出最紅移的螢光波長，紅移至 605 nm 但同時也展現出較低的螢光效率，而結合了TPPA及TPE結構的TPPA-TPE-4Me 展現出595 nm 的橘紅色螢光，儘管紅移效應不如 TPPA-4Me 中那麼明顯，但 TPE 的加入在固態下提供了更顯著的螢光行為。

Designing wholly aromatic polyimides (Ar-PIs) with high fluorescence quantum efficiency and red-shifted emission is still challenging due to the charge-transfer complex (CTC) effect. According to the previous study reported by our group, incorporating the twisted units into the polyimide backbone could effectively preserve the quantum efficiency of the luminophore. Therefore, in this thesis, we designed and synthesized a series of arylamine-based diimides and dianhydrides with various electron-donating or withdrawing pendant groups, including aggregation-induced emission luminogens (AIEgens), to tune and elucidate the emissive behaviors of the diimide compounds and their related Ar-PIs, respectively. In this thesis, the effect of various pendant groups on the luminescence of polyimides will be analyzed through fluorescence spectra and quantum chemical calculations. The fluorescence behavior is observed in polyimides synthesized through one-step polymerization of this series of dianhydrides with various diamines. In particular, TPE-4Me exhibits the highest quantum efficiency of 42.7%, while TPPA-4Me, which incorporates TPPA moieties, shows the most red-shifted emission at 605 nm but has a lower quantum efficiency. The combination of TPE and TPPA in TPPA-TPE-4Me results in orange-red fluorescence at 595 nm. Although the red-shift effect is not as pronounced as in TPPA-4Me, the addition of TPE provides more significant fluorescence behavior in the solid state.