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1.
树枝形聚合物是一类围绕着中心核,外围链段和官能团呈指数增长的支化高分子.合成方法的发展使发色团可被精确地置于树枝形聚合物的核心、外围甚至支化节点处.树枝形聚合物的特殊结构使其作为模拟光捕获体系被广泛研究.光诱导电子转移和能量传递是光合作用中的重要过程,研究树枝形聚合物体系中的电子转移和能量传递对未来树枝形聚合物在光电器件中的应用有着重要意义.本文综述了近年来光捕获树枝形聚合物体系的研究进展,并重点介绍光捕获树枝形聚合物体系中的能量传递和电子转移过程研究.  相似文献   

2.
含光功能基团聚合物LB膜的研究进展   总被引:4,自引:0,他引:4  
徐志康  徐又一 《高分子通报》1995,(2):112-116,98
本文在简要介绍含光功能基团聚合物LB膜之后,详细回顾了功能化LB膜体系光物理过程的研究,总结了含非线性光学基团聚合物LB膜的研究现状。最后,简要介绍了它们的应用前景。  相似文献   

3.
将一种含具有聚集诱导发光性能(AIE)的四苯乙烯的2-脲基-4[1H]-嘧啶酮衍生物(TPE-bis UPy)在氯仿中通过四重氢键作用组装形成的超分子聚合物,再以十六烷基三甲基溴化铵(CTAB)为表面活性剂利用微乳法制备了基于超分子聚合物的纳米球.这种纳米球的形貌通过SEM进行了表征,具有规整的形貌与尺寸.相比在溶液里,该超分子聚合物纳米球的荧光显著增强.通过改变单体的浓度得到了3种不同粒径的超分子聚合物纳米球,DLS表征其粒径分别为46、66和91 nm.将这3种不同粒径的TPE-bis UPy超分子聚合物纳米小球与带负电的曙红(EY)进行组装,由于静电相互作用曙红吸附在纳米球表面,拉近了TPE-bis UPy和曙红之间的距离,使得在组装体内TPE-bis UPy可以有效地将激发能传递给曙红分子,该体系的发光颜色从蓝色荧光变为黄绿色荧光,其能量传递效率分别为62%、55%和39%,洗去表面活性剂CTAB后静电作用减弱,能量传递效率显著降低,分别为46%、36%和33%.研究表明,TPE-bis UPy超分子聚合物纳米小球与曙红的组装体系内,静电作用越强能量传递效率越高;超分子聚合物纳米球粒径越小,能量传递效率越高;并且通过这种组装可以调控体系的发光颜色,能量传递也可以通过体系的发光颜色变化观察到.  相似文献   

4.
李鹏  曾毅  陈金平  李迎迎  李嫕 《化学学报》2012,70(15):1611-1616
设计合成了0~4代外围修饰激发态分子内质子转移(ESIPT)发色团的聚酰胺-胺树枝形聚合物G0~G4,化合物结构经过IR,1H NMR,13C NMR和MS表征.稳态光谱研究表明,树枝形聚合物在四氢呋喃溶液中形成了聚集体,发色团酮式发光随着化合物代数增大呈先增加后减小的变化.质子化树枝形聚合物G1-H~G4-H能溶于水,并在水中形成20 nm左右的聚集体,发色团在聚集体疏水区中构象受限,仅发射酮式发光,并且发光强度受树枝形聚合物分子大小的影响.  相似文献   

5.
设计合成了1 3代芳醚骨架树枝形聚合物修饰的双8 羟基喹啉衍生物.对这些化合物在不同溶剂中的荧光光谱研究表明,随着代数的增加,目标树枝形聚合物的荧光量子产率增大,树枝形聚合物对核心发色团具有一定的隔离作用,并且目标分子内可以发生从骨架向核心发色团的能量传递.  相似文献   

