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1.
利用侧链带酰氯基的聚硅氧烷与取代偶氮苯酚进行大分子反应,合成了6种以偶氮苯氧羰基为侧链的聚硅氧烷Ⅲa-f;将其中的Ⅲa-c进行氧化,得到3种以氧化偶氮苯氧羰基为侧链的聚硅氧烷Ⅳa-c聚合物结构通过核磁共振、红外光谱和元素分析表征,利用偏光显微镜和差热分析仪研究了聚合物的相行为.讨论了苯环上取代基和液晶基元的中心桥键对聚合物液晶性能的影响.  相似文献   

2.
芴衍生物的合成、结构与蓝色(λmax=418nm)双光子荧光   总被引:2,自引:1,他引:2  
分别以二苯胺和咔唑为端基,以芴为共轭桥, 合成了两个对称型芴衍生物:2,7-二-(N,N-二苯胺基)-9,9-二乙基芴[2,7-bis(N,N-diphenylamino)-9,9-diethyl-fluorene,简称DPDEF]和2,7-二咔唑基-9,9-二乙基芴(2,7-dicarbazol-9'-yl-9,9-diethyl-fluorene,简称DCDEF).用四圆X射线衍射方法测定了其晶体结构.DPDEF单晶属于单斜晶系,C2/c空间群.晶胞参数:a=2.8649(4) nm, b=0.85111(9) nm, c=2.7012(4) nm, β=100.982(11)º, V=6.4657(14) nm3, Z=8, Dc=1.144 g·cm-3, R=0.0581. DCDEF单晶属于单斜晶系,P21/c空间群.晶胞参数:a=0.92794(12) nm, b=0.88561(9) nm, c=3.7236(4) nm, β=96.914(9)º, V=3.0378(6) nm3, Z=4, Dc=1.208 g*cm-3, R=0.0652.晶体中DPDEF和DCDEF的芴桥具有很好的平面性,构成芴桥的两个苯环平面之间的夹角分别仅为3.0º和5.8º.在波长为730 nm的飞秒脉冲激光激发下,化合物DPDEF在THF中发出强的蓝色双光子上转换荧光(λmax=418 nm),测得双光子吸收截面为15 GM.  相似文献   

3.
Two novel spiro‐configured ter(arylene‐ethynylene) derivatives, TSF‐Cz and TSF‐F , have been designed and synthesized using spiro(fluorene‐9,9′‐xanthene) (SFX) as building blocks, introducing a hole‐transporting carbazole and a fluorene chromophore as the peripheral functional group into the backbone through an oxygen atom. The two well‐defined oligomers possess good solubility, film‐forming quality, and high Tg's at 140 and 126 °C, respectively. In addition, these oligomers exhibit blue photoluminescence (PL) emission both in solution and solid states. The double‐layered devices fabricated using the two materials as the emitter show a sky‐blue emission with a brightness and a current efficiency of 7 613 cd · m−2 and 1.11 cd · A−1 for TSF‐Cz , and 1 507 cd · m−2 and 0.36 cd · A−1 for TSF‐F , respectively.

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4.
Phenylacetylene dendrimers 9 – 11 containing fluorene as the core with a larger HOMO‐LUMO energy gap were synthesized and characterized. Their structure and properties were studied by UV, FL, 1H NMR, MS etc. These novel phenylacetylene dendrimers exhibit unique photophysical properties. They exist a new absorption band around 340 nm whose molar coefficient decreases with increasing generation. The band‐gaps of 9 – 11 are 3.54, 3.43 and 3.02 respectively. The fluorescence quantum yield of 10 is as high as 0.61.  相似文献   

5.
主链含酞和芴结构的无定形聚芳醚酮的合成   总被引:1,自引:0,他引:1  
通过共聚改性在酚酞聚芳醚酮(PEK-C)的主链上引入含芴侧基,制备了一系列主链含酞和芴结构的线性高分子量无定形聚芳醚酮无规共聚物.通过傅里叶红外光谱(FTIR)、核磁共振谱(1H,13C NMR)等手段确定了共聚物结构.凝胶渗透色谱(GPC)数据表明,共聚物的Mn>6.0×104,Mw>1.0×105,PDI(Mw/Mn)范围在1.6~1.7之间.X射线衍射(XRD)数据表明共聚物系无定形结构,差示扫描量热法(DSC)和热重分析(TGA)测试表明聚合物具有良好的耐热性;初始热分解温度高于467℃;700℃时残炭率大于58.9%;共聚物呈现单一的玻璃化转变温度(Tg>243℃).当酚酞与双酚芴摩尔比在3∶7~5∶5范围时,共聚物的弹性模量和断裂伸长率显著提高,可分别达到3.1 GPa和58%,是酚酞聚芳醚酮的1.4倍和8.3倍.这类含酞和芴侧基的无定形聚芳醚酮保持了在氯仿、二氯甲烷、四氢呋喃(THF)和甲基吡咯烷酮(NMP)等极性非质子溶剂中良好的溶解性能,并显著提高了聚合物的力学性能和热性能.  相似文献   

