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1.
设计并合成了一系列含手性和发光生色团侧基的聚(1-苯基-1-辛炔)衍生物{-[(C6H13)C=C(C6H4-p-CO2-R)]n-,R=[(1S)-endo]-(-)-冰片基(P3),(1R,2S,5R)-(-)-薄荷基(P4),-C6H4-p-(1R,2S,5R)-(-)-薄荷基(P5),2-萘基(P6),4-联苯基(P7)}.用WCl6-Ph4Sn作催化剂,成功地制备了这些具有中等产率和高分子量(Mw高达64000)的聚合物.聚合物的结构和性能通过NMR,TGA,UV,CD,PL和EL等分析方法进行了表征.所有聚合物都表现出良好的热稳定性,在N2保护条件下,其失重5%的温度在300~416℃之间.所有聚合物的带隙约为3.0eV.聚合物P4和P5表现出与聚合物链段螺旋性相对应的CD吸收.在UV辐照下,P3~P7的THF溶液均发射强烈蓝光,其最大发射波长位于485nm左右,量子效率均高于20%.聚合物薄膜发射与其溶液发射在相同的光谱区域,并表现出轻微的聚集诱导猝灭.制备了ITO/聚合物:PVK/BCP/Alq3/LiF/Al多层聚合物EL器件,其最大发射波长为487nm.随着侧基的改变,器件的最大亮度和外量子效率也随之发生变化,其中P6表现出最高的外量子效率(0.16%).EL器件均具有良好的光谱稳定性,其EL最大发射峰几乎不随外加电压的变化而改变.  相似文献   

2.
New acetylene monomers, 6-{[(1-naphthylethynyl-4-phenyl)carbonyl]oxy}-1-pheny-1-hexyne (1), 2, 5-diethynyl-thiophene (3), and 4,4'-diethynylbiphenyl(6) were synthesized. Homopolymerization of 1 and copolycyclotrimerizations of 3and 6 with 1-heptyne and 1-octyne have been achieved with WCl_6- and TaCl_5-Ph_4Sn catalysts, respectively, giving solublelinear disubstituted polyacetylene (2) and hyperbranched polyarylenes (5 and 8) with high molecular weights (up to 1.2×10~5) in high yields (up to 98%). The trictures and properties of the polymers are characterized and evaluated by IR, NMR,TGA, UV, photoluminescence (PL), and electroluminescence (EL) analyses. All the polymers possess high thermal stabilityand emit strong blue ligh upon photoexcitation. The intensity of the emitted light is greater than that of poly(1-phenyl-1-octyne), a well-known highly luminescent disubstituted polyacetylene. Little aggregation-induced red shift in the PL wasobserved in the thin films of the polymers. By constructing a multi-layer EL device, high EL quantum yield (0.18%) has beenachieved in 2, which are the best results for substituted polyacetylenes attainable so far.  相似文献   

3.
Thermally stable zinc(II) Schiff base polymers (decomposition temperature up to 461 degrees C; M(n)= 13580 to 20440) formed by self-assembly reactions of zinc(II) salts and salicylaldimine monomers exhibit blue to yellow PL with quantum yields up to 0.34 in DMF; PLEDs employing these polymers as emitters give green or orange EL with turn-on voltage at 5 and 6 V and maximum efficiency of 2.0 and 2.6 cd A(-1) respectively.  相似文献   

4.
Two novel triphenylamine-substituted poly(p-phenylenevinylene) derivatives, P1 and P2, have been successfully synthesized through the Witting-Horner reaction. The structures and properties of the monomers and the resulting polymers were characterized by using 1H NMR, FT-IR, GPC, TGA, UV-vis absorption spectroscopy, cyclic voltammetry (CV) and electroluminescence (EL) spectroscopy. The obtained polymers exhibited good thermal stability and high photoluminescence quantum yield (0.42-0.90). The polymer light-emitting diodes (PLEDs) with the configuration of ITO/PEDOT/polymers/Ca/Al were fabricated. The single-layer device based on P1 and P2 emitted stable blue and yellow light with the turn-on voltage of 4 and 6 V, respectively. The maximum luminance of 3003 cd/m2 at 10 V was obtained for device P2.  相似文献   

