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1.
通过控制缩合反应物中溴取代基的位置,得到了3种基于螺(芴-9,9'-氧杂蒽)的单体.利用Suzuki 偶联反应得到3种蓝光聚合物CSSFX,USSFX和DSSFX.聚合物USSFX和DSSFX具有较高的玻璃化转变温度和热分解温度.3种聚合物表现出较低并且相近的最高占有轨道能级(-5.80 eV至-5.93 eV)和最低未占有轨道能级(-2.80 eV至-3.01 eV).螺(芴-9,9'-氧杂蒽)单元的引入可降低聚合物DSSFX的最低未占有轨道能级到-3.01 eV,同时降低聚合物USSFX的最高占有轨道能级到-5.93 eV,聚合物USSFX较低的最高占有轨道能级使其具有较好的空穴注入性能.不同气氛下的高温退火实验表明,聚合物USSFX即使在空气中长时间高温退火以后,仍能保持稳定的蓝光发射.不同拓扑结构螺(芴-9,9'-氧杂蒽)单元的引入,可以有效调节蓝光聚合物的综合发光性能.  相似文献   

2.
通过Suzuki偶合反应合成出了主链中含有非共轭烷氧基组分(-O-CH2-CH2-CH2-CH2-O-)的聚芴类衍生物聚- 2,7-(9,9-二辛基芴)-co-4,4’-丁氧基二苯(PFP)和聚-2,7-(9,9-二辛基芴)-co-4,4’-丁氧基二苯-co-N-苯基-4,4’-二苯胺(PFTP11)并通过相同的条件合成出主链由芴和三苯胺交替相连的聚合物聚-2,7-(9,9-二辛基芴)-co-N-苯基-4,4’-二苯胺(PFTPA)作为参比材料. 通过1H NMR和FT-IR分析对这些聚合物的化学结构进行了表征. 这三种聚合物在常用的有机溶剂中具有很好的溶解性, 可通过溶液加工的方式制备聚合物薄膜. 这些聚合物均具有较高的热分解温度(>400 ℃), 聚合物PFP具有较高的玻璃化转变温度(~130 ℃)而PFTP11和PFTPA则未出现明显的玻璃化转变过程. 通过对聚合物的吸收特性进行测试得知它们具有较大的光学带宽(2.89~3.29 eV). 所有聚合物在固体薄膜状态下均发射出蓝色荧光, PFP, PFTP11和PFTPA的最大PL发射分别位于425, 437和440 nm. 通过对其电化学性能进行测试可知由于三苯胺基团的引入聚合物的HOMO能级明显提高, 这意味着聚合物的空穴传输能力得到了有效的改善.  相似文献   

3.
设计合成了三种基于2,4,6-三苯基-1,3,5-三嗪和芴单元的双极性主体材料FTRZ, p TFTRZ和mTFTRZ.分别研究了它们的热稳定性、光物理性能、电化学性质和电致发光器件性能与分子的拓扑结构之间的关系.FTRZ,p TFTRZ和mTFTRZ的热分解温度均在400℃以上,p TFTRZ和mTFTRZ的玻璃化转变温度分别是103和120℃.化合物FTRZ,p TFTRZ和mTFTRZ在甲苯溶液中的光学带隙分别为3.24,3.29和3.24eV,它们的三重态能级分别为3.04,3.11和3.05 eV.由于2,4,6-三苯基-1,3,5-三嗪平面间的π-π作用,化合物FTRZ, p TFTRZ和mTFTRZ在薄膜状态下形成激基缔合物,荧光发射光谱明显红移.最后研究了FTRZ, p TFTRZ和mTFTRZ作为客体发光分子2,4,5,6-四(9-咔唑基)-间苯二腈的主体材料在绿色热活化延迟荧光电致发光器件中的应用.以化合物FTRZ作为主体材料的绿色有机电致发光器件(OLED)表现出更好的电致发光性能,最大电流效率为6.7cd/A,最大外量子效率为2.07%,最大亮度为35718 cd/m~2,远优于以p TFTRZ和mTFTRZ作为主体材料的绿光器件.  相似文献   

