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1.
采用不同方法由三铳盐合成新型的聚电解质前聚物及可溶于有机溶剂的侧链溴代聚对苯乙炔前聚物,发现侧链烷氧取代基上的铳盐并不参与聚合,所得前聚物加热都可转化为聚对苯乙炔。  相似文献   

2.
采用紫外-可见光谱跟踪用直接聚合法制备可溶性的聚对苯乙炔衍生物的反应过程,结果表明反应仍然经历了生成前聚物的过程。控制反应条件使聚合反应首先生成前聚物,在前聚物烯化反应阶段加入起增溶作用的长链醇,得到了具有良好的溶解性的、主链中含非共轭链段的聚对苯乙炔衍生物。用该聚合物制备的电致发光器件,在5-6V电压驱动下发光,发光峰位于580nm左右。  相似文献   

3.
以4,4'-二取代联苯(或4,4'-二取代二苯甲烷)为原料合成了几种新的3,7-二取代二苯并环状溴(鎓)盐.对几种溴(鎓)盐与KBH4及与NaN3的反应进行了研究.结果表明,前一反应主产物为2-溴-4,4'-二取代联苯(或2-溴-4,4'-二取代二苯甲烷),后一反应的主产物为2-叠氮基-2'-溴-4,4'-二取代联苯(20a-20d).通过20a-20d的热反应合成几种新的多取代咔唑(21a-21d).  相似文献   

4.
在本研究工作中,我们发展了通过溴丙炔(propargyl bromide)分别与喹啉(quinoline)、吖啶(acridine)直接反应来制备聚溴化炔丙基喹啉[poly(propargyl quinolinium bromide),PPQB]和聚溴化炔丙基吖啶[poly(propargyl acridinium bromide),PPAB]的新方法. PPQB与PPAB的主链均为聚乙炔结构,侧链分别为季铵化喹啉盐和吖啶盐基团,是一类单取代的聚电解质型聚乙炔(polyelectrolyte polyacetylenes,PE-PAs). 我们提出了上述反应的机理,即溴丙炔与喹啉或吖啶反应生成季铵盐产物并导致产物结构中炔基基团的活化,使得季铵盐发生自聚合反应生成PPQB或PPAB. PPQB及PPAB具有较高的分子量(PPQB及PPAB的分子量分别为1.8×105和8.1×104 g/mol). 进一步的表征表明,PPQB和PPAB均具有良好的荧光活性和导电性能.  相似文献   

5.
利用钯催化反应合成了一类侧链含不同烷氧取代基(甲氧基,辛烷氧基,十二烷氧基)的聚时苯撑乙炔,讨论了侧链烷氧取代基对聚对苯撑乙炔的分子量和溶解性的影响,比较了聚合物的紫外吸收光谱和荧光光谱特征。  相似文献   

6.
通过功能化聚对苯撑乙炔(含羟基与氨基)和聚丙烯酸之间的非共价键自组装制备了一系列含共轭聚合物的水溶性荧光纳米粒子, 并进行了相关结构和光学性质表征. 研究表明, 纳米粒子的大小和聚丙烯酸/聚对苯撑乙炔质量比直接相关. 光物理性质研究表明, 形成水溶性纳米粒子后, 疏水的聚苯撑乙炔链在纳米粒子中易于形成π-链间聚集, 其光物理性质与其在薄膜态时相似.  相似文献   

7.
聚二乙炔(polydiacetylenes)具有平面的全共轭主链,并可被制备成宏观大小的单晶,因而是研究聚合物物理、化学性质的理想模型.它的物理、化学性质,特别是作为导电材料的导电机理与其价带及导带的结构密切相关.通过改变聚二乙炔的侧基可以对其主链几何结构及电子能带结构产生影响,进而改变其物理化学性质.可能是考  相似文献   