5.
Bipolar blue light-emitting polyfluorenes(PFSO-Cz) containing electron-deficient dibenzothiophene-S,S-dioxide(SO) and electron-rich carbazole(Cz) unit were synthesized. All the polymers show a high thermal stability with the decomposition temperatures over 400℃ and higher photoluminescence quantum yields. The highest occupied molecular orbital energy levels(EHOMO's) slightly enhance and the lowest unoccupied molecular orbital energy levels(ELUMO's) gently depress with the increase of Cz content in the polymers. PL spectra of the polymers display remarkable red shift and broadening with the increase of solvent polarities, indicating significant intramolecular charge transfer(ICT) effect in the polymers. Electroluminescence(EL) spectra of the polymers exhibit a broadening tendency with increasing the content of Cz unit in the polymers. The superior device performances were obtained with the maximum luminous efficiency(LE­max) of 5.2 cd/A, the maximum external quantum efficiency(EQEmax) of 4.8% and the Internationale de l'Eclairage(CIE)(x,y) coordinates of (0.16, 0.17) for PFSO15-Cz10 based on the single-layer device of ITO/PEDOT:PSS/EL/CsF/Al. The results indicate that the efficient bipolar blue light-emitting polyfluorenes are also constructed by Suzuki copolymerization using the monomers in common use.  相似文献   

6.
Novel ter(9,9-diarylfluorene)s were synthesized by a Suzuki-coupling reaction of 2-bromofluorene (1) and 2,7-fluorenediboronic ester derivatives (3) with high isolated yields (63-86%). The X-ray structure analysis of ter(9,9'-spirobifluorene) (4aa) revealed that the conjugated chromophore adopts a helical conformation. This conformation effectively releases the steric interaction between the fluorene moieties and prevents inter-chromophore interactions. The introduction of aryl groups at the C9 position of fluorene was highly beneficial to the thermal and morphological stability of these oligomers. These terfluorenes exhibit intense blue fluorescence with excellent quantum yields both in solution ( approximately 100%) and in solid state (66-90%), and possess interesting reversible redox properties. Highly efficient blue light-emitting OLED devices were fabricated using 4aa and 4cc as emitters as well as hole transporters. The devices exhibit low turn-on voltage ( approximately 3 V) and high EL external quantum efficiency (2.5-3%).  相似文献   

7.
New hyperbranched polyarylenes (HPAs) and linear polyacetylenes (LPAs) containing chromophoric moieties were synthesized in high yields (up to 97%) by coablt- and tantalum-catalyzed polycyclotrimerizations and tungsten-catalyzed metathesis polymerizations, respectively. The polymers possessed high molecular weights (Mw up to 113 000 Da) and were completely soluble in common organic solvents. The HPAs emitted strong UV light of 400 nm in high quantum yields (ΦF up to 0.98) and limited intense laser pulses, whose limiting threshold and signal suppress power were better than those of C60, a well-known optical limiter. The electroluminescence (EL) devices of the LPAs emitted blue light of ∼460 nm and exhibited maximun brightness, current efficiency, and external quantum efficiency of 1118 cd/m2, 1.53 cd/A, and 0.85%, respectively.  相似文献   

8.
A series of copolymers PCt‐co‐Poly(N‐vinylcarbazole) were synthesized through common radical polymerization, in which P‐Ct as a kind of mesogen‐jacketed liquid crystalline polymer was introduced, and the effects of copolymers composing variation on the optical properties of the polymers were studied. The structures and properties of the copolymers were characterized and evaluated by thermogravimetric (TGA), UV, photoluminescence (PL), cyclic voltammetry (CV), and electroluminescence (EL) analyses. All the polymers enjoy high thermal stability. PL peaks in the film show blue‐shift compared with in solutions and fluorescent quantum efficiency decreased with the N‐vinylcarbazole (nvk) content increasing, which supported the efficient energy transfer from nvk units to the oxadiazole units. CV revealed that, with the incorporation of nvk to the copolymer, these copolymers had high‐lying HOMO energy levels ranging from ?5.94 to ?6.09 eV. Single‐layer light‐emitting diodes (LEDs) with the configuration of ITO/PEDOT/PCt‐nvk/Mg:Ag/Ag were fabricated, which emit a blue light around 450 and 490 nm with a maximum luminance of 703 cd/m2. The device performance varies with the content of nvk and device configuration, with device configuration ( b ) and PCt‐nvk8 giving the best value of external quantum efficiency of 0.27%. We show here that by proper design copolymer structure and modification of device configuration can exhibit strong blue EL in higher external quantum efficiency. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1843–1851, 2008  相似文献   

