Supramolecular polymers: from scientific curiosity to technological reality

Supramolecular polymers^[1] are introduced as a new approach to come to materials in which the repeating units are not connected by covalent bonds but by specific secondary interactions. Self-complementary quadruple hydrogen bonded structures with high association constants are presented as easy to synthesize fragments in supramolecular polymers. Some of the many possibilities of equilibrium polymers are discussed, while it is shown that these supramolecular polymers can obtain materials properties normally only obtained with macromolecules.     

一种含螺吡喃和肉桂酸酯双光功能基团的光致变色染料的合成与性能

合成了一种含有光致聚合肉桂酸酯基团的新型光致变色螺吡喃染料,研究其与普通螺吡喃染料在不同高分子材料中的光致变色和热退色过程(PMMA和PVCi).通过UV-Vis光谱、NMR谱和IR光谱研究了新型染料中的肉桂酸酯基团的光致聚合过程,考察了其对螺吡喃结构的光致变色显色体热稳定性的影响.     

The Impact of Charge‐Distribution on Photochromic Properties in 1D Coordination Polymers

The reaction of CdCl₂ · 2.5H₂O with 1,1′‐bis(3‐carboxybenzyl)‐4,4′‐bipyridinium dichloride (H₂L1 · Cl₂) or 4,4′‐bis[(3‐carboxypyridino)methyl]‐biphenyl dichloride (H₂L2 · Cl₂) in a dimethylformamide/methanol mixed‐solvent system at room temperature, affording the complexes [(CdCl₂)₃(L1)₃]_n ( 1 ) and {[CdCl₂(L2)(H₂O)₂] · 2H₂O}_n ( 2 ). They were characterized by elemental analyses, IR spectroscopy, and single‐crystal X‐ray diffraction. Both 1 and 2 exhibit 1D coordination networks, which further stack into a 3D supramolecular structure by hydrogen bonding and π–π interactions. Furthermore, these two complexes exhibit different photochromic behavior in the solid state, which may originate from different charge‐distributions of H₂L1 · Cl₂ and H₂L2 · Cl₂ ligands.     

新型含二茂铁基螺苝嗪类光致变色化合物的合成及其光谱研究

合成了一种新的含二茂铁基螺 嗪类光致变色化合物 ,并研究了其吸收光谱和荧光光谱。发现在分子内引入二茂铁基团提高了热不可逆性 ,发生光致变色反应前后化合物结构的不同对其荧光特性影响很大     

联苯基团修饰的联茚满二羟基烯二酮的合成与性质

合成了联苯基团修饰的联茚满二羟基烯二酮2a和2b, 研究了其光致变色、光致自由基和液晶性质, 讨论了结构与性质之间的关系. 结果表明, 两种目标化合物在固态下均具有光致变色和光致自由基性质, 但都不具有液晶性质. 当联苯基团与联茚满二羟基烯二酮母体结构单元之间的烷氧基链较短时, 光致变色现象更显著.     

Bonding and molecular environment effects on photoorientation in epoxy-based polymers having azobenzene units

An azo prepolymer (TAZ) was synthesized by reaction between Disperse Orange 3 (DO3) and diglycidyl ether of bisphenol A (DGEBA). The resulting TAZ was blended with DGEBA and two different monoamines, one aliphatic and one aromatic, benzylamine (BA) and m-toluidine (MT), to prepare various azo copolymers with different azo contents. In addition, two guest-host systems were prepared: 5.16% by weight of DO3 in DGEBA-BA and in DGEBA-MT polymers. Their reversible optical storage properties were studied and compared. The maximum obtainable birefringence increases linearly with TAZ weight fraction, independently of the power of the writing beam, the environment in which the azo moiety is located, and the bonding between the dye and the matrix. It was found that, in BA-based copolymers, with lower T_g, the fraction of birefringence conserved after relaxation is smaller and the writing rates are higher than in MT-based copolymers. The film thickness dependence of the birefringence signal is also analyzed.     

