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1.
In this article, we review recent progress in the area of photorefractive polymers. Photorefractive (PR) polymers are multifunctional materials which combine photoconductivity and electro‐optic response to show a new phenomenon: light‐induced reversible modulation of the refractive index. Because of their multifunctional features, design, synthesis and preparation of these materials exhibiting high performance is an intellectual challenge. Moreover, numerous applications of photorefractive materials in optical devices have been established using inorganic materials. Utilizing the unique features of organic polymeric materials to prepare useful devices is an engineering challenge. In the past several years, research in this area has gained momentum because numerous new materials which possess better characteristic photorefractive parameters than their inorganic counterparts have been synthesized. Several interesting devices have been presented. Two different approaches have been developed to synthesize and prepare PR polymers, namely composite materials and fully functionalized polymers. Both approaches have had success in identifying new materials and in gaining understanding of the design principles of better materials. This paper discusses these aspects and gives a prospective view about this field.  相似文献   

2.
Organic materials in general and polymers in particular have traditionally been considered as to be phosphors and have been ruled out as materials which could be useful in dosimetry of ionizing radiations by thermoluminescence. Some results reported during the past decade suggested possibilities of organic phosphors with good thermoluminescence characteristics. Experiments were undertaken to exploit the various possibilities. The results show that “crystalline polymers” can have adequate thermoluminescence properties to be useful in dosimetry. It is suggested that further studies on thermoluminesence in crystalline polymers and highly drawn fibers of high polymers will prove fruitful.  相似文献   

3.
Side-chain functionalized polymers have a profound impact on complex materials synthesis with a variety of applications ranging from liquid crystalline and electro-optical materials to drug delivery systems. In the last decade, the use of self-assembly towards the synthesis of side-chain functionalized polymers has been investigated extensively as a result of its modular character and ease of synthesis. This tutorial review describes recent advances in the literature and establishes basic design principles and synthetic approaches towards the fabrication of supramolecular materials that are based on side-chain functionalized polymers.  相似文献   

4.
Summary: Polymers that have one of the three complementary colors (red, green, and blue, RGB) in the neutral state and high transmissivity in the oxidized state are the key materials towards use in electrochromic devices and displays. Although many neutral state red and blue polymers have been reported up to date, green polymers with highly transmissive oxidized states, high optical contrasts, fast switching times, and advanced long-term switching stabilities were essentially missing in the literature. This paper reviews our previous efforts towards realization of neutral state green polymers with highly transmissive oxidized state. The key to this problem was found to be the synthesis of donor-acceptor polymers bearing benzothiadiazole or quinoxaline derivatives as the acceptor and electron rich 3,4-ethylenedioxythiophene unit as the donor component. Green neutral state polymeric materials with highly transmissive oxidized state with excellent electrochromic properties have been realized with the design and synthesis of these types of materials. A solution processable green polymeric material has also been realized via chemical polymerization that has shown all superior properties of the electrochemically synthesized counterparts.  相似文献   

5.
含杯芳烃聚合物的合成与应用   总被引:4,自引:0,他引:4  
杯芳烃在主客体化学中是继冠醚和环糊精之后被广泛关注的第三代主体分子,能够选择性地与客体分子或离子形成络合物。近年来,含杯芳烃聚合物逐渐受到人们的重视。结合聚合物稳定性好,易于加工的特性,含杯芳烃聚合物将有望被开发成为新型功能高分子材料。本文详细介绍了含杯芳烃聚合物的合成及其应用。  相似文献   

6.
Capability of materials to self-repair is an innovative and unique property from a point of view both chemistry and physics. Moreover, such property could arouse special interests if such an ability could be caused by the selection of the environmental parameters. Such materials—polymers based on acryloyl-6-aminocaproic acid (A6ACA)—were synthesized in the present paper. In addition, mentioned polymers have been modified with different amount of magnetic nanoparticles solution. Subsequently, sorption capacity and behavior of synthesized polymers in simulated body fluids have been determined. What is also important, studies on cytotoxicity of prepared materials in relation to fibroblasts and cells of cancer origin have been conducted. Materials have also been analyzed by Fourier transform infrared spectroscopy and scanning electron microscopy method. Based on the research aiming at physicochemical characteristics of abovementioned materials it was proved that prepared hydrogels showed self-repair property in a low pH environment. Apart from this essential issue, these were characterized by high sorption capacity, high porosity which decreases with the introduced amount of nanoparticles and, what is important, cytotoxicity to cancer cells. Such combination is a very interesting from a point of view of many realms and due to its unique features may be widely applicable in the nearest future.  相似文献   

