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1.
主链含电子传输型基团的可溶性PPV发光特性研究   总被引:5,自引:0,他引:5  
经由Witig-Horner反应合成了一种可溶的PPV主链含有电子传输基团的新型结构电子聚合物。该低聚物的Mw=1000、Td=270℃,可溶于氯仿和四氢呋喃。构造了最简单的三明治式电致发光器件ITO/O-PPV(80nm)/Al,其电致发光和光致发光光谱基本一致。该器件与同样结构的PPV相比其EL表现出在509nm处单一的宽峰,而PPV的器件为520nm和550nm的双峰。另外由于主链上含有电子传输特性的二唑基团及聚合物材料的分子量较小,器件的量子效率达到0.13%,是同样结构器件PPV量子效率的五倍  相似文献   

2.
运用量子化学从头算ab initio HF方法对聚对苯撑乙烯剂聚物及其衍生物的几何结构进行了优化,分析了前线分子轨道成分,确认了电子光谱的跃迁轨道。计算结果表明,聚苯撑乙烯剂聚物及衍生物的电子云分布与其结构密切相关,不同取代基修饰下的二聚苯撑乙烯的电子光谱发生红移,且随取代基推电子能力加强红移显。电子光谱跃迁主要是最高占据轨道向最低空轨道之间的π-π^*跃迁,计算结果和实验吻合得很好。  相似文献   

3.
通过共聚合将噁二唑结构单元引入苯乙炔(PPV)主链,以改进电子注入与传输性能;用离子传导型的聚氧乙烯(PEO)链作为高分子的侧链.用该种聚合物制作的发光二极管(LED)与不含噁二唑的同类结构的共轭聚合物相比,性能明显提高,并制作了发光电池(LEC),对其性能进行初步研究.  相似文献   

4.
朱路  马晓梅  郑震  唐小真 《应用化学》2004,21(11):1155-1159
含有离子传输单元的聚对苯亚乙烯聚氧化乙烯多嵌段聚合物致发光材料的合成;嵌段共聚;发光电化学池  相似文献   

5.
有机电致发光特性;含TPD结构单元电荷传输聚合物的合成及其在EL器件中的应用  相似文献   

6.
采用密度泛函理论(DFT)的B3LYP/6-31G(d)方法对以低聚噻吩为端基、 苯并二噻吩(TPT)和并三噻吩(TTT)为共轭桥、 炔键为连接臂的20个模型化合物进行了计算研究. 在优化中性与离子态几何构型基础上, 获得了前线轨道能级、 电离能(IPs)、 电子亲和势(EAs)、 空穴/电子重组能(λhe)、 载流子迁移率(μhe)及吸收光谱等信息. 结果表明, 炔键的引入及端基低聚噻吩的增加对LUMO能级的调控作用较为显著, 而共轭桥的类型对HOMO能级影响较大; 合理选择端基、 共轭桥和连接臂等结构单元可对该类材料吸光波段及强度进行有效调节. 一维电荷传输模型结果表明, 所设计的化合物均是潜在的双极性有机半导体材料, 其中2,7-二([2,2':5',2'-三噻吩]-5-基)苯并[1,2-b:6,5-b']二噻吩(A3)和2,7-二(二噻吩并噻吩-2-基乙炔基)苯并[1,2-b:6,5-b']二噻吩(a-3)具有较高的电子迁移率, 值得进一步的实验探索研究.  相似文献   

7.
将冠醚引入到聚合物骨架上合成了一种聚合物分子主链上同时带有离子传导与电子传导链段的聚对亚苯基亚乙烯基功能性发光共聚物DB PV ,采用FT IR、1 H NMR、DSC、元素分析等手段对共聚物进行了表征 ,测定了共聚物的氯仿溶液和其膜的紫外吸收及其光致发光行为 .结果表明DB PV可溶于氯仿、吡啶等有机溶剂 ,具有良好的溶解成膜性与加工性能 ,是一种较理想的功能性蓝色发光材料  相似文献   

8.
An organic light‐emitting diode was fabricated using cadmium selenide (CdSe)/poly(N‐vinylcarbazole) nanocomposite as the hole transport layer (HTL). The CdSe nanoparticles (NPs) with a mean crystallite size of 6.2 nm were prepared by high‐energy ball milling. Based on the current–voltage curves, the threshold voltage (V th) of the composite diode was found to be ~1.3 ± 0.1 V lower than that of the diode without CdSe, with a significant increase in the current density for the composite diode. Moreover, the electroluminescence (EL) properties (luminous flux, emittance, and intensity) of the diode were found to be enhanced by ~16% with respect to those of the diode without CdSe. The decrease of the threshold voltage and the increase of the current density and the EL were due to the CdSe NPs that operate as hole trap centers in the HTL.  相似文献   