6.
水溶性共轭聚合物由于具有优异的光学性能,如强大的光捕获能力和独特的分子线效应,在化学、生物和医疗领域都有良好的应用前景。共轭聚合物受光激发后,所产生的激子可以沿着长程共轭的π骨架自由迁移,在分子骨架的任何位点都可以转移给能量受体,从而实现高效的能量传递。因此,水溶性共轭聚合物适合于构建各种能量传递体系,从而实现荧光信号放大、多色发光、活性氧产生效率提高等光学性能的优化。本文简述了基于水溶性共轭聚合物构建能量转移体系的原理和方法,总结了其在生物传感、生物成像、光动力杀菌和光动力抗癌等领域的应用,最后对水溶性共轭聚合物存在的主要问题以及未来的发展方向进行了分析和展望。  相似文献   

7.
构筑和发展新型光功能树枝形聚合物是当前研究热点之一. 聚集诱导发光(Aggregation Induced Emission. AIE)类化合物以其高固态发光量子产率和广阔的应用前景引起研究者的极大关注, 分子内旋转受限降低了非辐射失活被认为是AIE高固态发光量子产率的主要原因. 在树枝形聚合物的外围修饰聚集诱导发光基团, 改善树枝形聚合物的发光性能, 通过外界环境改变树枝形聚合物分子构象, 实现对功能化树枝形聚合物体系发光的调控, 对扩展光功能树枝形聚合物在发光材料以及光捕获体系中的应用有重要意义.  相似文献   

8.
曾毅  李迎迎  袁钊  李嫕 《化学学报》2009,67(23):2714-2720
合成了外围修饰有萘基团的0~3代聚酰胺-胺树枝形聚合物GnN (n=0~3), 化合物通过了IR, 1H NMR, 13C NMR和MALDI TOF的表征. 稳态光物理研究表明, 甲醇溶液中GnN外围萘基团与骨架胺之间发生电子转移过程, 形成最大发射峰在450 nm的激基复合物, 萘的荧光被明显猝灭; 当GnN骨架被质子化, 分子内光致电子转移过程和萘与骨架胺基间激基复合物的形成被抑制, 萘单体荧光发射大大增强; 由于质子化后树枝形聚合物骨架趋于伸展构象, 外围萘基团间相互作用增强, 部分形成最大发射峰在400 nm的激基缔合物.  相似文献   

9.
共轭聚合物发光和光伏材料研究进展   总被引:5,自引:1,他引:4  
聚合物光电功能材料与器件因其广阔的应用前景,1990年以年来吸引了世界各国学术界的广泛关注和兴趣.聚合物光电子器件主要包括聚合物电致发光二极管、聚合物场效应晶体管和聚合物太阳能电池等,其使用的关键材料是共轭聚合物光电子材料,包括共轭聚合物发光材料、场效应晶体管材料和光伏材料等.本文主要对共轭聚合物电致发光材料和光伏材料的研究进展进行综述,介绍了这些聚合物材料的种类、结构和性质以及在聚合物电致发光器件和聚合物太阳能电池中的应用.并讨论了当前共轭聚合物光电子材料中的关键科学问题和今后的发展方向.  相似文献   

10.
本文针对近五年来光功能稀土/无机/有机聚合物杂化材料的最新进展进行了评述,其重点着眼于高分子化合物作为构筑基元的发光稀土杂化材料体系的化学键组装.内容主要涉及稀土有机高分子杂化材料、配位键构筑的稀土/无机/有机高分子杂化材料、共价键构筑的稀土/无机/有机高分子杂化材料、自由基聚合构筑的稀土/无机/有机高分子杂化材料几个重要方面.主要结合我们自己的近期研究工作,通过系统总结来展现该领域的研究现状并提出未来展望.  相似文献   

