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1.
Novel copolymers derived from amino‐functionalized fluorene‐ and selenium‐containing heterocycles [2,1,3‐benzoselenadiazole (BSeD)] were synthesized by the palladium‐catalyzed Suzuki coupling method. Their quaternized salt polyelectrolytes of corresponding compositions were obtained by a postpolymerization treatment. The resulting copolymers were soluble in polar solvents. An efficient energy transfer due to exciton trapping on the BSeD sites was observed. Devices from such copolymers emitted orange‐red light peaked at 560–610 nm. All the polymers showed good device performance with high‐work‐function metal Al as a cathode without the use of an additional electron‐injection layer and are promising candidates for polymer light‐emitting diode applications. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2521–2532, 2006  相似文献   

2.
采用Suzuki偶合反应合成了一系列新型的咔唑、芴和2,1,3-苯并硒二唑的共聚物——聚[3,6-(N-(2-乙基己基))咔唑-2,1,3-苯并硒二唑-9,9-双(N,N-二甲基胺丙基)芴](PCzN-BSeD)及其相应的聚电解质衍生物——聚[3,6-(N-(2-乙基己基))咔唑-2,1,3-苯并硒二唑-9,9-(双(3′-(N,N-二甲基)-N-乙基铵)丙基)芴]二溴(PCzNBr-BSeD).在聚咔唑和芴中引入不同比例的2,1,3-苯并硒二唑(BSeD)单元,引起了由咔唑和芴链段向窄带隙苯并硒二唑(BSeD)单元有效的能量转移.通过对聚合物电致发光性能的研究,发现用聚(3,4-亚乙基二氧基噻吩)(PEDOT)或聚(3,4-亚乙基二氧基噻吩)/聚乙烯咔唑(PEDOT/PVK)作为空穴传输层时,器件的性能相差不大,表明咔唑的引入较明显的改善了聚合物的空穴注入性能.而且几乎所有的聚合物用高功函数铝作阴极的器件和用钡/铝作阴极的器件具有相近的发光性能,表明这类聚合物具有良好的电子注入性能.  相似文献   

3.
Poly(phenylenevinylene‐alt‐fluorenevinylene) ( PF ) or poly(fluorenevinylene) ( F ) derivatives that carried alkyl chains with terminal tertiary amino groups were successfully synthesized via Heck coupling. They were postquaternized by reacting with bromoethane to the corresponding cationic polyelectrolytes PFQ and FQ . The neutral polymers PF and F as well as the quaternized polymer FQ were soluble in common organic solvents such as THF, chloroform, dichloromethane, and toluene. In contrast, the quaternized polymer PFQ did not dissolve in these solvents but was soluble in environmentally friendlier solvents like water and alcohols. The neutral precursors exhibited higher thermal stability and glass‐transition temperatures than the corresponding quaternized counterparts. All polymers emitted intense blue‐greenish light in solution (462–489 nm) with relatively high photoluminescence (PL) quantum yields 0.32–0.57, and as thin films (475–557 nm) with optical band gaps of 2.48–2.57 eV. The water soluble PFQ could find potential applications as chemo or biosensor. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1481–1491, 2007  相似文献   

4.
张凯  黄飞  曹镛 《高分子学报》2017,(9):1400-1414
相对于传统的无机半导体器件,以有机半导体(特别是聚合物半导体)材料为基础的有机光电器件,可采用与传统印刷技术(例如喷墨打印、卷对卷印刷等)相结合的溶液加工方式制备低成本、大面积、柔性光电器件,因而成为广泛关注的焦点,并得到了快速发展.实现溶液加工的高效有机光电器件的一个关键问题是界面问题——如何避免溶液加工时有机层间的互溶以及如何实现可印刷稳定金属电极的高效电子注入等.水/醇溶性共轭聚合物的迅速发展为解决溶液加工多层有机光电器件所面临的界面问题提供了有效手段.研究发现,水/醇溶共轭聚合物不但可以有效避免溶液加工多层器件中的界面互溶,而且还可与高功函数的稳定金属发生界面偶极相互作用而增强其电子注入,从而解决了高功函数稳定金属电子注入的难题,为实现全溶液加工的高效印刷有机光电器件提供了可行的方案.本文介绍了近年来本课题组在水/醇溶共轭聚合物阴极界面材料及器件应用方面的研究进展,并对水/醇溶共轭聚合物阴极界面材料在聚合物发光二极管和聚合物太阳电池中的工作机理进行了探讨.  相似文献   