6.
随着光固化技术的发展,当前广泛使用的自由基光固化逐渐显示出一些弊端,与自由基光固化相比,阳离子光固化逐渐显示出其固有的优势,如体积收缩小、附着力强、无氧阻聚等。活性稀释剂作为阳离子光固化配方中的重要组成,对配方的固化及最终产品的机械物理性能具有显著影响,因此开发可快速固化的活性稀释剂具有重要的意义。本文介绍了阳离子活性稀释剂的作用原理及特点,并对其发展前景和方向进行了展望。  相似文献   

7.
A convergent synthetic method for the synthesis of fluorene derivatives has been developed by devising a rhodium-catalyzed stitching reaction/alkene isomerization sequence. The reactions proceed smoothly under mild conditions for a variety of substrate combinations, and extended π-conjugation systems are also readily accessible by utilizing this synthetic method. Optical properties of the obtained fluorene derivatives have also been examined.  相似文献   

8.
含芴、蒽螺环结构电致发光材料的研究进展   总被引:1,自引:0,他引:1  
螺环芳香类化合物具有大的共轭体系和较好的刚性共面性, 而且玻璃化温度高, 热稳定性好(熔点大于300 ℃), 制作电致发光(EL)器件工艺简单, 不需要复杂的设备, 因而有可能降低器件制作成本, 特别是易于制备大面积器件. 对近年来含芴、蒽螺环结构发光材料的研究进展进行了总结, 重点介绍了含有双螺、单螺结构的有机电致发光材料的结构和特性, 给出了部分有机化合物的合成方法. 对含有硅元素的螺环化合物发光材料进行了简单介绍.  相似文献   

9.
Amine-terminated and maleimide-terminated oligomers of molecular weight 1200–1800 based on 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl and 3,3′,4,4′-biphenylenetetracarboxylic dianhydride were synthesized and characterized for lyotropic liquid crystalline behavior. Several different synthetic procedures were evaluated and a one-step procedure in m-cresol was found to be the most effective for producing fully imidized materials. Lyotropic behavior was observed only for the as-prepared solutions in m-cresol and in dilutions of this solution. Oligomer thermal stability was excellent, onsets of decomposition were in excess of 550°C. © 1996 John Wiley & Sons, Inc.  相似文献   

10.
闫皙  李效军 《应用化学》2014,31(5):524-528
以聚甲醛为羟甲基化试剂,研究了碱的种类、反应温度和反应时间等因素对芴与聚甲醛发生羟甲基化反应产物类型的影响。 结果表明,提高碱的强度有利于生成9,9-双羟甲基芴,升高温度和延长反应时间则有利于生成9,9′-亚甲基双芴。 通过控制反应条件,有可能优先生成9-芴甲醇或9,9-双羟甲基芴或联产这2个化合物。  相似文献   

11.
The title compound, C37H42, is a new mesogenic compound containing the fluorene moiety. It exhibits enantiotropic nematic liquid crystalline behaviour with melting at 125 °C and isotropization at 175 °C. The crystallographically independent unit contains two molecules oriented face‐to‐edge with respect to each other. The two molecules have nearly the same conformation of the bis‐phenyl fluorene moiety. The molecular packing in the crystal phase is nematic‐like.  相似文献   