8.
聚硅乙炔烷的合成与性能研究   总被引:2,自引:1,他引:1  
70年代初苏联学者首次报道了聚硅乙炔烷的合成[1],1973年有人用炔化钙和二甲基二氯硅烷在熔融盐中反应,结果得到四环体物(Me2SiC≡C)4[2]。为了研究这类聚合物的性能,我们采用了新的合成路线合成可熔的聚硅乙炔烷。乙炔和格氏试剂发生交换反应,生成炔基双格氏试剂,它和有机二氯硅烷发生缩聚反应,生成聚硅乙炔烷。  相似文献   

9.
合成了含有苯乙炔基的二胺单体 3,5-二氨基-4'-苯乙炔苯甲酮(DPEB), 并与3,3',4,4'-联苯四酸二酐(s-BPDA)和1,4-双(4'-氨基苯氧基)-2-(苯基)苯(p-TPEQ)进行了缩聚反应, 以4-苯乙炔苯酐作为封端剂, 合成了交联侧基苯乙炔封端酰亚胺预聚体(n=4). DSC测试结果表明, 引入交联侧基后预聚体依然保持着较宽的加工窗口. 利用所合成的预聚体在370℃热压1 h制备了热固性薄膜. DMA测试结果表明, 引入交联侧基的预聚体树脂具有更高的玻璃化转变温度, 并且其储存模量在玻璃化转变后有很好的保持.  相似文献   

10.
报道了一种阻隔型聚对幕撑乙炔((PPE)的合成与电致发光特性,合成的模型小分子证明,在聚对苯撑乙炔(PPV)主链引入间位幕环,可阻隔PPV的有效共轭长度,改变其发光颜色,研究了电致发光暑件ITO/m-PPE/Al的电致发光特性。  相似文献   

11.
The highly conjugated aromatic polymers, poly(2,5-dimethoxyphenylene vinylene) and poly(2,5-dimethylphenylene vinylene), were obtained from their water soluble, sulfonium salt precursor polymers. Films of these polymers were reacted with either AsF5 or I2 vapor. Poly(2,5-dimethoxyphenylene vinylene) showed increases in electrical conductivity of up to 14 to 15 orders of magnitude for these two dopants, while an 8 to 9 order of magnitude increase was observed for poly(2,5-dimethylphenylene vinylene) with the same dopants. The synthesis of the precursor polymers, the properties and elimination reactions of films of the precursors, the doping reactions, and the conductivities of the resulting phenylene vinylene films are discussed.  相似文献   

12.
The new poly(arylene vinylene) derivatives, which are composed of biphenylene vinylene phenylene vinylene, biphenylene vinylene m‐phenylene vinylene, terphenylene vinylene phenylene vinylene, and terphenylene vinylene m‐phenylene vinylene as backbone and bulky fluorene pendants at each vinyl bridge, were designed, synthesized, and characterized. The obtained polymers showed weight‐average molecular weights of 11,100–39,800 with polydispersity indexes ranging from 1.5 to 2.1. The resulting polymers were amorphous with high thermal stability and readily soluble in common organic solvents. The obtained polymers showed blue emission (λmax = 456–475 nm) in PL spectra, and polymer 4 containing terphenylene vinylene m‐phenylene vinylene showed the most blue shifted blue emission (λmax = 456 nm). The double layer light‐emitting diode devices fabricated by using obtained polymers as emitter emitted bright blue light. The device showed turn on voltage around 6.5 V and brightness of 70–250 cd/m2. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4923–4931, 2006  相似文献   

13.
The conversion of the precursor into poly(phenylene–vinylene) (PPV) was studied by means of photoelectron spectroscopy (XPS) and electron spin resonance (ESR) on precursor films synthesized from the polymerization of pxylene-tetrahydrophenium halides. The sulfonium precursor containing chlorine or bromine was thermally converted to PPV and analyzed in situ using the spectrometers. It was found by XPS analysis that both halide precursors were thermally converted into polymer in a range of 190–250°C but traces of bromine were still present at >300 °C in the precursor containing Br. Furthermore, a small amount of oxygen in a ketone structure was also present in fully converted films. The ESR results corroborated the XPS experiments, showing a progressive disappearance of the radical distribution related to sulfur sites in a comparable temperature range. A discussion of the conversion process is given in terms of the modification of the core level spectra from XPS and the g distributions from ESR experiments. © 1997 John Wiley & Sons, Ltd.  相似文献   