5.
陈伯宽 《高分子科学》2010,28(4):607-613
<正>A new methacrylamide monomer,hexylamine methacrylamide(MAHA),was synthesized and used in polymerizations.The homopolymer of MAHA and its copolymers were synthesized by free radical polymerization techniques with N-isopropyl acrylamide(NIPAAm) in two different compositions.The quaternization of the homopolymer and copolymers were carried out using 1-bromopropane.The copolymers with NIPAAm and a low MAHA content showed temperature-responsive behavior in an aqueous environment.The lower critical solution temperatures(LCSTs) of these polymers varied between 32℃and 44℃.The LCSTs of quaternized copolymers were higher than those of neutral copolymers because they were more hydrophilic.The obtained homopolymers and copolymers were tested for antibacterial activities against S.aureus and E.coli.The quaternized water-soluble copolymers showed antibacterial activities against S.aureus.The quaternization resulted in the synthesis of both antibacterial and temperature-responsive copolymers.  相似文献   

6.
Poly(oxyethylene methacrylate)–poly(4-vinyl pyridine) (POEM–P4VP) comb-like copolymers with 3:7, 5:5, and 6:4 wt ratio were synthesized via atom transfer radical polymerization and confirmed by 1H-NMR and FT-IR spectroscopy. The copolymers were quaternized with 1-iodopropane to convert the pyridine groups into pyridinium ions, i.e., POEM–qP4VP. Transmission electron microscopy showed that strongly segregated microphase separation in POEM–P4VP was less prominent upon quaternization due to interactions between the ether oxygens of POEM and the quaternized pyridine groups of qP4VP, as confirmed by FT-IR spectroscopy. The energy conversion efficiencies of dye-sensitized solar cells (DSSCs) with quaternized polymer electrolytes were always greater than those with pristine electrolytes due to greater ionic conductivity and concentrations of free iodide ions. The maximum energy conversion efficiency of a DSSC employing POEM–qP4VP electrolyte reached 3.0% at 100 mW/cm2 when a 6:4 wt.% of POEM–qP4VP was used.  相似文献   

7.
Two novel polyphenylene and polyphenylenevinylene copolymers containing triarylpyrazoline units in the main chains were synthesized and characterized. The resulting copolymers were amorphous and showed excellent solubility in common organic solvents, such as dichloromethane, chloroform, 1,2‐dichloroethane, chlorobenzene, toluene, and THF. The polymers possessed good thermal stability with glass transition temperatures of 82 and 96 °C and decomposition onset temperatures of 295 and 309 °C, respectively. They exhibited good photoluminescence properties with high photoluminescence efficiencies. Double‐layered light‐emitting‐diode devices with an indium tin oxide/Poly(3,4‐ethylenedioxythiophene)/polymer/Ba/Al configuration could emit strong green light with external quantum efficiencies of0.53 and 0.92%. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1632–1640, 2007  相似文献   

8.
芴与噻吩发光共聚物的合成及其电致发光性能   总被引:9,自引:2,他引:9  
采用Suzuki偶合方法合成出了一系列新型的 9,9 二辛基芴 (DOF)和噻吩 (Th)的共聚物 .其中 ,DOF与Th的投料比 (摩尔比 )分别为 95∶5 (PTF5 )、90∶1 0 (PTF1 0 )、85∶1 5 (PTF1 5 )、70∶3 0 (PTF3 0 )、5 0∶5 0 (PTF5 0 ) .所有的聚合物均可溶于常用的有机溶剂 ,如THF,CHCl3等 ,其分子量在 60 0 0~ 5 3 0 0 0之间 .当在聚芴主链中引入噻吩后 ,其发光波长发生了红移 ,最大发光波长由PTF5时的 490nm红移到PTF5 0时的 5 41nm .随着聚芴主链中噻吩含量的增加 ,最大电致发光和光致发光效率都逐渐降低 由这些聚合物所制得的器件 ,最大电致发光效率为PTF5和PTF1 0的 0 45 %.由此表明 ,在聚芴主链中引入少量的低带隙单体噻吩可以调节聚芴的发光颜色及发光效率  相似文献   

9.
发展了新型含有胺基的支化烷基修饰的咔唑单元,并且与芴、咔唑、苯等单元通过Suzuki偶联反应共聚得到不同主链结构的水/醇溶共轭聚合物界面修饰材料,研究了主链结构的变化对材料光物理、电化学性能的影响.所有聚合物均被用作阴极界面材料应用于器件结构为ITO/PEDOT:PSS/P-PPV/界面层/Al的聚合物发光二极管中.在相同器件制备条件下,系统比较了不同主链结构的界面修饰材料在器件中的性能,并研究了性能差异的原因.器件研究结果表明,在高功函数金属Al阴极的聚合物发光二极管中,含胺基功能化咔唑单元的水/醇溶共轭聚合物材料由于界面偶极的形成,均表现出很好的电子注入/传输性能,与之对应的器件性能得到大幅提升.  相似文献   