9.
不同电子传输层的蓝光有机电致发光器件的性能研究   总被引:6,自引:0,他引:6  
自从Tang等^[1]首次报道多层有机电致发光器件(OLED)以来,其在亮度和效率上有了质的飞跃,表明器件的结构对提高发光亮度和发光效率起着至关重要的作用,单层器件虽然具有制作简单的优点,但却存在明显缺点:(1)复合发光区靠近金属电极,该处缺陷很多,非辐射复合几率大,导致器件效率降低;(2)由于两种载流子注入不平衡,载流子的复合几率较低,因而影响器件的发光效率,要使发光层中具有高的载流子辐射复合效率,两种载流子的注入及传输能力应相当,否则传输快的一方就会直接穿过发光层到达对电极被猝灭,平衡电子和空穴的注入与传输可通过在电极和发光层之间加入载流子输运层或限制层制作多层器件的途径来实现,基于上述考虑,我们以PPCP为发光层(PPCP是一种荧光效率较高的蓝光材料^[2-4],对其进行深入研究尚未见有文献报道_,设计了4种不同电子传输层(ETL)的三层 结构的OLED,为研究电子传输层对器件性能的影响,我们还制备了不含电子传输层的双层器件,结果表明,通过选择合适的ETL,OLED的发光亮度及发光效率会有很大程度的改善。  相似文献   

10.
Summary: A class of new, soluble, π‐conjugated polymers containing a fumaronitrile unit in the main chain were synthesized by the reaction between di(4‐bromophenyl)fumaronitrile and bis(2,2‐dimethylpropane‐1,3‐diyl)‐1,4‐dialkoxyphenylene‐2,5‐diborate employing palladium catalysts. All the polymers were photoluminescent and electrochemically active.

The new soluble π‐conjugated polymers 1a – d with photoluminescence and electrochemical activity synthesized here.  相似文献   


11.
聚醚醚酮(PEEK)因具有优异的机械性能、耐热性、耐化学腐蚀性等优点而广泛应用于航空航天、电子器件、机械仪表等领域.具有刚性结构的聚醚醚酮有极好的耐溶剂性,不溶于一般的有机溶剂,并且需在较高的温度下进行加工.近20年来,人们不断开发性能优异的聚醚醚酮新材料,在聚合物主链上引入不同的功能基团(如萘环、氮杂萘环等)及侧基功能基团(如苯、三氟甲基等),以提高聚芳醚酮的溶解性,或者通过共聚和共混等方式进一步改善材料的使用性能和加工性能,  相似文献   

12.
A series of naphthyl‐substituted poly(p‐phenylenevinylene)s (2N‐PPV, 4N‐PPV, and NAP‐PPV) has been synthesized and characterized by Fourier transform IR, 1H NMR, and elemental analysis. The polymers possess excellent solubility, high molecular weights, good thermal stability, and high photoluminescence efficiencies. Thermogravimetric analysis reveals the onset of degradation to be 347, 301, and 306 °C for 2N‐PPV, 4N‐PPV, and NAP‐PPV, respectively. The differential scanning calorimetry investigation gives the respective glass‐transition temperature values of 118, 135, and 141 °C. The UV and photoluminescence spectra measurements reveal that the polymers exhibit similar optical properties, indicating that side‐chain substitution has little effect on the optical properties of this series of polymers. Proton NMR measurement of the signal due to tolane–bisbenzyl defects at around 2.7 ppm indicates that all the polymers have negligible amounts of tolane–bisbenzyl defects along the polymer main chain as a result of the steric bulk imposed by the naphthalene side chain. The highest occupied and lowest unoccupied molecular orbital energy levels of the polymers are investigated through cyclic voltammetry. Polymer light‐emitting diodes utilizing the polymers as the emissive layer with a configuration of indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer/Ba/Al are fabricated and evaluated. The diodes emit blue‐green to yellow‐green light with maximum peaks at 518, 542, and 486 nm for 2N‐PPV, 4N‐PPV, and NAP‐PPV, respectively. The respective turn‐on electric fields of the diodes are 0.84, 0.69, and 0.83 MV/cm and the respective maximum external quantum efficiencies are 0.08, 0.54, and 0.02%. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1647–1657, 2004  相似文献   