14.
Poly(p‐phenylene vinylene) or PPV is gaining increasing importance because of its superior electroluminescent efficiency and electrical conductivity. The most widely followed synthetic route for PPV involves synthesis of a precursor polymer using a sulfonium monomer salt. Previous studies have proven that the monomer salt which contains cyclic sulfonium groups yields better quality PPV than when the monomer containing dialkyl sulfonium groups is used. The structure of PPV synthesized using cyclic sulfonium precursor has not been as widely reported as that synthesized using dialkyl sulfonium monomer. In the current work, the structure of PPV, synthesized using a cyclic viz. tetrahydrothiophenium monomer salt, has been studied in detail using the wide angle X‐ray diffraction (WAXD) technique. The study reveals that even in the cast (unstretched) form, PPV shows considerable biaxial orientation in the plane of the film. This preferred orientation is found to occur during the casting process and is independent of the solvent used and casting substrate. On stretching these films to a final draw ratio of 7 : 1, this biaxial orientation is transformed into uniaxial orientation with nematic ordering of PPV chains along the stretch direction and PPV chains assuming three preferred orientations in the plane of the film. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 605–614, 1999  相似文献   

15.
Two new types of p-xylene bis-sulfonium chloride monomers were prepared from cycloalkylene sulfides. The polymerization characteristics of these monomers to form poly(p-xylene sulfonium chlorides), and the thermal elimination reactions of their polymers to poly(p-phenylene vinylene), were compared with those of two monomers prepared from dialkyl sulfides. The cycloalkylene sulfonium chloride monomer polymerized to higher yields and to higher molecular weight polymers, which showed more efficient elimination reactions.  相似文献   

16.
This article reports on the synthesis, characterization, and properties of various anthracene‐containing poly (p‐phenylene‐ethynylene)‐alt‐poly(p‐phenylene‐vinylene) (PPE‐PPV) polymers (AnE‐PVs) bearing statistical distributions of various side chains. Primarily, the ratio of linear octyloxy and branched 2‐ethylhexyloxy side chains at the poly(p‐phenylene vinylene) (PPV) parts was varied, leading to the polymers stat, stat1, and stat2. Furthermore, polymers also containing asymmetric substituted PPV and poly(p‐phenylene ethynylene) units (bearing methoxy and 2‐ethylhexyloxy side chains) were prepared yielding stat3, stat4, and stat5. These materials exhibit a broad variation in their photovoltaic properties. It is once more shown that side chains and their distribution can crucially affect the photovoltaic device performance. The introduction of units with asymmetric substitution into these systems seems to be harmful for their utilization in photovoltaic applications. Organic field‐effect transistors were fabricated to investigate hole mobilities in these new materials. Large variance was observed, falling in the range of almost two orders of magnitude, indicating rather different π–π stacking behavior of the polymer backbones owing to side‐chain modifications. Moreover, a selection of the new polymeric systems was investigated regarding their potential for light‐emitting diode (LED) applications. Polymer LEDs using the polymers AnE‐PVstat, ‐stat3, ‐stat4, and ‐stat5, as the active layer showed turn‐on voltage of ~2 V and exhibited red light emission. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

