光電高分子材料於有機發光二極體之應用與製備多面體聚矽氧烷/單壁奈米碳管之奈米複合材料

Abstract

高分子間作用力是探討材料應用性的關鍵。本論文可分成兩個部分,第一個部分 主要研究不同交聯方式的高分子,其不同的作用力在有機發光二極體中的應用;第二個 部分是研究利用兩種不同超分子作用力來製備多維度之奈米複合材料。 第一個部分可分為兩個題目,分別是:光交聯型共軛高分子應用於有機發光二極體; 以及可交聯型三苯氨衍生物應用於有機發光二極體。光交聯型共軛高分子為高分子側鏈 帶有尿嘧啶官能基(PTC-U),利用尿嘧啶官能基可進行 2 + 2 光交聯反應,形成化學交 聯型態的共軛高分子,以提高其抗溶劑腐蝕性質,同時提高了電洞的移動速率。元件效 率測試得到 PTC-U-1hr 的效率(Qmax = 9.68% and LEmax = 36.6 cd/A),是市售品 PEDOT:PSS 的 2.2 倍(Qmax = 4.29% and LEmax = 16.2 cd/A),證明化學交聯共軛高分子可 大幅提高有機發光二極體的效能。交聯型三苯氨衍生物為,三苯氨帶有氧代氮代苯并環 己烷官能基(TPABZ),TPABZ 具有好的熱穩定性質且無需催化劑就可進行熱開環交聯反 應形成高分子 P-TPABZ,其電子能階也相當適合應用於有機發光二極體中的電洞注入 傳輸層;進一步探討其小分子(TPABZ)與熱交聯聚合之高分子(P-TPABZ)的元件效率比 較,可以發現 P-TPABZ 作為電洞注入傳輸層材料可以得到相當不錯的元件效率(EQE: 2.44%; LEmax: 8.42 cd/A; PEmax: 4.34 lm/W)。 第二個部分利用兩種不同之超分子作用力製備聚氧代氮代苯并環己烷/多面體聚矽 氧烷/單壁奈米碳管之三項混摻奈米複合材料,首先利用合成設計氧代氮代苯并環己烷 (Py-Bz-T),兩端帶有不同超分子作用力官能基,分別是芘(Pyrene)與 DNA 鹼基對的胸腺 嘧啶(T); Py-Bz-T 可和帶有 DNA 鹼基對的腺嘌呤(A)的 OBA-POSS,進行 A···T 超分 子作用力的分子識別形成 Py-Bz-T/OBA-POSS 奈米複合材料;之後,利用 pyrene 可以 和單壁奈米碳管進行 – 堆積作用力的物理貼合,得到三項混摻之奈米複合材料,並利 用穿透式電子顯微鏡與螢光光譜探討其分散奈米碳管情形。

The interaction between polymer chains is important to apply in various fields. In this study, we investigated the different cross-linking process for application of polymer optoelectronic materials as hole injection/transporting layer materials in Organic light-emitting diodes (OLED) in the frist part (chapter 1, 3, and 4). In the second part (chapter 2 and 5) we investigated a hybrid nanomaterials with multidimensional structures through supramolecular interactions. In the first part, we used a new process for modifying a polymeric material for using as hole injection transport layer in organic light-emitting diodes has been studied, which is through 2 + 2 photodimerization of a DNA-mimetic -conjugated poly(triphenylamine-carbazole) presenting pendent uracil groups (PTC-U) under 1 h of UV irradiation. Multilayer phosphorescence OLED device with the PTC-U-1hr as a hole injection/transport layer is fabricated by successive spin-coating processes, and a remarkable improvement in performance (Qmax = 9.68%, Bmax = 41,466 cd/m2, and LEmax = 36.6 cd/A) relative to the commercial product (poly(3,4-ethylenedioxy-thiophene): polystyrenesulfonate) PEDOT:PSS (Qmax = 4.29%, Bmax = 15,678 cd/m2, and LEmax = 16.2 cd/A) has been achieved. We also have synthesized TPABZ, a new thermally cross-linkable triphenylamine derivative containing a benzoxazine functional group, for application in OLEDs. TPABZ is readily polymerized through ring-opening polymerization of its benzoxazine unit, upon heating at 220 oC for 30 min. The cured TPABZ (P-TPABZ) is suitable for use as a hole injection/transport material in OLEDs, and we fabricated multilayered OLEDs (ITO/TPABZ or P-TPABZ/NPB/Alq3/LiF/Al); the device incorporating P-TPABZ exhibited good performance (EQE: 2.44%; LEmax: 8.42 cd A−1; PEmax: 4.34 lm W−1). In the second part, we investigated ternary polybenzoxazine/POSS/SWCNT hybrid nanocomposites stabilized through supramolecular interactions. We linked zero-dimensional POSS with one-dimensional SWCNTs as dual-dimensional nanohybrid complexes within polybenzoxazine matrices, stabilized through noncovalent supramolecular interactions. First, we synthesized a new bifunctionalized benzoxazine (Py-Bz-T), presenting thymine (T) and pyrene (Py) units, that displayed excellent thermal properties after thermal curing, because its T moieties increased the physical cross-linking density. Second, we prepared Py-Bz-T/OBA-POSS nanocomposites and investigated the multiple hydrogen bonding A···T interactions between Py-Bz-T and OBA-POSS. Finally, we prepared Py-Bz-T/OBA-POSS/SWCNT ternary hybrid complexes dispersed in THF, stabilized through both multiple hydrogen bonding and – stacking interactions.