高分子發光二極體(PLED)的發光乃是藉由從陰極與陽極分別注入電子與電洞，並於發光層再結合形成放光現象，因此電子與電洞注入和傳遞的平衡是影響元件效率的重要因素。但是在大部分的有機共軛材料中電洞的傳遞速率比電子快，常常無法使載子有效地在元件發光層再結合，因此大幅降低其電流效率，故本研究合成出可以幫助電子傳遞的電子傳輸材料。
本研究利用Suzuki coupling reaction聚合出主鏈含1,3,4-噁二唑衍生物以及側鏈具有可提升溶解性的長碳鏈醚基的高分子P1作為電子傳輸材料，以核磁共振光譜(1H-NMR)及元素分析儀(EA)鑑定其結構，並且探討高分子P1之熱性質、光學性質以及電化學性質。
P1的熱裂解溫度(Td)為305.5 oC，玻璃轉移溫度(Tg)為96.2 oC顯示具有高熱穩定性。薄膜態UV-Vis有兩個明顯吸收峰，分別在323 nm與383 nm，由起始吸收波長(UVonset)推算出高分子能帶間隙(Egopt)為2.84 eV；螢光光譜(PL)放光波長在442 nm。由循環伏安法(Cyclic Voltammetry)量測計算出P1的LUMO能階(-2.73 eV)與HOMO能階(-5.64 eV)，電化學法的能階差(Egel)為2.91 eV，且由其低HOMO能階顯示P1具有電洞阻擋的特性。

In this work, we synthesized a polymer (P1) containing oxadiazole groups to be an electron-transport material. P1 was synthesized successfully by Suzuki coupling reaction, and chemical structure of P1 was characterized by 1H-NMR and element analysis. Also, the physical properties (thermal, optical, electrochemical) were investigated from DSC, TGA, optical spectra and cyclic voltammetry respectively. The decomposition temperature (Td) and glass transition temperature (Tg) of P1 are 305.5 oC and 96.2 oC respectively which reveal P1 good thermal stability. In film state, the absorption and photo luminescence peaks of P1 are at 323/383 nm and 442 nm respectively. The HOMO and LUMO levels of P1 are -5.64 eV and -2.73 eV respectively. The LUMO level of P1 (-2.73 eV) is closed to emitting layer HY-PPV (-2.8 eV), meaning P1 should efficiently help electron transporting. The HOMO level of P1 (-5.64 eV) is much lower than HY-PPV (-5.0 eV), meaning P1 exhibits good hole-blocking ability.

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