11.
In the present study, photophysical properties of fluorescent poly(oxyethylene phosphate) tris(β-diketonate) europium (III) complexes have been studied by means of stationary and time-resolved fluorescence spectroscopy (in ethanol at room temperature). The luminescent quantum yields and efficiency for the energy transfer from β-diketonate ligands to Eu(III) ion have been determined for the studied complexes by using diffusion-enhanced fluorescence resonance energy transfer. Obtained results show effect of the polymer ligands upon photophysical properties of the complexes and a relation has been established with length of the oxyethylene spacer between two phosphonate groups. The Förster radiuses of the synthesized compounds with SulfoRhodamine 101 as acceptor have been calculated. Measured distances between molecules of the donors and acceptor at identical acceptor/donor molar ratios have been illustrated the difference in structure of the ternary and polymer complexes in solution even at low concentration.  相似文献   

12.
简要介绍了2005年度我国内地学者在高分子主要前沿领域基础研究的进展,涉及的领域主要包括特殊构筑高分子的合成、高分子结构表征、光电功能高分子、高分子自组装与超分子聚合物、高分子微纳结构与纳米复合体系、类细胞膜融合分裂的实时观测和生物医用高分子等。  相似文献   

13.
碳笼烯(C60)在高分子领域中的研究进展   总被引:3,自引:0,他引:3  
综述了碳笼烯(C60)在高分子领域中的研究进展,包括碳笼烯的高分子化、与聚合物形成电荷转移复合物以及作为催化聚合反应的催化剂。  相似文献   

14.
In the present work the hydrophobic β-cyclodextrin (β-CD) polymers have been used as macrocyclic ion carriers for separation of Pb(II), Zn(II), and Cu(II) ions from dilute aqueous solutions by transport across polymer inclusion membranes. The β-CD polymers were prepared by cross-linking of β-CD with 2-(1-docosenyl)-succinic anhydride derivatives in anhydrous N,N-dimethylformamide in the presence of NaH. The metal ions were transported from aqueous solutions containing heavy metal ions through plasticizer triacetate membranes with dimer and polymer β-CD derivatives into distilled water. The selectivity of lead(II) over other metal ions in the transport through polymer inclusion membrane was very high, especially for dimer cyclodextrin carrier. In the case of competitive transport of Pb(II), Cu(II), and Zn(II) ions through plasticized immobilized membranes the selectivity of process is controlled via formation of ion pairs of β-CD hydroxyl groups with metal cations. The polymer and dimer of β-CD linked by 2-(1-docosenyl)-derivative used as ionic carriers for competitive transport of metal ions show preferential selectivity order: Pb(II)  Cu(II) > Zn(II). Application of ion carriers mixtures (β-CD polymers and palmitic acid) causes the increase of Pb(II) maximal removal from dilute aqueous solution. The weight-average molecular weight (MW) and the chemical structure of the β-CD polymers were determined using high-performance size exclusion chromatography with refractive index detector, and 1H NMR spectroscopy.  相似文献   

15.
近年来,表面引发聚合制备聚合物刷,由于其能控制无机物表面性能,在材料科学方面有广泛的应用前景.在制备聚合物刷的一系列聚合方法中,“活性”/可控自由基聚合,尤其是原子转移自由基聚合(Atom Transfer Radical Polymerization,ATRP)得到广泛使用.它可获得分子量分布较窄的结构规整的聚合物,可将一些功能性的单体引入聚合物体系获得功能聚合物,  相似文献   

16.
Polymer science entails the structural study at multi-levels from nano-to micro-and mesoscale,which is highly important to transfer or even amplify the molecular information to macroscopic materials.Multiple polymer structural transitions from lower-order to higher-order superstructures are normally involved to achieve selective,efficient and sophisticated functions.Therefore,in-situ visualization of these processes is highly important,not only for fundamental understanding the structural evolution,but also for the optimization of the process flow during the materials processing.Fluorescence imaging based on aggregation-induced emission(AIE)provides an ideal tool that offers a simple,accurate,and easy-readable method to fulfill the above requirements.Owing to the twisted propeller-like structure of AIE luminogens(AIEgens),they show high fluorescence sensitivity to the surrounding microenvironment(e.g.,viscosity,rigidity,and polarity)through intramolecular motions.In this short review,we summarize the recent applications of AIEgens to serve as“built-in”sensors to analyze the process of polymerization,microphase separation,glass/vitrification transition,polymer solvation,crystallization,etc.The perspective on the future application of AIE technology in polymer engineering,especially fiber materials,is also discussed.  相似文献   