4.
通过Suzuki偶合反应合成了一系列胺烷基侧链取代的基于三苯胺和芴的共轭聚合物聚[4-(N,N-二甲基胺丙氧基)苯-4,4′-二苯胺-9,9-二辛基芴-4,7-二噻吩-2-基-2,1,3-苯并噻二唑](PFTD), 并对其化学结构和光电性能进行了表征. 末端胺基的存在提高了此类聚合物作为发光层应用于聚合物电致发光器件的性能(采用高功函数的金属铝作为阴极时). 结构为ITO/PVK/PFTD-5(DBT摩尔分数为5%时的聚合物)/Al的器件最大电致发射峰位于647 nm, 最大外量子效率达到了1.24%.  相似文献   

5.
设计合成了一种基于三嗪类的新型双极性蓝色磷光主体材料[4-(4,6-二-α-萘氧基-1,3,5-三嗪-2-基)苯基]9-咔唑(NOTPC),并对其结构进行了表征。通过紫外-可见(UV-Vis)吸收、荧光、低温磷光、循环伏安法、热重分析(TGA)、差热分析(DSC)和密度泛函理论(DFT)对其性能及结构进行了研究。结果表明,NOTPC在CH2Cl2稀溶液中的吸收峰位于341和374 nm;发射峰位于478 nm;NOTPC的低温(77 K)磷光光谱的第一发射峰位于442 nm,其三线态能级为2.80 eV,与蓝色磷光材料FIrpic(2.62 eV)的能级相匹配;NOTPC的HOMO主要分布在苯基咔唑单元,而LUMO主要定域在三嗪环上。其HOMO能级为-5.40 eV,与阳极ITO的功函(-4.5~-5.0 eV)相匹配,LUMO能级为-2.32 eV,接近于电子传输材料PBD(-2.82 eV),NOTPC表现出双极传导性能, 且热稳定性良好。  相似文献   

6.
通过Suzuki偶合反应得到了两种间位连接的三苯基吡啶同分异构体和9,9-二辛基芴的交替共聚物PFOTPP1和PFOTPP2.并对它们的紫外-可见吸收光谱、光致发光光谱以及电化学性能等进行了初步研究.结果表明,将间位连接的三苯基吡啶基引入聚芴主链能使聚合物的LUMO能级降低,光致发光光谱发生蓝移,得到了两种有望应用于电致炼光发光器件的共轭聚合物蓝光发光材料.  相似文献   

7.
张晓云  赵蓓  吴伟 《合成化学》2013,21(3):336-338,341
以芴为原料,经溴代和氧化反应制得2,7-二溴芴酮(3);3与苯酚反应合成2,7-二溴-9,9-双(4’-羟基苯基)芴(4);4与3-(6’-溴己氧基甲基)-3-乙基氧杂环丁烷经醚化反应合成了可光固化单体2,7-二溴-9,9-双[4’-(3″-乙基-3″-氧杂环丁烷甲氧基己基氧基)苯基]芴,总收率67%,其结构经1H NMR,13C NMR和元素分析表征。  相似文献   

8.
通过Suzuki偶合反应合成出由苯乙炔悬挂取代的芴-三苯胺类交替共轭聚合物聚(9,9-二辛基-2,7-芴-共-N-4-苯乙炔-4,4'-三苯胺)(PFT-PE),并通过NMR和FT-IR对其化学结构进行了表征。结果表明:该聚合物易溶于常用的有机溶剂,可通过溶液旋涂的方式进行薄膜制备。由PFT-PE薄膜的吸收起始波长可知其光学带宽为2.82 eV。其薄膜较溶液态的荧光光谱发生了显著的红移并且变宽,说明在固态下聚合物分子链间发生了一定的堆积。由其电化学起始氧化电位可知PFT-PE的最高能量占有轨道能级(HOMO)为-5.39 eV,其氧化过程具有高度的可逆性,说明该聚合物具有良好的电化学稳定性。悬挂炔键功能团的存在使得该聚合物无需外加引发剂即可在一定温度下发生分子间的交联反应。  相似文献   