17.
This article describes the synthesis and properties of the first poly(arylene‐vinylene)‐based sensitizers for application in dye‐sensitized solar cells (DSSC). The polymers were prepared by the Suzuki–Heck copolymerization of potassium vinyltrifluoroborate (PVTB) with a mixture of dibromoaryl comonomers designed to obtain macromolecules able to bind onto the photoelectrode by means of carboxyphenylene units. The copolymerization reactions were carried out in the presence of an excess of PVTB to lower the molecular weights of the polymers, which were obtained as soluble materials. The polymers poly[(9,9‐didodecyl‐2,7‐fluorenylene)‐vinylene‐co‐(carboxy‐2,5‐phenylene)‐vinylene] ( P1 ), poly[(9,9‐didodecyl‐2,7‐fluorenylene)‐vinylene‐co‐(carboxy‐2,5‐phenylene)‐vinylene‐co‐(4,7‐benzothiadiazolylene)‐vinylene] ( P2 ), and poly[(9,9‐didodecyl‐2,7‐fluorenylene)‐vinylene‐co‐(carboxy‐2,5‐phenylene)‐vinylene‐co‐2,5‐thienylene‐vinylene] ( P3 ) were used in DSSC devices, obtaining conversion efficiencies up to 0.88% ( P3 ). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

18.
Poly(2-methoxyphenylene vinylene) has been synthesized by a four step reaction sequence beginning with the bromination of 2,5-dimethylanisole and proceeding to the formation of an intermediate sulfonium salt precursor polymer. The infrared and UV-visible spectra of the PPV derivative asymmetrically substituted on the phenyl ring are presented. Films of poly(2-methoxyphenylene vinylene) can be doped with iodine to give a conductivity of 1 S cm?1. Films doped with AsF5 exhibited activated charge transport behavior with room temperature conductivities of about 100 S cm?1.  相似文献   

19.
Both fully conjugated polymer poly[2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylene vinylene‐alt‐9,10‐anthrylene vinylene] [poly(MEHPV‐AV)] and conjugated/nonconjugated block copolymers poly(alkanedioxy‐2‐methoxy‐1,4‐phenylene‐1,2‐ethenylene‐9,10‐anthrylene‐1,2‐ehthenylene‐3‐methoxy‐1,4‐phenylene)[poly(BFMPx‐AV), (x = 4, 8, and 12)] were synthesized by Horner–Emmons reaction utilizing potassium tert‐butoxide. Of these synthesized polymers poly(BFMP4‐AV) and poly(BFMP8‐AV), which has four and six methylene groups as solubility spacer in the main chain exhibited liquid crystalline to isotropic transition in addition to the two first order transitions. Light‐emitting diode (LED)s made from the organic solvent soluble poly(BFMP12‐AV) as emitting layer showed blue shift in the emission spectrum compared to the one made from fully conjugated poly(MEHPV‐AV). Although poly(BFMP12‐AV) had higher barrier to the electron injection from cathode than poly(MEHPV‐AV), the luminance efficiency of LED made from poly(BFMP12‐AV) was about 25 times higher than the one made from poly(MEHPV‐AV), which had fully conjugated structure. LEDs fabricated by both poly(BFMP12‐AV) and poly(MEHPV‐AV) exhibited Stoke's shift in the range of 155 to 168 nm from the absorption maximum due to the excimer formation between the ground and excited state anthracene groups. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3173–3180, 2000  相似文献   

20.
A soluble cyano‐substituted poly[(1,3‐phenylene vinylene)‐alt‐(1,4‐phenylene vinylene)] derivative ( 9 ) was synthesized and characterized. Comparison between 9 and its model compound ( 10 ) showed that the chromophore in 9 remained to be well defined as a result of a π‐conjugation interruption at adjacent m‐phenylene units. The attachment of a cyano substituent only at the β position of the vinylene allowed the maximum electronic impact of the cyano group on the optical properties of the poly(p‐phenylene vinylene) material. At a low temperature (?108 or ?198 °C), the vibronic structures of 9 and 10 were partially resolved. The absorption and emission spectra of a film of 9 were less temperature‐dependent than those of a film of 10 , indicating that the former had a lower tendency to aggregate. A light‐emitting diode (LED) based on 9 emitted yellow light (λmax ≈ 578 nm) with an external quantum efficiency of 0.03%. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3149–3158, 2003  相似文献   

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