9.
Biphenyl (Biph)-containing 1-phenyl-1-octynes and their polymers are synthesized, and the effects of functional bridge groups on the mesomorphic and optical properties of the polymers are studied. The nonmesomorphic disubstituted acetylene monomers (C6H13)C[triple bond]C(C6H4)O(CH2)12O-Biph-OC7H15 (1), (C6H13)C[triple bond]C(C6H4)O(CH2)11OOC-Biph-OC7H15 (2), and (C6H13)C[triple bond]C(C6H4)CO2(CH2)12OOC-Biph-OC7H15 (3) are prepared by multistep reaction routes and converted into their corresponding polymers P1-P3 by a WCl6-Ph4Sn catalyst. The structures and properties of the polymers are characterized and evaluated by NMR, TGA, DSC, POM, XRD, UV, and PL analyses. The mesogenic pendants have endowed the polymers with high thermal stability (> or =400 degrees C). While P1 exhibits no liquid crystallinity, P2 and P3 form enantiotropic S(A) phase with a monolayer structure. Upon photoexcitation, the polymers emit blue and blue-green lights of 460 and 480 nm, respectively, in THF with quantum efficiencies larger than 30%. UV irradiation of a thin film of P2 through a mask oxidizes and quenches the light emission of the exposed regions, generating a two-dimensional luminescent photoimage.  相似文献   

10.
Three new poly(fluorenevinylene) derivatives were synthesized, characterized, and used as emissive materials in light‐emitting diodes (LEDs). They were synthesized by Heck coupling of 9,9‐dihexyl‐2,7‐divinylfluorene with 2,7‐dibromo‐9,9‐dihexylfluorene, 2,3‐bis(4‐bromophenyl)quinoxaline, or 2,5‐bis(4‐bromophenyl)‐3,4‐diphenylthiophene to afford the polymers F , Q , and T , respectively. Polymers F and Q had medium number–average molecular weights (Mn ? 14,000) with relatively narrow polydispersity (1.3–1.6), while T was obtained as an oligomer (Mn ? 4000). All polymers were soluble in common organic solvents, such as tetrahydrofuran (THF), chloroform, dichloromethane, and toluene. They emitted blue‐greenish fluorescence light in dilute THF solution (444–491 nm), with photoluminescence (PL) quantum yields of 0.32–0.54, and in thin film (453–488 nm). LEDs with the configuration of ITO/PEDOT‐PSS/Polymer/Li:Al were fabricated and evaluated. The electroluminescence (EL) spectra of the Q and F polymers were very broad covering the blue–green–red region, whereas the spectrum of the polymer T was almost purely blue. The threshold electrical field for light emission of the devices was almost the same (?1.75 MV/cm). The external quantum efficiency of the devices of polymers Q and F was about 1.0 × 10?3%, whereas that of polymer T was ?3.0 × 10?5%. The fluorescence lifetime of polymers F and Q was significantly longer than that of the polymer T . © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4494–4507, 2006  相似文献   

11.
New hyperbranched poly(aryleneethynylene)s containing carbazole moieties are synthesized in high yields(up to 87%)by polycyclotrimerization of 3,6-bis(4-ethynylphenyl)-9-octylcarbazole and its copolymerization with 1-octyne catalyzed by CpCo(CO)_2 in THF.The structures and properties of the polymers are characterized and evaluated by IR,NMR, TGA,UV,photoluminescence,and cyclic voltammetry analyses.All the polymers are soluble in common organic solvents and show outstanding thermal stability(≥430℃).They graphitize in high yields(up to 79%)when pyrolyzed at 800℃. Upon photoexcitation,the polymers emit a strong deep blue light of ca.400 nm with quantum yields larger than 60%.  相似文献   