9.
以"马鞍型"环八四噻吩(COTh)与1,3,5-三嗪为构筑模块,通过Kumada类型反应有效地制备了三种分别含有1~3个COTh结构单元的环八四噻吩-三嗪衍生物,即2,4-二甲氧基-6-(5,8,11-三甲基硅基)-环八[1,2-b:4,3-b':5,6-b':8,7-b'']四噻吩-1,3,5-三嗪(1),2-甲氧基-4,6-二{(5,8,11-三甲基硅基)-环八[1,2-b:4,3-b':5,6-b':8,7-b'']四噻吩}-1,3,5-三嗪(2)和2,4,6-三{(5,8,11-三甲基硅基)-环八[1,2-b:4,3-b':5,6-b':8,7-b'']四噻吩}-1,3,5-三嗪(3).理论计算表明了该类化合物的长波长的两个吸收峰来自于分子内的电荷转移(CT)吸收.在溶液相它们发射分子内电荷转移(ICT)态荧光,峰位在560~570nm.而在冻结态下呈双荧光发射,即短波长的环八四噻吩本征态发光(400 nm)与长波长的ICT发光(480~500 nm).在四氢呋喃(THF)-H2O二元溶剂体系中,该类化合物产生聚集诱导发光(AIE)现象,可能与化合物分子同时受分子内旋转受阻(RIR)与分子内振动受阻(RIV)机制控制有关.单晶数据表明,化合物1分子内噻吩环与三嗪环之间呈现近平面构象.相邻分子之间噻吩环上的碳原子与三嗪环上的碳原子存在C-C相互作用,制约着连接分子内噻吩环与三嗪环之间单键的自由旋转,从而一定程度上制约了非辐射失活过程,有利于AIE现象的产生.  相似文献   

10.
含噻吩单元的硅芴共聚物的合成及其蓝色电致发光性能   总被引:1,自引:0,他引:1  
将少量(摩尔分数为1%—3%)含噻吩的窄带隙单体和宽带隙硅芴单体进行共聚, 合成了聚{9,9-二己基-3,6-硅芴-co-[2,5-二(2-甲基苯撑-4-基)-噻吩]}和聚{9,9-二己基-3,6-硅芴-co-[2,5-二(2-苯撑-4-基)-噻吩]}两类硅芴共聚物, 通过紫外-可见吸收光谱、光致发光光谱, 并制作聚合物发光二极管器件测试电致发光光谱等手段, 系统表征了两类硅芴共聚物材料的性能. 实验结果表明, 噻吩的加入形成了新的蓝色发光中心, 并且实现了从硅芴链段到含噻吩发光中心的有效能量转移. 通过增加发光中心结构的空间位阻来减小其共轭程度, 可以使聚合物的PL和EL光谱发生较大蓝移. 最终得到了效率为0.46%和色坐标(CIE)为(0.19, 0.16)的蓝光LED器件.  相似文献   

11.
A series of new hyperbranched polymers containing a 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine core unit and polyfluorene chain arms have been synthesized via Suzuki coupling, and characterized by NMR, IR and GPC. All the polymers exhibit good thermal stability with a high decomposition temperature. By changing the 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine/fluorene ratio the UV-vis absorption and emission spectra can be partially tuned. It has been found that the polymers containing a low ratio of 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine units (P1-P3) have an absorption maximum around 385 nm, localized in the polyfluorene chain, and a shoulder around 425 nm ascribable to a charge transfer state involving the fluorene and the 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine core. Increasing the molar ratio of the 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine unit enhances the charge transfer band which becomes dominant for P4. The LUMO level of these polymers is relatively low due to the electron affinity of the triazine group. The polymers show dual emission, with a structured band in the blue (410-440 nm), attributed to the polyfluorene, and a broad band in the red (470-500 nm) associated with the charge transfer state. All the polymers exhibit two-photon absorption activity in the range of 660 to 900 nm with the maximum two-photon absorption (TPA) cross-section red-shifted from the corresponding linear absorption. The values of the TPA cross-sections vary from 1000 to 5000 GM, following the 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine/fluorene ratio.  相似文献   

