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可变形液晶聚合物是近年来的研究热点,它们在人造肌肉、软机器人和智能光学设备等智能软系统的开发中表现出巨大潜力。然而,传统热响应液晶聚合物的应用通常受到聚合物基体的低热导率以及对外部加热装置高度依赖性的限制。相比之下,光控方法具有许多优点,包括具有非接触式、远程原位以及精确操纵的能力,这有助于开发各种不受限制且可远程操作的智能软器件。最近,通过引入有机或无机光响应组分作为功能添加剂来开发光控可变形液晶聚合物有许多重要进展。其中,通过功能模块、液晶相和聚合物基质之间的相互作用,所引入组分的多种功能可以与液晶聚合物的定向变形行为相结合。本文将重点介绍掺入光敏有机染料或无机纳米组分的可光操作液晶聚合物复合体系的设计策略、制造方法和工作原理,并简要总结它们可能的应用和未来的发展。 相似文献
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对呼吸图技术制备二维有序多孔结构的研究进展进行了综合评述, 并重点介绍了本课题组发展的静态呼吸图技术. 利用静态呼吸图法, 可制备高度有序的聚合物、聚合物/无机物微孔膜. 这些有序的结构可以直接应用于光掩膜. 进一步, 多孔聚合物膜可以被紫外光交联和改性. 表面改性的多孔聚合物膜可以用于细胞支架. 而交联的聚合物/无机物前驱体微孔膜可以用来制备无机纳米材料阵列. 结果表明, 静态呼吸图技术是一种简单、高效的对聚合物、聚合物/无机物薄膜进行图案化的通用方法,并展示了图案化薄膜广阔的功能化前景. 相似文献
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功能化和智能化是纤维发展的趋势.单一组分纤维难以满足日益发展的需求,而多组分纤维能够集中不同组分的特点,实现性能的集成与优化.通过非共价相互作用,高分子聚集而形成多组分均相体系,称为高分子复合物.利用高分子复合物的形成过程使纤维成型;或者直接利用高分子复合物进行纺丝而得到的纤维称为高分子复合物纤维.高分子复合物纤维,各组分可以达到分子层面上的相容性,给我们提供了一个功能纤维和智能纤维设计开发的平台.本文详细阐述了各类高分子复合物纤维的研究现状,并展望高分子复合物纤维的未来发展. 相似文献
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《有机化学》2020,(8)
有机-无机复合荧光纳米材料制备简便,生物相容性好,成像性能优异,在化学和生物传感、生物成像、催化及能源材料等领域受到很多关注.传统的荧光有机小分子与无机材料复合时,常发生荧光猝灭,而聚集诱导发光(Aggregation-InducedEmission,AIE)有机小分子在聚集态具有高发光量子产率,为有机-无机复合荧光纳米材料的研究提供了机遇.由于AIE有机小分子功能化的无机纳米材料独特的优点,人们对其设计、合成及应用进行了较多研究.综述了AIE有机小分子和多种类型的无机纳米结构(金属纳米颗粒、钙钛矿材料、层状材料、氧化物、硫化物等)复合材料的制备和应用的新进展,特别是在化学和生物传感、生物成像、药物输运、光热治疗、催化以及能源等领域的应用,并对其发展前景进行了展望. 相似文献
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基于无机材料-微生物复合半人工光合系统是在自然光合作用和人工光合作用研究进展到一定阶段,为克服各自的缺陷,实现微生物与无机材料优势互补而发展出来的一种研究体系。该体系的主要优势是将微生物的催化选择性与无机材料的光响应性结合起来,旨在解决人工光合作用体系催化选择性差的问题。目前,可以通过光催化剂-微生物复合和电极-微生物复合来实现基于无机材料-微生物复合的半人工光合作用。本文围绕基于无机材料-微生物复合的半人工光合作用,依次从半人工水氧化、半人工光合还原和材料-微生物界面等方面做了系统的阐述,重点介绍基于电极-微生物复合的半人工光合体系研究进展,对基于无机材料-微生物复合的半人工光合作用的领域现状做了分析和总结,并且对该领域的前景进行了展望。 相似文献
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Organic-inorganic polymer composites, consisting of a polyurethane organic phase and a mineral inorganic phase were prepared by the joint polymerization of the urethane oligomer with the water solution sodium silicate. The structure and the morphology of the composites, at a fixed weight fraction of the inorganic component of 20%, and of the corresponding pure polyurethane matrices were investigated by wide-angle and small-angle X-ray scattering (WAXS and SAXS, respectively). The results show similar size (5-7 nm) of the scale of heterogeneity of the composites due to the microphase separation of the rigid and the flexible blocks of the amorphous polyurethane matrix and due to the inorganic crystalline inclusions, i.e. the materials prepared are nanocomposites. The WAXS measurements indicate that the individual properties of the block inorganic component are lost in the nanocomposites, probably due to physical and chemical interactions between the two components. Water sorption from the liquid phase was studied gravimetrically in a composite and in the corresponding polyurethane. The results show high sorption capacity of the composite, due to the hydrophilicity of the inorganic phase and the elasticity of the polyurethane matrix, and allow to estimate the layer thickness of water adsorbed on the inorganic nanoparticle surface to about 20 nm, in reasonable agreement with a model adopted from the literature. WAXS and SAXS measurements on the swelled composite and the swelled-and-dried composite indicate changes in the structure of the inorganic component induced by water, which are, however, to a large extent reversible. These materials may find applications as gel electrolytes and as hydrogels in drug delivery systems. 相似文献
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Polymer nanocomposites containing layered silicates have been considered as a new generation of composite materials due to their expected unique properties attributed to the high aspect ratio of the inorganic platelets. Nevertheless, addition of layered silicates to polyolefins mostly results in phase separated systems because of the incompatibility of the silicates with the non-polar polyolefins. Functional compatibilizers are required to enhance the interactions and alter the structure from phase separated micro-composites to intercalated and exfoliated nanocomposites. Commercial macromolecular compatibilizers (mainly maleic-anhydride-functionalized polyolefins) are most commonly used to improve the interfacial bonding between the fillers and the polymers whereas specifically synthesized functional homopolymers or copolymers have been utilized as well. In