13.
《中国化学会会志》2018,65(2):243-251
A series of small organic molecules were synthesized by exploiting the bay and imide positions of the perylene nucleus. The synthesized compounds 1 – 11 were characterized by spectroscopic and elemental analyses. These molecules show yellowish color in solution and are highly soluble in dichloromethane. Compound 7 shows a bandgap of 1.7 eV and a Stokes shift of 27. From these results, we infer that this compound can serve as structural template in the design of organic electronics. Moreover, compound 7 shows higher Td (370°C) and Tg (132°C) values, which reflect its high thermal stability.  相似文献   

14.
Chromium(VI) is one of the major toxic elements present in environmental samples. The polymer inclusion membrane (PIM), has been developed to provide metal ion transport with high selectivity. This study was conducted to discover efficient methods for removing Cr(VI) from wastewater. A functionalized calix[4]arene carrier 1 in a PIM system was used to transport Cr(VI) from an acidic aqueous donor phase solution to an acceptor phase that contained an acetic acid/ammonium acetate solution at pH 6. The prepared PIM was characterized with Fourier Transform Infrared (FT-IR) spectroscopy and the Atomic Force Microscopy (AFM) techniques as well as with contact angle measurements. The efficiency of Cr(VI) transport through the PIM was investigated by studying the effects of carrier concentration on the membrane phase as well as by measuring the amount of plasticizer in the membrane, the pH in the acceptor phase and the membrane's stability and thickness. The kinetic parameters were calculated as rate constant (k), permeability coefficient (P), flux (J) and diffusion coefficient (Do). The transport efficiency of Cr(VI) was observed to be 98.61% after 10 h under optimized conditions. The experimental results show that Cr(VI) can transport from the donor phase to the acceptor phase with high efficiency through the PIM. The results also suggest that the transport efficiency of the PIM was reproducible and that a PIM is effective for long-term separation processes.  相似文献   

15.
杜松松  李春荣  赵春梅  魏妮  王文亮 《化学学报》2011,69(10):1151-1159
采用密度泛函理论(DFT, TDDFT) B3LYP/6-31G(d)和PBE0/6-31G(d)方法对苯乙烯/乙炔为端基, 二噻吩(2T)、苯并二噻吩(TPT)和二苯并噻吩(PTP)为共轭桥的12个化合物进行了系统地计算研究. 在分别优化中性态与离子态几何构型的基础上, 获得了前线轨道能级、电离能(IPs)、电子亲合能(EAs)、重组能(λh/λe)和电子吸收光谱等信息. 结果表明, 苯乙炔基取代苯乙烯基对LUMO能级影响很小, 但HOMO能级明显降低, 能级差?E和激发能Ev增大, 吸收光谱蓝移10~30 nm, 多数苯乙炔基化合物的重组能均有所降低|端基相同共轭桥分别为2T, TPT和PTP时, HOMO能级逐渐降低, LUMO能级逐渐升高, ?EEv依次增大, 吸收光谱依次蓝移30~45 nm. 研究结果还表明, TPT共轭桥化合物的重组能较小, 且λhλe相近, 有利于载流子传输平衡, 提高传输速率. 本文设计的苯乙炔基苯并二噻吩(DPATPT)有望成为潜在的传输效率高、抗氧化能力强的载流子传输材料.  相似文献   

16.
Three new poly(p‐phenylenevinylene)‐based polymers containing two 1,3,4‐oxadiazole moieties in the main chain per repeat unit were synthesized by Heck coupling. A single, double, or triple bond was introduced between the oxadiazoles to provide a means for modifying the polymer properties. The polymers were readily soluble in common organic solvents and showed Tg values lower than 50 °C. The color of the emissive light in both the solid state and the solution could be tuned by a change in the nature of the bond between the oxadiazole rings. The polymers emitted ultraviolet‐green light in solution with a photoluminescence (PL) emission maximum at 345–483 nm and blue‐green light at 458–542 nm in thin films. The PL quantum yields in solution were 0.36–0.43. The electrochemical properties are affected by the nature of the bond between the oxadiazoles as well. In polymers with a single bond between the oxadiazoles, a lower ionization potential was observed than in polymers with a double or triple bond. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3079–3090, 2005  相似文献   

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