【作者】 张海全；

【导师】 陈欣方； 马於光；

【作者基本信息】 吉林大学 ， 高分子化学与物理， 2004， 博士

【摘要】 当今是以信息为核心的知识经济时代，平板显示器作为人类获取信息的重要界面，其作用越来越显著。有机/聚合物电致发光器件作为平板显示器的重要一员，由于其独特的性能，备受科学界和产业界的重视。随着有机/聚合物电致发光器件工业化，推动了人们对有机/聚合物发光材料研究的深入。发光材料的研究已经从可见光发展到宽带隙的紫外光。目前，在宽禁带半导体研究中，无机宽禁带半导体材料已经取得了可喜的成绩，它们在可见光全色固体显示、高密度存储、紫外探测及在节能照明等方面开创了广阔的应用前景。与无机材料相比，宽带隙的有机/聚合物发光材料的研究相对滞后，因此发展宽带隙的有机/聚合物发光材料可能成为各国研究人员的一个新研究热点。 本论文设计、合成了一种可用于制备宽带隙发光材料的氧桥连七元内环联苯类单体，X 射线晶体学和分子力学模拟研究证明了它们具有唯一的空间构型，两苯环的扭曲角度为 40o。紫外吸收光谱数据表明了它们最大吸收峰介于平面分子芴和苯之间，苯环间 40o的扭曲并没有完全打断两苯环间的共轭，两苯环处于不完全共轭状态。 氧桥连的七元内环联苯类单体可用于共轭高分子改性，它与芴通过单键连接的交替共聚物 PDHFSCDH 显示了高效率的紫外发光，与相应的均聚芴 PDHF相比，带隙增大了 0.29 eV。氧桥连七元内环联苯单体与烷氧基取代的苯乙烯通 - i -<WP=105>中英文摘要 吉林大学博士学位论文过双键连接的交替共聚物 MEHSCD-PPV 也具有高的发光效率，与相应的MEH-PPV 相比，发射蓝移了 100nm。 氧桥连七元内环联苯类单体的均聚物 P1, P2 无论是光致发光还是电致发光最大发光峰位均在 372nm 左右, 显示了较强的紫外发射。模型化合物 D1 的 X射线晶体学和分子力学模拟研究显示了在聚合物 P1 或 P2 的主链上存在两种不0同的构象，即平面构象和扭曲构象，低能量的平面构象为发射的中心。在同一聚合物主链上，激子不能从高能量的扭曲片断迁移到低能量的平面片断，但是分子间这种迁移能够实现。聚合物 P1 或 P2 这种特征的宏观表现为；稀溶液时，发光强度强烈依赖于激发波长，固态时，发光强度对激发波长的依赖性明显减弱。模型化合物 D1 的 X 射线晶体学也表明了存在一种特殊的氢键，这种特殊的氢键及其构筑的网状结构是中心联苯平面构象的驱动力。本论文还合成、研究了与 P1 结构相似的扭曲聚合物 P3，它显示了与 P1 相同的空间结构特征和光物理性质。 本论文设计一种特殊结构的单体，由它构筑的聚合物、齐聚物是一类宽带隙有机/聚合物发光材料，以此为发光层制备了有机/聚合物电致发光器件。并首次在室温条件下观察到了紫外发射的有机/聚合物器件的电致发光，这为新型宽带隙发光材料及器件开发和应用研究提供了必要的依据。更多还原

【Abstract】 Up to date, Flat Panel Displays (FPDs) are playing important roles for mankindto get information and their effects are significant. Organic and polymerlight-emitting devices (OLEDs and PLEDs), the novel members of FPDs, haveattracted great attentions of the science fienld and industry for their excellentperformance. Industrialization of OLEDs and PLEDs drove the searching of new andgood-performanced organic and polymer light-emitting materials. The investigationof light-emitting materials already expand to ultraviolet light-emitting form visiblelight. Now, in the research of wide–bandgap semiconductor, inorganicsemiconducting materials had obtained outstanding success. They have wideapplication foreground in visible light solid display, high-density storage, ultravioletdetect and economy energy illuminance fields. Though the research onorganic/polymer luminescence materials with wide– bandgap is lag compared withinorganic materials, wide–bandgap organic /polymer materials will become theresearch focus in the world. In this paper, the monomers of seven-membered heterocycre bridged biphenylwere designed and synthesized and researched by X-ray crystallography andmolecular force field simulation, which proved that the monomers had only stablespace conformation and the twisted angle of the monomer is about 40o. Theabsorption data n indicated that maximal absorption peak is between planar fluorenemolecule’s absorption peak and benzene’s. The twisted angle of the two benzenesonly partly break the conjugation of biphenyl.The seven-membered heterocycre bridged biphenyl can be applied to modify theconjugated polymer. Alternating copolymer (PDHFSCDH) consisted of fluorene andseven-membered heterocycre bridged biphenyl showed high-efficient UVlight-emitting, and its bandgap increased 0.29 eV comparing with polyfuorene with - iii -<WP=107>中英文摘要 吉林大学博士学位论文C6 substituents at C-9(PDHF). Alternating copolymer (MEHSCD-PPV) composed ofseven-membered heterocycre bridged biphenyl and m-phenylene vinylene exhibitedhigh-efficient blue light-emitting, and its absoption and emission peaks blue shift100nm compared with MEH-PPV. The homopolymers (P1 and P2) parepared from the seven-memberedheterocycre bridged biphenyl monomer exhibited both UV photoluminescence andUV elctroluminescence. The X-ray crystallography and molecule model calculationinvestigation of model compound D1 of polymer ( P1) presences two differentconformation in one polymer chain (planar and twisted conformation). Here, planarbiphenyl conformation with low energy is the emitting center. The lesscommunication between two segments is likely corresponding to the effect ofemission spectra of solution strongly depended on the excitation energy. Theintrachain migration of the excitons may be limited by broken conjugation in PMPdue to the local twisting and meta-link sites in PMP chain. In the solid film, the lessdependence of the emission intensity on excitation wavelength indicates the presenceof direct interchain exciton energy transfer between two energy species. And theX-ray crystallography investigation of model compound D1 also exhibited apresence of peculiar hydrogen bonding, which is the driving force to form planarconformation. The twisted polymer P3 with similar structure was also studied. Itexhibited the same conformation character and photoluminescence property. Theresearch on electroluminescence devices indicated that itsEL emission is peaked at456nm. In this paper a series of monomers with novel structure were designed, and thepolymers and oligmers have wide-bandgap emission were synthesizedand thedevices based on them were invested . It is the first time that organic/polymer UVlight-emitting electroluminescence was observed at room temperature, which can be - iv -更多还原