this article, we are reviewing a number of investigations, which studied the influence on the composite structure of various parameters like the compatilizer to inorganic ratio, the type and content of the functional groups and the molecular weight of the functional additive, the miscibility between the matrix polymer and the compatibilizer, the kind of surfactants modifying the inorganic surface, the processing conditions, etc. The most important results obtained utilizing maleic-anhydride-functionalized polyolefins are discussed first, whereas a summary is presented then of the studies performed utilizing other functional oligomers/polymers. X-ray diffraction and transmission electron microscopy studies supported by rheology indicate that the most important factor controlling the structure and the properties is the ratio of functional additive to organoclay whereas the miscibility between the matrix polymer and the compatibilizer is a prerequisite. 相似文献
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Incorporating inorganic particles into conjugated polymer matrices is an area of current interest in the fields of optoelectronics and solar energy. The hybrid nanocomposites exhibit interesting physical properties thanks to good optical properties of polymers and to high carrier mobility of inorganic semiconductors. A judicious combination of organic/inorganic can therefore provide materials of low cost, ease processing, high stability, with specific electrical and optical properties.In the present study, we briefly review the composite materials that have been successfully utilized in the field of optoelectronics and photovoltaic conversion. We shall describe in particular a family of nanocomposites using polyhedral oligomeric silsesquioxanes (POSS) of general formula (RSiO3/2)n where R is an organic group as a core. The composites are made by grafting functional polymer groups to the core, which allows the control of their optical properties. Such composites have high mechanical resistance and stability because of the special structure of the core. For illustration, we present a study of polyfluorene (PF)/POSS materials used as an active layer in organic light emitting diodes, with improved performance as compared to those using polymer only, and we discuss the role of the particles in the transport and emission processes in the devices studied. 相似文献
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Graphene-based composites 总被引:8,自引:0,他引:8
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INVESTIGATION OF STRUCTURE AND PROPERTIES FOR POLYMER SYSTEMS BASED ON DYNAMIC RHEOLOGICAL APPROACHES 总被引:2,自引:0,他引:2
MinZuo QiangZheng 《高分子科学》2005,(4):341-354
The dynamic theological measurements have been a preferred approach to the characterization of the structure and properties for multi-component or multi-phase polymer systems, due to its sensitive response to changes of structure for these heterogeneous polymers. In the present article, recent progresses in the studies on dynamic theology for heterogeneous polymer systems including polymeric composites filled with inorganic particles, thermo-oxidized polyolefins, phaseseparated polymeric blends and functional polymers with the scaling and percolation behavior are reviewed, mainly depending on the results by the authors‘ group. By means of theological measurements, not only some new fingerprints responsible for the evolution of morphology and structure concerning these polymer systems are obtained, the corresponding results are also significant for the design and preparation of novel polymer-based composites and functional materials. 相似文献
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Lei Li Huaming Wang Sixun Zheng 《Journal of polymer science. Part A, Polymer chemistry》2024,62(3):583-613
Polyhedral oligomeric silsesquioxanes (POSS) are a class of well-defined organic–inorganic stereo molecules comprising inorganic Si O Si cores and peripheral organic moieties. Since they were first reported in 1946 by Scott et al., there have been a great number of investigations on the use of POSS macromers as the building blocks to access the organic–inorganic composites with polymers. In most of cases, monofunctional POSS macromers are employed and the linear hybrid polymers are obtained. Under this circumstance, POSS cages act as the side or end groups whereas the main chains of the polymers remain unchanged. Occasionally, octafunctional POSS macromers are involved, resulting in the generation of