Synthesis and Characterization of Novel Light Emitting Materials Containing Thiophene Units and Methoxy Side Groups
Dr. Lin, Hong-Cheu
|摘要:||本研究在於合成及探討含口塞吩環與側邊氧甲烷基之三環共軛的螢光材料。此類化合物是以anil reaction合成的及其類似的聚合物以Wittig Reaction合成，由共軛及非共軛的柔軟基兩部分構成; 含口塞吩環與側邊氧甲烷基之三環共軛的寡聚物模型分子(Oligomer model compounds)與其衍生的高分子作一特性的比較。藉由改變在分子長軸末端的取代基來作結構上的修飾，並利用熱微差掃描卡計(DSC)和偏光顯微鏡(POM)做其相關液晶行為的量測，發現到小分子的S-OC8與S-OC12有Nematic的液晶相存在，範圍約10~15℃左右；而oligomers都沒有液晶相存在，其為amorphous oligomers。而化合物的光學及電學性質則由紫外光/可見光光譜儀、螢光光譜儀及電致發光光譜儀量測; 共軛有機分子末端長碳鍊的改變，對螢光體而言並沒有太大的影響。在元件方面，其結構為ITO / PVK:oligomers(100:1)/Ca/Al，驅動電壓大約在23V左右。|
This report is to synthesize and investigate novel photoluminent materials containing thiophene in the chromophore units and methoxy side groups. These compounds and analogous polymers containing conjugated and flexible parts are synthesized by Witting reaction and anil reaction. These model compounds having three conjugated-rings are compared with the derivative oligomers. These oligomers are souble in common organic solvents and thermally stable on heating(the weight loss was less than 5% on heating to about 278.42~365.00℃ under nitrogen atmosphere). By modification of the side chains and end groups of the conjugated molecules, we are able to characterize their mesogenic behavior by DSC and POM. We find S-OC8 and S-OC12 of these model compounds have liquid crystalline phase. Which phase is Nematic phase. The optical and electric properties of the compounds are determined by UV-vis, photoluminescent (PL) and electroluminescent (EL). These measurements reveal that the tuning of end groups would not affect their fluorescence properties significantly. The turn-on voltage of P-SC8、P-SC12 and P-SEO3 are about 23V, respectively, when the single-layer light-emitting diodes of ITO glass/PVK:oligomers(100:1)/Ca/Al were fabricated.
|Appears in Collections:||Thesis|