7.
Silica particles containing immobilised peptidic templates have been used for the generation of hierarchically imprinted polymers. The pores of the silica mould were filled with a mixture of monomers/initiator and polymerised, followed by dissolution of the silica template. This method leaves behind imprinted polymers with binding sites located at the surface, which are capable of recognising larger molecules with the same immobilised epitope. All the products resulting from solid-phase synthesis of peptides were characterised by elemental analysis, FT-IR spectroscopy and fluorescence microscopy. The hierarchically imprinted polymers generated from these products were characterised by elemental analysis, FT-IR spectroscopy, fluorescence microscopy, scanning electron microscopy (SEM) and nitrogen adsorption, providing evidence concerning the reproducibility of each step. The chromatographic properties of the materials have been investigated and the advantages of the immobilisation method have been proven. The materials exhibit selectivity for their templates and other structurally related dipeptides. Furthermore, the polymers proved to be capable of recognising larger peptides containing the immobilised sequence.  相似文献   

8.
Porphyrin polymers are of interest in relation to conductive materials[1, 2], catalysts for photosynthetic charge separation[3], or the fundamental features in biological systems[4]. There have been many versatile studies about them[5.6]. The one-dimensional "Shish Kebab"porphyrin polymers synthesized with a new method different from those reported and Schiff-base porphyrin polymers with two-dimensional nano-structure have provided a new field of study. The present paper covers highly ordered…  相似文献   

9.
The liquid crystalline behavior of low molecular weight compounds has been known for more than a century; synthetic polymers have been manufactured on a large scale for several decades, but just recently it was found possible to produce polymers using the structural principles of liquid crystalline compounds. The resulting materials have, as expected, unusual properties. Numerous applications, not only in opto-electronics, are already anticipated for such materials.  相似文献   

10.
Polymers containing liquid crystal groups have been studied previously as waveguides, and they have been deposited as spacer materials with various chromophores to form alternating films However, only a few members of this group of materials have been studied in any detail, and very little structural information has been obtained so far. Therefore, a more detailed examination of these materials as mono- and multilayers was undertaken. A new group of materials including the same mesogenic group, polymeric sulfones, was also studied. The polymers gave steep isotherms with high collapse pressures, indicating good packing of the monolayers, and could be deposited to form thick multilayers. X-ray diffraction showed that an ordered multilayer was formed, and the effects of the polymers chemical nature on the structure of the LB films are discussed. It appears that the dominant factor in monolayer structure is the nature of the polymer backbone rather than that of the liquid crystal side chains, which play a secondary role.  相似文献   

11.
Pure organic room-temperature phosphorescent(RTP) materials have been attracting widespread attention due to the unique properties and broad applications. However, RTP materials with the adjustable photochromic property are still a challenge.Based on this, two polymers containing hexaarylbiimidazole are strategically designed with dual emission of both fluorescence and phosphorescence. Furthermore, both polymers show sensitive photochromic responses from faint yellow to brown upon exposure to ultraviolet light. This study can enrich pure organic luminescent systems and provide new ideas for functional RTP materials.  相似文献   

12.
Supramolecular polymers, polymeric systems beyond the molecule, have attracted more and more attention from scientists due to their applications in various fields, including stimuli-responsive materials, healable materials, and drug delivery. Due to their good selectivity and convenient enviro-responsiveness, crown ether-based molecular recognition motifs have been actively employed to fabricate supramolecular polymers with interesting properties and novel applications in recent years. In this tutorial review, we classify supramolecular polymers based on their differences in topology and cover recent advances in the marriage between crown ether-based molecular recognition and polymer science.  相似文献   

13.
Self-assembly has been a powerful method to fabricate the polymer materials with well-defined structures and morphologies. Such assembled materials have shown wide potential applications in many fields such as nanomaterial, nanomedicine, lithography, and microelectronic. Crystallization has been a general behavior of stereoregular polymers. Besides the various noncovalent interactions, crystallization of polymer blocks or end groups can be an efficient way to manipulate the self-assembly pathway and assembled structures of polymers in both solid and solution. Crystallization-driven self-assembly has been widely implemented for the semicrystalline block copolymers (BCPs) and end-functionalized polymers. This minireview briefly presents the recent progresses in the crystallization-driven self-assembly of BCPs and end-functionalized polymers in both solid and solution states. Formation process, mechanism, and hierarchical structure of the crystallization-induced assemblies for BCPs and end-functionalized polymers are highlighted.  相似文献   

14.
In this review, we briefly summarized the remarkable progress of photo-responsive polymer materials from zero-dimensional micelles, twodimensional surfaces to three-dimensional hydrogels with irreversible or reversible moieties. Based on the photo-responsiveness, polymer have been designed, synthesized and applied for various biological fields including drug delivery and cell manipulation.  相似文献   

15.
This article presents an overview of the work that has been done recently in our laboratory concerning the development and application of new conjugated materials with tunable properties. We have designed polymers containing oligo(phenylenevinylene)-type conjugated segments of well defined size and structure isolated either in their main-chain or in the side-chains. Model oligomers corresponding to the conjugated parts of the polymers have also been studied. We show how these materials perform in light-emission applications (light-emitting diodes, lasers) or photovoltaic cells.  相似文献   