17.
原子转移自由基聚合反应(ATRP)是实现活性聚合,获得可控聚合物的一种有效途径。通过表面引发原子转移自由基聚合,在材料表面合成聚合物刷,是改变材料表面特征的有效方法。本文综述了表面引发原子转移自由基聚合合成聚合物刷及其最新进展。  相似文献   

18.
Atmospheric pressure photoionization (APPI) followed by mass spectrometric detection was used to ionize a variety of polymers: polyethylene glycol, polymethyl methacrylate, polystyrene, and polysiloxane. In most cases, whatever the polymer or the solvent used (dichloromethane, tetrahydrofuran, hexane, acetone or toluene), only negative ion mode produced intact ions such as chlorinated adducts, with no or few fragmentations, in contrast to the positive ion mode that frequently led to important in-source fragmentations. In addition, it was shown that optimal detection of polymer distributions require a fine tuning of other source parameters such as temperature and ion transfer voltage. Series of mass spectra were recorded in the negative mode, in various solvents (dichloromethane, tetrahydrofuran, hexane, toluene, and acetone), by varying the photon energy from 8 eV up to 10.6 eV using synchrotron radiation. To these solvents, addition of a classical APPI dopant (toluene or acetone) was not necessary. Courtesy of the synchrotron radiation, it was demonstrated that the photon energy required for an efficient ionization of the polymer was correlated to the ionization energy of the solvent. As commercial APPI sources typically use krypton lamps with energy fixed at 10 eV and 10.6 eV, the study of the ionization of polymers over a wavelength range allowed to confirm and refine the previously proposed ionization mechanisms. Moreover, the APPI source can efficiently be used as an interface between size exclusion chromatography or reverse phase liquid chromatography and MS for the study of synthetic oligomers. However, the photoionization at fixed wavelength of polymer standards with different molecular weights showed that it was difficult to obtain intact ionized oligomers with molecular weights above a few thousands.  相似文献   

19.
The effect of oxygen plasma treatment on the surface properties of tin-doped indium oxide (ITO) substrates and the changes in surface properties of treated ITO substrates with ageing time were investigated by X-ray photoelectron spectroscopy (XPS), contact angle and surface free energy measurements. Experimental results show that oxygen plasma treatment increases the oxygen concentration, decreases the carbon concentration, and enhances the surface free energy and polarity, and thereby improves the surface properties of ITO substrates. However, the improved ITO surface properties tended to decay and the surface free energy decreased, with ageing time. In addition, the ageing effect of treated ITO substrates on the performance of polymer light-emitting diodes (LEDs) was studied with respect to the driving voltage, electroluminescent luminance and efficiency. We observe that the ITO substrates aged for various times result in significant differences in optical and electrical characteristics which become worse as the ageing time increases. The optical and electrical performance of polymer LEDs is closely related to the surface properties of ITO substrate and the interface characteristics of ITO/polymer.  相似文献   

20.
在高分子溶液理论中引入Gibbs分布 ,用统计物理学方法重新推导出了聚合物溶液的热力学公式 .将高分子溶液的自由能和熵分三部分进行了计算 ,无热平动部分 ,无热构象部分和构象有热部分 .无热平动自由能和无热构象自由能分别等于Flory Huggins混合自由能公式的前两项 ,构象有热部分引入了Gibbs分布 ,考虑了链段 溶剂分子相互作用对高分子构象的影响 .在分子间的相互作用足够小时 ,又回到了FH公式  相似文献   

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