Review of the recent progress in photoresponsive molecularly imprinted polymers containing azobenzene chromophores

Photoresponsive molecularly imprinted polymers (PMIPs) containing azobenzene have received wide research attention in recent years and made notable achievements. This article reviews the recent developments on PMIPs containing azobenzene. Topics include the following: (i) brief introduction of azobenzene, molecularly imprinted polymers, and PMIPs containing azobenzene; (ii) progress in functional monomers, cross-linkers, and polymerization conditions; (iii) preparation methods, properties, applications, as well as advantages and disadvantages of conventional PMIPs; (iv) substrate, preparation method, and applications of photoresponsive surface molecularly imprinted polymers; and (v) some perspectives for further development of PMIPs containing azobenzene.     

(口恶)唑环取代的俘精酸酐的合成及其光致变色性能的研究

合成了含噁唑环的俘精酸酐,4-（5-甲基-2-对甲氧苯基-4-乙酰基嘿唑）乙叉（异丙叉）丁二酸酐,研究了该化合物在不同溶剂中的光致变色性能,进行了光成色和光消色过程的动力学研究,并考察了溶剂极性对该化合物吸收光谱的影响。稳态动力学分析结果表明,该化合物呈色体的光消色反应遵循一级动力学规律,俘精酸酐本身的光反应比较复杂,不符合简单的动力学级数。     

唑环取代的俘精酸酐的合成及其光致变色性能的研究

合成了含     

Spectral Properties and Photochromic Characteristics of Spiropyran Dyes

IntroductionSince the last decade, a large number of workshave concentrated on the photochromic behavior of in-dolinospirobenzopyran dyes[1—4]. Interest in these com-pounds has been concerned with the reversibility of thetransformation between the colorl…     

钛凝胶的光致变色和电致变色特性

Titania gel is very sensitive to change of color to blue-purple by UV irradiation and to brown color under extra electric field polarzation. The UV absorption spectra of the photochromic (PC) and electrochromic(EC) titania gel are different to that of the nanocrystalline TiO_2 which changes to blue color by UV irradiation or under extra electric field polarization. The steady-state ESR measurements at room temperature indicate that ESR signals of Ti3+ appeared in PC and EC titania gel with the g values corresponding to 1.9505 and 1.9512, respectively.     

Photochromic and fluorescence properties of coumarin fulgimides

Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation.     

新型双螺噁嗪分子的合成及性能

设计合成了3个双螺噁嗪化合物, 采用核磁共振谱、红外光谱和高分辨质谱对这些化合物进行了表征. 测试了光照前后化合物在不同溶剂中的紫外吸收光谱、荧光光谱以及在高分子薄膜中的消色动力学曲线. 结果表明, 目标化合物均具有良好的光致变色性能和耐疲劳度, 在材料、分子开光及生物探针领域有潜在的应用前景.     

钛凝胶的光致变色和电致变色特性

过渡金属氧化物光致变色［１,２］和电致变色［３－７］材料在图象显示、信息存储以及做为调节光线强弱的“灵巧窗”等方面有着潜在的应用．国内外广大的科研工作者,在新型光电变色材料的寻找和光电变色机理等方面开展了较广泛而深入的研究．目前普遍认为变色机理为双注...     

二甲基二氢芘类光致变色化合物及其光开关性质

介绍了二甲基二氢芘类化合物特殊的逆光致变色性质,讨论了内外取代基、间隔基以及稠合基团等因素对二甲基二氢芘光致变色性质的影响,综述了该类化合物在光学开关和信息的光化学读出等应用方面的研究状况,并展望了二氢芘类光致变色化合物的研究前景。     

Separation of living and dead polymers in synthetic polypeptide mixtures by nonaqueous capillary electrophoresis using differences in ionization states

The complexity in the mechanisms of polymerization of N-carboxyanhydrides requires the development of new analytical techniques able to separate mixtures of synthetic polypeptides. This work focuses on the separation of poly(N(epsilon)-trifluoroacetyl-L-lysine) (PTLL) mixtures by nonaqueous capillary electrophoresis (CE). The main goal of this work was to find electrophoretic conditions that permit the separation and the quantification of the dead polymer families that were previously identified in the samples. The influence of the pH of the electrolyte on the selectivity of the separation was carefully investigated. The mechanisms of separation of the PTTLs are discussed as a function of their ionization state. The separations obtained on a noncovalently coated capillary were compared with those obtained on a fused-silica capillary. Finally, using two different electrolytes, it is possible to quantify the three families of PTLLs, namely, the living PTLLs, the dead PTLLs with N-formyl end group and the dead PTLLs with a carboxylic end group. These results confirm the importance of CE for the separation of synthetic organic polymers in nonaqueous electrolytes.     