12.
The synthesis and characterization of two donor acceptor type conjugated polymers were investigated. Electrochemical properties were examined by cyclic voltammetry, spectroelectrochemistry and kinetic studies. The increase in the alkyl chain length attached to the fluorene unit was investigated in terms of electrochemical properties. The synthesis was carried out via Stille coupling of 4,7-dibromo-4′-(tert-butyl)spiro[benzo[d]imidazole-2,1′ cyclohexane] and 2,5-bis(tributylstannyl)thiophene with 9,9-dihexyl-9H fluorine (P1) and 9,9-didodecyl-9H fluorene (P2) respectively. Both polymers were neutral state green polymers. They had optical band gaps of 1.55 and 1.47 eV respectively. Increasing the chain length resulted in an increase in solubility and processibility of the polymer. Polymers are multichromic, revealing colors from neutral state green to doped state blue.  相似文献   

13.
Novel fluorene-based poly(aromatic diacetylene)s have been synthesized by CuCl-catalyzed oxidative coupling of aromatic diynes.New aromatic diynes 2,7-diethynyl-9,9-bis(triphenylamine)fluorene(M_1)is synthesized by multistep reactions.The structures and properties of the polymers are characterized and evaluated by IR,NMR,TGA,UV, photoluminescence(PL),and cyclic voltammetry analyses.These polymers possess good thermal stability.All the polymers are completely soluble in coammon solvents such as toluene,TH...  相似文献   

14.
ESCA has been used to investigate the composition and structural features of plasma-polymerized 2,4,6-trifluoro-1,3,5-triazine. Polymer formation was studied as a function of power and post-polymerisation treatment. All the polymer films revealed an intense peak at a binding energy of ~290.2 eV probably arising from groups. A high sensitivity towards hydrolysis was observed resulting in substantial loss of fluorine and increase in oxygen content of the plasma polymers.  相似文献   

15.
C3-symmetric alkyloxy/aryloxy polyether dendrimers have been synthesized from 1,3,5-triphenylbenzene and 2,4,6-triphenyl-1,3,5-s-triazine and their liquid crystalline properties have been studied. C3-symmetric derivatives with n-hexyl and n-dodecyl chains at the periphery show mesophase properties when they are complexed with trinitrofluorenone at different temperatures.  相似文献   

16.
Conclusions A study was made of the cyclotrimerization of benzonitrile in chlorosulfonic acid and the optimum conditions were ascertained for the formation of 2,4,6-triphenyl-1,3,5-triazine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2105, September, 1972.  相似文献   

17.
A carbazole homopolymer and carbazole copolymers based on 9,9'-dialkyl-[3,3']-bicarbazolyl, 2,5-diphenyl-[1,3,4]-oxadiazole and 9,9-bis(4-[3,7-dimethyloctyloxy]phenyl)fluorene were synthesized and their electrical and photophysical properties were characterized with respect to their application as host in phosphorescent polymer light-emitting diodes. It is shown that the triplet energy of a polymer depends on the specific connections between its building blocks. Without changing the composition of the polymer, its triplet energy can be increased from 2.3 to 2.6 eV by changing the way in which the different building blocks are coupled together. For poly(9-vinylcarbazole) (PVK), a carbazole polymer often used as host for high-energy triplet emitters in polymer light-emitting diodes, a large hole-injection barrier of about 1 eV exists due to the low-lying HOMO level of PVK. For all carbazole polymers presented here, the HOMO levels are much closer to the Fermi level of a commonly used anode such as ITO and/or a commonly used hole-injection layer such as PEDOT:PSS. This makes high current densities and consequently high luminance levels possible at moderate applied voltages in polymer light-emitting diodes. A double-layer polymer light-emitting diode is constructed comprising a PEDOT:PSS layer as hole-injection layer and a carbazole-oxadiazole copolymer doped with a green triplet emitter as emissive layer that shows an efficacy of 23 cd/A independent of current density and light output.  相似文献   