12.
A series of 3,7‐bis(9,9‐di‐n‐hexylfluoren‐2‐yl)‐N‐arylphenothiazine‐S,S‐dioxide trimers and (9,9‐di‐n‐octylfluorene‐2,7‐diyl‐co‐N‐arylphenothiazine‐S,S‐dioxide) co‐polymers, with varying ratios of phenothiazine‐S,S‐dioxide units, have been prepared in good yields by palladium‐catalyzed cross‐coupling reactions. The materials are deep blue emitters and show no solvatochromism or evidence for an intramolecular charge‐transfer state. The photoluminescence quantum yields of the trimers are ?PL 15–30% in solution and 14–25% in films. The polymers demonstrated very high values in solution (?PL 74–84%) and ?PL values in films of 28–47%. The estimated HOMO energy levels are between ?5.64 and ?5.62 eV for the polymers with 15% incorporation of the phenothiazine‐S,S‐dioxide units. An analogous N‐arylphenothiazine co‐polymer shows significantly red shifted absorption and emission. Solution electrochemical data and density functional theory calculations are also presented. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

13.
以4,4-(9-芴)二苯酚(BHPF)和碳酸二苯酯(DPC)为原料,采用熔融酯交换法合成了4,4-(9-芴)二苯酚型聚碳酸酯(BHPF-PC).红外光谱、核磁共振碳谱及氢谱测试结果证实了所得聚合物的化学结构.采用了四苯基膦苯酚盐(C_(30)H_(25)OP)等2种季磷盐以及3种碱性无机盐催化剂作为合成聚碳酸酯的催化剂,结果四苯基膦苯酚盐的催化效果最好.分析了DPC/BHPF初始摩尔比对BHPF-PC的影响规律,随着DPC/BHPF初始摩尔比的增加,BHPF-PC的分子量呈现先增加后降低的趋势.进一步研究了聚合工艺包括缩聚时间和缩聚温度对BHPF-PC的影响,结果表明BHPF-PC分子量达到最大值所需要的时间随DPC/BHPF初始摩尔比的增加而增加.初始摩尔比为1.1∶1的DPC和BHPF,在1×10~(-5)mol/mol(BHPF)的四苯基膦苯酚盐催化作用下,于330℃缩聚150 min可以获得分子量最大的BHPF-PC.最后研究了BHPF-PC的耐高温性能和光学性能,其Tg达到了275℃,空气中失重率为5%时的分解温度T5%为440℃,同时透光率达到了88.1%,表明BHPFPC是一种具有优异耐高温性能的高光学透明材料.  相似文献   

14.
The synthesis and optical properties of polymers bearing the repeating unit of terfluorene and various organosilicon groups were investigated. Polymers with high molecular weight and good solubility could be obtained by Suzuki coupling polymerization from silylene‐containing fluorene‐based dibromo monomers and 9,9‐dihexylfluorene‐2,7‐bis(trimethyleneborate). From UV spectra of polymers bearing acyclic silylene bridge, the organosilicon units not only interrupted a π‐conjugation but also contributed to an electronic communication between connected fluorenes. The emission maximum wavelengths (ca. 400 nm) blue‐shifted when compared with that of polyfluorene (418 nm) and the fluorescence quantum yields were considerably high (>0.82) in the CHCl3 solution. On the other hand, rather broad emission was observed at 480 nm and the fluorescence quantum yield was quite low (0.004) in the solution‐state PL spectrum of tetraphenylsilole‐containing polymer. The polymer emitted visible green light in the spin‐coated film. The fluorescence peak intensity at 486 nm gradually decreased when the film was illuminated with the UV light of 359 nm in air. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4786–4794, 2007  相似文献   

15.
耐热芴型环氧树脂的非等温固化动力学   总被引:3,自引:0,他引:3  
合成了9,9’-二[4-(2,3环氧丙氧基)苯基]芴,并以4,4’-二氨基二苯砜胺为固化剂,用非等温DSC法研究了其固化动力学,用Flynn-Wall-Ozawa法和Friedman法确定了固化动力学参数,用动力学模拟推测了固化机理函数,并用TGA法对等温固化树脂的耐热性进行了表征。结果表明:双酚芴环氧固化反应的表观活化能约63.86 kJ/mol,扩散因子为3.80×104s-1,反应级数为1.57;固化反应为枝状成核的自催化反应;等温固化后的环氧树脂于400℃开始分解,700℃时残碳率为41.73%。  相似文献   