12.
New aromatic diyne monomers of 1,4‐diethynyl‐2,5‐(dihexyloxy)benzene ( 1 ), 1,6‐diethynyl‐2‐(hexyloxy)naphthalene ( 2 ), and 9,9‐bis(4‐ethynylphenyl)fluorene ( 3 ) are synthesized. Their homopolymerizations and copolymerizations with 1‐octyne ( 4 ) or phenylacetylene ( 5 ) are effected by TaBr5–Ph4Sn and CpCo(CO)2, giving soluble hyperbranched polyarylenes with high molecular weights (Mw up to ~ 2.9 × 105) in high yields (up to 99%). The structures and properties of the polymers are characterized and evaluated by IR, NMR, UV, PL, and TGA analysis. The polymers show excellent thermal stability (Td > 400 °C) and carbonize when pyrolyzed at 900 °C. Upon photoexcitation, the polymers emit deep blue light in the vicinity of ~400 nm with fluorescence quantum yields up to 92%. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4249–4263, 2007  相似文献   

13.
A novel series of poly(10‐hexyl‐phenothiazine‐S,S‐dioxide‐3,7‐diyl) and poly(9,9′‐dioctyl‐fluorene‐2,7‐diyl‐alt‐10‐hexyl‐3,7‐phenothiazine‐S,S‐dioxide) (PFPTZ‐SS) compounds were synthesized through Ni(0)‐mediated Yamamoto polymerization and Pd(II)‐catalyzed Suzuki polymerization. The synthesized polymers were characterized by 1H NMR spectroscopy and elemental analysis and showed higher glass transition temperatures than that of pristine polyfluorene. In terms of photoluminescence (PL), the PFPTZ‐SS compounds were highly fluorescent with bright blue emissions in the solid state. Light‐emitting devices were fabricated with these polymers in an indium tin oxide/poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate)/polymer/Ca/Al configuration. The electroluminescence (EL) of the copolymers differed from the PL characteristics: the EL device exhibited a redshifted greenish‐blue emission in contrast to the blue emission observed in the PL. Additionally, this unique phenothiazine‐S,S‐dioxide property, triggered by the introduction of an electron‐deficient SO2 unit into the electron‐rich phenothiazine, gave rise to improvements in the brightness, maximum luminescence intensity, and quantum efficiency of the EL devices fabricated with PFPTZ‐SS. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1236–1246, 2007  相似文献   

14.
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   

15.
3,6-二乙炔基-9-(三苯胺基)-咔唑、4,4′-二乙炔基-4″-(咔唑基)-三苯胺双炔和1-辛炔单炔在CpCo(CO)2-hν催化的条件下合成了新型超支化聚芳烃.所得的聚合物都溶于普通溶剂(甲苯、THF、氯仿、二氯甲烷等).在光激发的条件下,聚合物在428 nm左右发射蓝光,其荧光量子效率达到62%.所有超支化聚合物都表现出优异的热稳定性,它们的起始分解温度高达484℃.  相似文献   

16.
Two novel diketopyrrolopyrrole-based alternating copolymers, poly(2,7-(9,9-diethyl)-fluorenylvinylene-alt-2,5-bis(4′-octyloxyphe- nylmethyl)-3,6-bis(4-vinylenephenyl)pyrrolo[3,4-c]pyrrole-1,4-dione) (P1) and poly(1,4-(2,5-dioctyl- oxy)-phenylenevinylene-alt-2,5-bis(4′-octyloxyphenylmethyl)-3,6-bis(4-vinylenephenyl)pyrrolo[3,4-c]pyrrole-1,4-dione) (P2) were synthesized through Wittig polycondensation in good yields. P1 and P2 were characterized by NMR, FT-IR, UV-Vis, photoluminescence (PL) and electroluminescence (EL). EL devices with ITO/PEDOT/polymer/CsF/Al exhibited red-emitting light with the maximum EL wavelength at 620 nm and 682 nm. The results show that PL quantum yield of the polymers in thin film can be improved through N-alkylation of diketopyrrolopyrrole (DPP) with bulky substituent. EL performance of P2 was better than P1, which might be due to 1,4-dioctyloxybenzene of P2 enhancing the hole-transporting to make more charge balance. EL devices of P1 and P2 possessed low turn on voltage (2.4 V and 2.1 V, respectively), which was an advantage for PLED.  相似文献   