18.
A new series of fluorene‐based polyquinoxalines with an ether linkage in the main chain were prepared by the polycondensation reaction between a tetraketone monomer and 3,3′,4,4′‐tetraaminodiphenyl ether. The polycondensation was usually carried out in m‐cresol. The resulting polymers ( P1 – P3 ) [ P1 = poly(quinoxaline‐co‐9,9‐dihexyl‐2,7‐dimethyl‐9H‐fluorene) P2 = poly(quioxaline‐co‐9,9‐dihexyl‐9‐pentyl‐2,7‐di‐p‐tolyl‐9H‐fluorene) P3 = poly(quioxaline‐co‐9,9‐bis‐(4‐methoxy‐phenyl)‐2,7‐dimethyl‐9H‐fluorene)] showed good solubility in common organic solvents and high thermal stability with only a 5% weight loss up to 440 °C. P1 and P2 had very high glass‐transition temperatures of 212 and 223 °C, respectively, whereas P3 did not show any phase‐transition temperature in repeated scans up to 300 °C. All the polymers in photoluminescence showed blue emissions in the range of 432–465 nm, both in chloroform solutions and in thin films. Light‐emitting diode devices of the configuration indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer:poly(N‐vinylcarbazole) blend (2:8)/LiF/Al were fabricated with P1 or P2 and emitted blue light with electroluminescence peak wavelengths of 434 and 448 nm, respectively. The maximum brightness and the external quantum efficiency of P1 were 0.56 μW/cm2 at 29 V and 0.056%, whereas P2 showed 0.50 μW/cm2 at 34 V and a relatively low value of 0.015%, respectively. Cyclic voltammetry studies revealed that these polymers possessed low‐lying ionization potential energy levels ranging from ?5.49 to ?5.86 eV and low‐lying electron affinity energy levels ranging from ?2.65 to ?2.88 eV. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1189–1198, 2006  相似文献   

19.
A series of novel, fluorene‐based conjugated copolymers, poly[(9,9‐bis{propenyl}‐9H‐fluorene)‐co‐(9,9‐dihexyl‐9H‐fluorene)] ( P1 ), poly[(9,9‐bis{carboxymethylsulfonyl‐propyl}fluorenyl‐2,7‐diyl)‐co‐(9,9‐dihexyl‐9H‐fluorene)] ( P2 ) and poly[(9,9‐dihexylfluorene)‐co‐alt‐(9,9‐bis‐(6‐azidohexyl)fluorene)] ( P3 ), are synthesized by Suzuki coupling reactions and their electrochemical properties, in the form of films, are investigated using cyclic voltammetry. The results reveal that the polymer films exhibit electrochromic properties with a pseudo‐reversible redox behavior; transparent in the neutral state and dark violet in the oxidized state. Among the three polymers, P2 possesses the shortest response time and the highest coloration efficiency value. These polymers emit blue light with a band gap value of around 2.9 eV and have high fluorescent quantum yields. Their metal ion sensory abilities are also investigated by titrating them with a number of different transition metal ions; all of these polymers exhibit a higher selectivity toward Fe3+ ions than the other ions tested with Stern–Volmer constants of 4.41 × 106M?1, 3.28 × 107M?1, 1.25 × 106M?1, and 6.56 × 106M?1 for P1 , P2 , water soluble version of P2 ( P2S ) and P3 , respectively. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

20.
Radicals formed in γ-irradiated 1,3,5-trithiane and its derivatives at room temperature have been studied by ESR spectroscopy. ESR evidence establishes that 1,3,5-trithiane as well as α- and β-2,4,6-trimethyl-1,3,5-trithiane yield radicals mainly by loss of the hydrogen atom, whereas α- and β-2,4,6-triphenyl-1,3,5-trithiane and 2,4,6-trimethyl-2,4,6-triphenyl-1,3,5-trithiane produce radicals that are parent radical cations, which are also present in small amounts in aliphatic trithianes. Furthermore, in all the spectra examined R–S.-type radicals are observed. The probable initiation process of radiation-induced 1,3,5-trithiane polymerization is discussed briefly.  相似文献   

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