10.
Soluble conjugated copolymers (PFN-TPA) derived from 2,1,3-benzothiadiazole (BTDZ), triphenylamine (TPA) and 9,9-bis(3′-(N,N-dimethylamino)propyl)fluorene (DMAPF) were synthesized by palladium(0)-catalyzed Suzuki coupling reactions. Optoelectronic properties of the copolymers were characterized by UV-vis absorption, cyclic voltammetry, photoluminescence and electroluminescence. All these copolymers show excellent EL performances in the devices with Ba/Al, Al and even Au as cathode and are promising candidate for fabrication and patterning of air-stable flat panel displays.  相似文献   

11.
Styrene was polymerized in the presence of benzoyl peroxide (BPO) and 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) to yield polystyrene-TEMPO (PS-TEMPO) macroinitiator. The PS-TEMPO macroinitiator with different molecular weight was reacted with 4-vinyl pyridine (4-VP) to synthesize polystyrene-block-poly(4-vinyl pyridine) (PS-b-PVP), which was then quaternized with n-octyl iodide. Antibacterial activity of the quaternized copolymers was assessed against a gram negative bacterium (Pseudomonas aeruginosa) and a gram positive one (Staphylococcus aureus) by using the shake flask test method, and the results were compared with those of poly(styrene-random-4-vinyl pyridine) (P(ST-r--VP)). The quaternized copolymers inhibited greatly the growth of the bacteria, and PS-b-PVP was more active than P(ST-r-VP), which was ascribed to the fact that the content of quaternized 4-VP units on the surface of the particles of the former copolymer was higher than that corresponding to the latter one.  相似文献   

12.
Statistical copolymers of 2‐hydroxyethyl methacrylate (HEMA) and 2‐diethylaminoethyl methacrylate (DEA) were synthesized at 50 °C by free‐radical copolymerization in bulk and in a 3 mol L?1 N,N′‐dimethylformamide solution with 2,2′‐azobisisobutyronitrile as an initiator. The solvent effect on the apparent monomer reactivity ratios was attributed to the different aggregation states of HEMA monomer in the different solvents. The copolymers obtained were water‐insoluble at a neutral pH but soluble in an acidic medium when the molar fraction of the DEA content was higher than 0.5. The quaternization of DEA residues increased the hydrophilic character of the copolymers, and they became water‐soluble at a neutral pH when the HEMA content was lower than 0.25. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2427–2434, 2002  相似文献   

13.
Polymers play an important role in hair cosmetics due to their ability to change the properties of the hair. In order to tailor the properties such as fixative power, wash‐out and elasticity, polymers are generated by smart choice of monomer composition and process technology. Up to the seventies, polyvinylpyrrolidone and its copolymers were dominant. In the seventies, copolymers of vinyl acetate with further monomers followed and copolymers of methyl vinylethers with maleic acid half esters. Polyquaternium compounds were developed (copolymers of vinyl pyrrolidone with quaternized vinyl imidazole or dimethylaminomethyl methacrylate)to ease the combing of hair. In the seventies and eighties, copolymers of acrylate monomers and their esters or alkylacrylamides were supplied. The latest developments aim for polymers with covalently bound silicon compounds in order to ease the demanding formulation work, or for polymers which allow a formulation with water as substitute for alcohol as solvent.  相似文献   

14.
The synthesis of diblock as well as gradient copolymers of N,N‐diethyl glycidyl amine (DEGA) with ethylene oxide (EO) via anionic ring‐opening polymerization is presented. The polymers exhibit low polydispersities (≤1.13) and molecular weights in the range of 3300–10 200 g mol−1. In PEG‐co‐PDEGA copolymers, incorporation of 4%–29% DEGA results in tailorable cloud point temperatures in aqueous solution and melting points depending on DEGA content. mPEG‐b‐PDEGA block copolymers can be quaternized to generate cationic double‐hydrophilic polyelectrolyte copolymers with polyether backbone. Furthermore, mPEG‐b‐PDEGA has been used as dual reducing and capping agent for gold nanoparticle synthesis.  相似文献   

15.
芴-噁二唑类聚合物的合成及光谱特性   总被引:2,自引:0,他引:2  
通过缩聚反应,制得了高分子量的线型和超支化的芴-噁二唑类聚合物.它们均可溶于常用的有机溶剂。在固态薄膜时,它们的紫外-可见光吸收光谱在大约398nm和376nm处有两个强的吸收峰。它们的薄膜PL光谱在蓝光波长范围内有强发射峰,薄膜PL效率约为16%。电化学测试显示它们的的LUMO能级比芴的均聚物高,而与钙、镁这样典型的阴极材料的功函数较接近.这表明此类聚合物具有较好的电子注入和传输性能。  相似文献   