17.
Two new blue‐light‐emitting polyphosphazenes ( 1 and 2 ) containing carbazolyl groups as side chains were synthesized from a highly reactive macromolecular intermediate by a nucleophilic substitution reaction. Molecular structural characterization for the polymers was presented by 1H NMR, IR, and ultraviolet–visible spectra, gel permeation chromatography, and differential scanning calorimetry. The polymers exhibited excellent solubility in common organic solvents and were thermally stable. A fluorescence analysis of the two materials in tetrahydrofuran showed a strong blue light emitting. The quantum yields of the polyphosphazenes were 0.55 for 1 and 0.64 for 2 , relative to quinoline (in 0.1 N H2SO4). An electroluminescent diode was fabricated, and a bright blue light was observed; the maximum external quantum efficiency was about 0.026% at an applied forward voltage of 23 V. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3428–3433, 2001  相似文献   

18.
Deep blue emitting copolymers were synthesized by uniting the Eumelanin‐inspired indole core with fluorene and carbazole units via Suzuki polymerization. The resulting polymers, PIF and PIC, showed deep blue emission in the range of 416–418 nm and quantum yields of 0.39–0.60. Both polymers exhibited an intense and stable electrogenerated chemiluminescence. Interestingly, deep HOMO levels of −5.71 and −5.61 eV were observed for PIF and PIC, respectively. Solution processed polymer light emitting diodes (PLEDs) were fabricated using the PIF as a guest. PLEDs emitted deep blue light at 418 nm, with the luminous efficiency peaking at 1 Cd/A, given that the photopic response at that wavelength is 0.0151. The electroluminescence of PIF displayed a Commission Internationale de l'Eclairage coordinates of (0.16, 0.07) with a maximum external quantum efficiency of 1.1%. Hence, these materials prove to be promising candidates for the fabrication of deep blue PLEDs. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 125–131  相似文献   

19.
Whereas chain aggregation commonly quenches light emission of conjugated polymers, we here report a phenomenon of aggregation-induced emission enhancement (AIEE): luminescence of polyacetylenes is dramatically boosted by aggregate formation. Upon photoexcitation, poly(1-phenyl-1-alkyne)s and poly(diphenylacetylene)s emit blue and green lights, respectively, in dilute THF solutions. The polymers become more emissive when their chains are induced to aggregate by adding water into their THF solutions. The polymer emissions are also enhanced by increasing concentration and decreasing temperature. Lifetime measurements reveal that the excited species of the polymers become longer-lived in the aggregates. Conformational simulations suggest that the polymer chains contain n=3 repeat units that facilitate the formation of intramolecular excimers. The AIEE effects of the polymers are rationalized to be caused by the restrictions of their intramolecular rotations by the aggregate formation.  相似文献   

20.
采用缩聚反应,通过将深蓝光荧光团(五联芴)和橙光荧光团(4-芴基-7-(4-二苯胺基-苯基)-2,1,3-苯并噻二唑)分别链接在聚芳醚的侧链上,合成了一种双色白光电致发光聚芳醚P1,接着将一种高效浅蓝光荧光团(2,7-二(9-乙基-咔唑乙烯基)芴)引入到了P1的侧链上,得到了聚芳醚P2和P3.系统研究了这些聚芳醚材料的溶解性、热稳定性、电化学性能、光物理性能和电致发光性能等.结果表明,所有聚芳醚都具有良好的溶解性与热稳定性;薄膜态时存在明显的由深蓝光荧光团到浅蓝光荧光团及橙光荧光团的能量转移;退火前后的薄膜光致发光光谱基本一致,表明具有优秀的光谱稳定性.基于这些聚芳醚的单层电致发光器件(ITO/PEDOT:PSS/高分子/Ca/Al),利用部分能量转移和电荷俘获作用,可以实现近白光发射.器件的最大电流效率可以达到7.96 cd/A,最大亮度为9950 cd/m2,色坐标为(0.33,0.44).  相似文献   

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