16.
Since the discovery of metallic conductivity in doped conjugated polymers (such as in doped polyacetylene),semiconducting properties of undoped conugated polymers have been drawn equal attentions. In additonal to the interests in the nonlinear properites of funda-mental excitations in these materials,possibilities of device applocations (such as solar cells and field -effect transistors) have been investigated in the past decade. However,the perfor-mance of polymer devices developed in early times was far from that of commercial devices made with inorganic materials (which was commonly attributed to the low carrier mobility of these materials),that managers and engineers in device industry dropped their initial in-terests gradually on this type of materials in later 1980' s.  相似文献   

17.
Photodegradable polymers constitute an emerging class of materials that finds numerous applications in biotechnology, biomedicine, and nanoscience. This article highlights some of the emerging applications of photodegradable polymers in the form of homopolymers, particles and self‐assembled constructs in solution, hydrogels for tissue engineering, and photolabile polymers for biopatterning applications. Novel photochemistries have been combined with controlled polymerization methods, which result in well‐defined photodegradable materials that exhibit light mediated and often controlled fragmentation processes.  相似文献   

18.
氢键型超分子聚合物的合成、结构与应用   总被引:2,自引:0,他引:2  
氢键型超分子聚合物是重复单元经氢键相互作用连接在一起的阵列,可生成液晶态,多样化的几何形状和高有序的凝聚态结构。氢键的温度敏感性和可逆性导致氢键型超分子聚合物具有和传统共价键结合的聚合物不同的性能。氢键型超分子聚合物是一类动态的智能型功能高分子材料,可在光化学、光电转换、非线性光学、弹性体、水凝胶和生物医用工程等领域广泛应用。本文从氢键型超分子聚合物化学(合成与机理)、物理(结构与性能)和工程(加工与应用)三个方面介绍氢键型超分子聚合物的进展。  相似文献   

19.
石墨烯作为一种新型二维平面纳米材料,表现出许多优异的物理性质.含偶氮苯的化合物和聚合物作为功能材料具有独特的光响应性质.将石墨烯的特性与偶氮材料的光响应性相结合,有望发展一类具有卓越性能的新型光电功能材料.本文总结了石墨烯/偶氮杂化材料这一研究方向的最新进展,重点介绍了杂化材料的制备、表征和光电功能性质等,并简要展望了这类材料的发展前景.  相似文献   

20.
Marine organisms such as plants, algae or small animals can adhere to surfaces of materials that are submerged in ocean. The accumulation of these organisms on surfaces is a marine biofouling process that has considerable adverse effects. Marine biofouling on ship hulls can cause severe fuel consumption increase. Investigations on antifouling polymers are therefore becoming important research topics for marine vessel operations. Antifouling polymers can be applied as coating layers on the ship hull, protecting it against the settlement and growth of sea organisms. Polyethylene glycol (PEG) is a hydrophilic polymer that can effectively resist the accumulation of marine organisms. PEG-based antifouling coatings have therefore been extensively researched and developed. However, the inferior stability of PEG makes it subject to degradation, rendering it ineffective for long-term services. Zwitterionic polymers have also emerged as promising antifouling materials in recent years. These polymers consist of both positively charged and negatively charged functional groups. Various zwitterionic polymers have been demonstrated to exhibit exceptional antifouling properties. Previously, surface characterizations of zwitterionic polymers have revealed that strong surface hydration is critical for their antifouling properties. In addition to these hydrophilic polymers, amphiphilic materials have also been developed as potential antifouling coatings. Both hydrophobic and hydrophilic functional groups are incorporated into the backbones or sidechains of these polymers. It has been demonstrated that the antifouling performance can be enhanced by precisely controlling the sequence of the hydrophobic-hydrophilic functionalities. Since biofouling generally occurs at the outer surface of the coatings, the antifouling properties of these coatings are closely related to their surface characteristics in water. Therefore, understanding of the surface molecular structures of antifouling materials is imperative for their future developments. In this review, we will summarize our recent advancements of antifouling material surface analysis using sum frequency generation (SFG) vibrational spectroscopy. SFG is a surface-sensitive technique which can provide molecular information of water and polymer structures at interfaces in situ in real time. The antifouling polymers we will review include zwitterionic polymer brushes, mixed charged polymers, and amphiphilic polypeptoids. Interfacial hydration studies of these polymers by SFG will be presented. The salt effect on antifouling polymer surface hydration will also be discussed. In addition, the interactions between antifouling materials and protein molecules as well as algae will be reviewed. The above research clearly established strong correlations between strong surface hydration and good antifouling properties. It also demonstrated that SFG is a powerful technique to provide molecular level understanding of polymer antifouling mechanisms.  相似文献   

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