16.
A series of alcohol soluble amino-functionalized carbazole-based copolymers were synthesized via Suzuki coupling reaction.The pendent amino groups endow them high solubility in polar solvents,as well as efficient electron injection capability from high work-function metals.The relationships between the photophysical and electrochemical properties and the polymer backbone structure were systematically investigated.These alcohol-soluble carbazole-based copolymers were used as cathode interlayers between the high work-function metal Al cathode and P-PPV emissive layer in polymer light-emitting diodes with device structure of ITO/PEDOT:PSS/P-PPV/interlayer/Al.The resulting devices exhibited improved performance due to the better electron injection/transporting ability of the designed copolymers from Al cathode to the light-emitting layer.  相似文献   

17.
氯甲基化苯乙烯-二乙烯苯共聚物在傅氏催化剂存在下与取代酚(芳香胺)反应可以得到一些含取代酚基的离子交换树脂。它们的物理化学性质和红外光谱分析证实了该类树脂的结构。溶剂的性质、催化剂的种类、用量、反应温度、时间、取代酚(芳香胺)的取代基位置、聚合物的含氯量和孔结构都对反应和副反应有明显的影响。这类离子交换树脂在重金属分离、脱色,特别在维生素和抗菌素的选择吸附等方面,都有十分重要的意义。  相似文献   

18.
Abstract

Five laboratory solvent extraction methods for the determination of leachable trace metals from municipal incinerator fly and bottom ashes are evaluated. The trace elements of interest were cadmium, chromium, copper, manganese and lead. Five different extractants, 0.1NHCl, 1.0 N ammonium acetate, methyl isobutyl ketone (MIBK), chloroform and hexane were used on each ash to determine comparative extraction efficiencies.

Extraction efficiencies of the five solvents were determined based on total metal concentration, and were found to rank in the following order: 0.1NHCl<1.0N ammonium acetate < MIBK < chloroform < hexane. No one solvent was optimal for obtaining environmentally available values for all five metals. The inorganic solvents, 0.1NHCl and 1.0N ammonium acetate, exhibited higher removal of trace metals from ash particles relative to the organic solvents. Manganese concentrations were removed more efficiently by 0.1NHCl, whereas 1.0 N ammonium acetate was more efficient for removing copper concentrations. Cadmium, Cr, and Pb could effectively be extracted by either of the two inorganic solvents. Concentrations of trace metals extracted from refuse ash appeared to be a function of the elemental boiling point and the species that exist on combustion. However, the classification of elements for refuse ash in this study strayed somewhat from the traditional geochemical classification scheme into which coal ash is placed.  相似文献   

19.
含羧基的含氟嵌段共聚物的合成及表面性能研究   总被引:6,自引:0,他引:6  
利用原子转移自由基聚合反应以及随后的大分子链中叔丁酯基团的水解反应,合成了一系列具有不同含氟量和羧基含量的二嵌段共聚物,并分别通过GPC, 1H NMR和FT-IR对共聚物的组成和结构进行了表征.进一步考察了这些含羧基或羧酸钠基团的含氟嵌段共聚物在吡咯烷酮或水中的溶解性能、临界胶束浓度、表面活性、达到饱和吸附时每个分子在表面所占据的面积,以及成膜后的临界表面张力等性能.实验结果表明,此含氟嵌段共聚物能显著降低吡咯烷酮和水的表面张力,成膜后表现出与聚四氟乙烯极为接近的低表面能特性.  相似文献   

20.
Grafting of 4-Vinyl Pyridine onto Nylon-6 Initiated by Redox System   总被引:1,自引:0,他引:1  
The graft copolymerization of 4‐vinyl pyridine (4VP) onto nylon‐6 (PA6) was studied by using potassium diperiodatonickelate(IV) (DPN)‐PA6 redox system in alkaline medium. The structures of graft copolymers were confirmed by Fourier transfer infrared spectroscopy (FTIR) and X‐ray diffraction. The properties of graft copolymers were investigated by thermogravimetric analysis (TGA). A mechanism was proposed to explain the generation of radicals and the initiation. The effects of reaction variables, such as the initiator concentration, the ratio of 4VP to PA6, pH as well as reaction temperature and time were investigated. Graft copolymers with high grafting efficiency (>95%) were obtained, which indicated that DPN‐PA6 redox system is an efficient initiator for this graft copolymerization. The quaternized PA6‐g‐P4VP (QPAVP) was proved to be an excellent adsorbent to heavy metal ions.  相似文献   

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