含席夫碱基的螺吡喃双功能光致变色材料的合成及性质

设计合成了一系列含席夫碱基的螺吡喃双功能光致变色材料4a~4n. 通过1H NMR, IR和HRMS对其结构进行了表征. 研究了化合物在几种溶剂和PMMA膜中的光致变色性质, 研究了化合物4a在甲醇中, 以及化合物4a和4f在高分子介质聚甲基丙烯酸甲酯(PMMA)中的消色过程. 结果表明, 化合物4e在PMMA膜中光照后呈现出与其它化合物不同的颜色, 为罕见的绿色. 化合物4a在二氯甲烷溶液中有良好的荧光性能. 所合成的新型含席夫碱基的螺吡喃双功能光致变色材料在甲醇、二氯甲烷和环己烷溶液中及在PMMA膜中均表现出良好的光致变色性质.     

Keggin结构钨磷酸/聚乙烯吡咯烷酮复合膜的制备和光致变色性质研究

近年来,由于无机－有机复合材料具有潜在的应用前景和特殊性能,尤其是光致变色性能,引起研究者们的广泛兴趣^[1-3],以杂多化合物为多核配合物,通过化合键或氢键作用与高分子底物结合,形成电荷转移物质,可以大大提高复合材料的化学和物理性能。目前,这一领域的研究在国外已经成为热点^[4-7]。本文以Keggin结构钨磷酸和聚乙烯吡咯烷酮为原料,报道了该类复合物的合成、表征及光致变色性质。     

含席夫碱基的螺噁嗪类光致变色化合物的合成及性质

设计合成了一系列含席夫碱基的螺噁嗪双功能光致变色材料4a~4d. 通过¹H NMR, ¹³C NMR, IR和HRMS对其结构进行了表征. 新化合物在几种有机溶剂中均表现出了良好的光致变色性. 研究了化合物在几种高分子膜中的光致变色性. 比较了化合物4b的开环体在两种不同溶剂, 即甲醇和二甲亚砜, 以及3种高分子介质, 即聚甲基丙烯酸甲酯(PMMA)、聚乙烯醇缩丁醛(PVB)和聚乙烯醇(PVA)中的消色速率. 研究了化合物在甲醇、二甲亚砜、PMMA及PVB中的消色过程动力学, 根据化合物在溶液中和高分子介质中开环体消色过程的差别, 推测了存在两种动力学解释的原因. 研究结果显示, 化合物4d在PMMA膜中的耐疲劳度良好.     

Impact of open-shell loading on mass transport and doping in conjugated radical polymers

Radical-containing polymers are an evolving class of redox-active macromolecules that have received great interest; however, most reports regarding radical polymers have focused on materials with nonconjugated backbones because their application drivers did not require this conjugation. Conversely, there has been a recent rise in the development of radical polymers for next-generation applications where imparting conjugation to the backbone of the radical polymer could be of significant benefit. To this end, we designed and synthesized a series of 3,4-propylenedioxythiophene (ProDOT)-based polymers bearing nitroxide radical pendent groups via direct arylation polymerization. Specifically, we present four radical polymers with open-shell loadings ranging from 24% to 82% of the total number of repeat units per polymer chain. The impact of open-shell loading on the electrochemical behaviors of these polymers in different electrolytes was then established using cyclic voltammetry, spectroelectrochemical analyses, and electrochemical quartz-crystal microbalance with dissipation monitoring. We demonstrate that incorporating the open-shell moieties in the ProDOT-based polymers lowers the oxidation onset potential of the conjugated backbone and increases the solvent and ion uptake significantly. Thus, this effort provides a clear picture of the mass transfer and doping mechanism of the ProDOT-based radical polymers to aid in guiding their future design.