crosslinked (or network-like) hybrids. Recently, well-defined difunctional POSS macromers have increasingly provoked a considerable attention of investigators. From the synthetic methodology of POSS macromers to the approaches to introduce them into polymers, difunctional POSS macromers have the features quite different from mono- (or octa-) functional POSS. More importantly, the related organic–inorganic hybrids possess the different morphologies and properties. In the past years, there has been a rapid increase in the number of literatures on the studies on well-defined difunctional POSS and the related organic–inorganic hybrids. Nonetheless, the related review is lacking. In this contribution, we would summarize the recent progress in this regard, from the synthesis of POSS macromers, the approaches of introducing the POSS macromers into polymers to the correlation of morphologies with properties of the organic–inorganic hybrids. In addition, perspectives and challenges for the further advancement are envisaged and discussed. 相似文献
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两种经过化学修饰的PPV(聚对苯撑乙烯)类共轭高分子共聚物分别与纳米TiO2复合,作为有机/无机复合材料进行研究.这两种共聚物在乙醇、二氯甲烷溶液中分别与以Sol-Gel法、反胶束法制得的TiO2共混得到均匀分散的体系而不出现相分离.用共聚物与TiO2的复合液可以在石英基底上制成均匀的复合膜.结果表明,高聚物/TiO2复合物的光物理特性与单纯的高聚物相比呈现明显的差异;不同粒径的纳米TiO2对复合物性能的影响不同;中间苯环的取代基对共聚物的性质影响明显.共轭高分子与纳米TiO2复合涂膜后其发光性能明显改善,有作为发光器件的应用前景. 相似文献
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Functional inorganic nanofillers for transparent polymers 总被引:6,自引:0,他引:6
The integration of inorganic nanoparticles into polymers has been used for the functionalization of polymer materials with great success. Whereas in traditional polymer composites, micron sized particles or agglomerates typically cause significant light scattering hampering optical applications, in nanocomposites the particle dimensions are small enough for the production of highly transparent composites. A challenge for the generation of such materials is to develop an integrated synthesis strategy adapting particle generation, surface modification and integration inside the polymer. Surface grafting using polymerizable surfactants or capping agents allows for linking the particles to the polymer. Novel techniques such as in situ polymerization and in situ particle processing are beneficial to avoid aggregation of inorganic particles inside the polymer matrix. The functions associated with inorganic fillers are widespread. Layered silicates and related materials are nowadays commercially available for improving mechanical and barrier properties in packaging. With the availability of highly transparent materials, the focus has shifted towards optical functions such as luminescence and UV-protection in transparent polymers. IR-active fillers are used in laser-holography for transparent poly(methyl methacrylate) (PMMA) nanocomposites. Refractive index modulation and ultrahigh refractive index films were developed based on inorganic materials such as PbS. The integration of magnetic nanoparticles has a great potential for applications such as electromagnetic interference shielding and magneto-optical storage.This tutorial review will summarize functions associated with the integration of inorganic nanofillers in polymers with a focus on optical properties. 相似文献
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Supramolecular polymers constructed by orthogonal self-assembly based on multiple hydrogen bonding and macrocyclic host-guest interactions have received increasing attention due to their elegant structures,outstanding properties,and potential applications.Hydrogen bonding endows these supramolecular polymers with good adaptability and reversibility,while macrocyclic host-guest interactions give them good selectivity and versatile stimuli-responsiveness.Therefore,functional supramolecular polymers fabricated by these two highly specific,noninterfering interactions in an orthogonal way have shown wide applications in the fields of molecular machines,electronics,soft materials,etc.In this review,we discuss the recent advances of functional supramolecular polymers fabricated by orthogonal self-assembly based on multiple hydroge n bonding and host-guest interactions.In particular,we focus on crown ether-and pillar[n]arene-based supramolecular polymers due to their compatibility with multiple hydrogen bonds in organic solution.The fabrication strategies,interesting properties,and potential applications of these advanced supramolecular materials are mainly concerned. 相似文献