16.
This work reports on the synthesis of three acid oligosiloxane‐urethane dimethacrylates and their use to obtain hybrid nanocomposite films, in which the presynthesized silver nanoparticles (NPs) were incorporated before photopolymerization, or produced via in situ photoreduction of the silver nitrate (AgNO3) precursor into the formulation, without any conventional reducing agent. All samples were characterized by 1H NMR, FT‐infrared and UV spectroscopies, photodifferential scanning calorimetry (photo‐DSC), transmission electron microscopy (TEM), and energy‐dispersive X‐ray (EDX) analysis. Fourier transformed infrared spectroscopy and photo‐DSC results showed that dimethacrylates having hydrophilic segment of poly(ethylene oxide) type in structure are more reactive than the acid oligosiloxane dimethacrylate. When another urethane dimethacrylate is taken as a comonomer, the photopolymerization rate (0.112–0.132 s?1) and the degree of conversion (82–93%) significantly increased. Experimental evidence of the existence of nanosilver into the polymer matrix generated upon UV irradiation has been supported by UV spectroscopy, EDX and TEM analysis, the last allowing a visualization of the formation of silver NPs with size between 2 and 15 nm. Mechanical parameters and wettability of the photocrosslinked films are also discussed in the prospect of further potential applications in the biomedical field. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

17.
芴类化合物的研究新进展   总被引:4,自引:0,他引:4  
芴及其衍生物是一类重要的具有刚性平面联苯结构的化合物,分子内含有较大的共轭体系,这种特殊的刚性稠环结构使芴类化合物表现出许多独特的光电性能及生物活性,在光电材料、医药等多领域具有潜在的广泛应用.更为重要的是芴类化合物易于进行结构修饰,在芴环上可方便地引入各种功能基,芴类衍生物的合成及其开拓芴类化合物潜在的新用途,成为近些年来十分活跃的研究领域,且发展迅速.结合自己的工作,参考国内外文献,全面综述了芴类化合物在有机电致发光材料、双光子吸收材料、光致变色材料、太阳能电池材料和生物医药等领域的研究与开发新进展,并对其发展趋势作了展望.  相似文献   

18.
《Analytical letters》2012,45(18):3386-3396
Abstract

The applicability of nonprotected room-temperature phosphorescence (NP-RTP) in real samples is demonstrated in this work. In this methodology only two reagents, potassium iodide and sodium sulfite, were used to obtain the phosphorescent signals. Synchronous phosphorimetry was used to enhance sensitivity. Analyses of dibenzofuran, acenaphthene, and fluorene were carried out in a sample of impure fluorene.  相似文献   

19.
Difunctional acrylates and methacrylate monomers have been made which are high order smectic liquid crystal (or crystalline) at room temperature. This report discusses materials with the following structure: F–S–M–S–F, where F is a functional group, acrylate or methacrylate (A or M); S is a spacer (CH2)n(n), and M is a mesogen—in this case 4,4′-dioxybiphenyl (B). They are codified as BnA or BnM where n is the number of methylenes in the spacer. High conversion with high Tg can be obtained when polymerizing in the smectic state because the reactive end groups are concentrated in a small volume and can react well with little or no diffusion. B2A, B3A, B6A, B11A, and B3M were polymerized in the smectic state and compared to polymers made at temperatures where the monomers were isotropic. High conversion was obtained below final Tg—even then, probably because the polymers were ordered. All the polymers were studied by WAXD and dynamic mechanical spectroscopy. Solid-state NMR on B3A showed that there was very high conversion of the double bonds at all temperatures. B3A photopolymerized in the smectic state (60–76°C) produced a crystalline polymer with Tg = 185°C (1 Hz). When photopolymerized at 85°C, above the isotropization temperature (Ti), a poorly organized polymer was obtained with a Tg of 155°C (1 Hz). Monomers with an odd number of methylene groups as spacers were crystalline after polymerization. With an even number of methylene groups, they lost most of their crystallinity on polymerization below Ti, but retained a low order smectic structure. Similar structures were obtained with all the monomers when they were polymerized above Ti. There was little effect of polymerization temperature on Tg when the spacers had an even number of methylene groups. © 1993 John Wiley & Sons, Inc.  相似文献   

20.
本文采取偏振-导数-同步扫描联用技术同时测定痕量的芴、苊、蒽和多环芳烃。实验结果表明,多种荧光分析技术联用可以弥补单独应用其中一种或两种技术的不足,扬长避短,大大改善此类化合物的检测限。该方法同时测定上述四种组份,检测限依次为0.089、2.4、0.045、0.0096 ng/mL,相对标准偏差不大于 5%。  相似文献   

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