New chemically prepared conducting “pyrrole blacks”

A series of electrically conducting pyrrole “black” polymers has been prepared by chemical oxidation of pyrrole with a variety of ferric salts. The synthesis and properties of these materials are described and compared with electrochemically-prepared analogs. Pyrrole “blacks” with strong acid anion “dopants” exhibited the highest conductivities, up to 62 Ω cm^?1 for the triflate-doped polymer. The adjustability and ease of synthesis of the ferric-derived polypyrroles render these particularly promising for large-scale processing of conducting polymers.     

Analytical characterization of polymers used in conservation and restoration by ATR-FTIR spectroscopy

In the last few decades many new polymers have been synthesized that are now being used in cultural heritage conservation. The physical and chemical properties and the long-term behaviors of these new polymers are determined by the chemical composition of the starting materials used in their synthesis along with the nature of the substances added to facilitate their production. The practical applications of these polymers depend on their composition and form (foam, film, sheets, pressure-sensitive adhesives, heat-seal adhesives, etc.). Some materials are used in restoration works and others for the exhibition, storage and transport of works of art. In all cases, it is absolutely necessary to know their compositions. Furthermore, many different materials that are manufactured for other objectives are also used for conservation and restoration. The technical information about the materials provided by the manufacturer is usually incomplete, so it is necessary to analytically characterize such materials. FTIR spectrometry is widely used for polymer identification, and, more recently, ATR–FTIR has been shown to give excellent results. This paper reports the ATR-FTIR analysis of samples of polymeric materials used in the conservation of artworks. These samples were examined directly in the solid material without sample preparation.     

导电高分子在神经界面电极中的应用

神经界面电极作为人体和外部器件间信息融合的媒介, 为人们进一步探究神经系统高级功能的机制提供了有效工具. 传统的神经电极多以金属和半导体材料为主, 这两类材料因具有惰性材料的特性及优越的 导电性能而成为早期神经电极的主要制备材料, 但由于其刚性过大和光滑表面导致的机械失配及与生物组织间过高的电化学阻抗限制了神经电极的进一步发展. 导电高分子作为一种有机导电材料, 同时具备柔软性 (杨氏模量约在0.01~10 GPa)和导电性(高掺杂度的导电高分子的电导率在金属范围, 10⁰~10⁵ S/cm)的特征, 是制备神经电极的有效材料. 近年来, 人们利用导电高分子材料对传统电极材料进行改性甚至替代, 以提高电极比表面积、 减小界面阻抗, 并提高电极检测的灵敏性; 同时减小电极与组织间的应变失配, 减少炎症反应, 并进一步在导电高分子中引入功能性生物大分子, 减少生物组织对电极的排异反应, 增加电极在体内长期植入的稳定性. 本文讨论和总结了导电高分子材料在神经电极中的应用, 分别对导电高分子作为涂层修饰神经电极、 全导电高分子材料神经电极及导电高分子复合材料神经电极等展开讨论, 分析了导电高分子在神经界面电极中的应用前景及存在的问题, 以期对神经界面电极在脑科学和生物电子医疗等前沿领域的进一步发展提供参考.     

Polymer Alloys—Their Structure,Morphology, and Properties

Polymeric materials with novel properties for new technological applications are increasingly obtained by combining existing polymers, while the synthesis of new monomers has receded into the background. These polymer combinations or “alloys” (polyblends) are characterized by their chemical composition, the conformation of the chain molecules, and the morphology, i.e. the state of order at supramolecular level. Multiphase constitution is a typical characteristic of these substances, with a decisive influence on their macroscopic properties. The morphology of multiphase polymer alloys can be controlled to a limited extent via the chemical composition of their components when homopolymers are mixed in the melt or as dispersions. Graft copolymerization, on the other hand, makes it possible to achieve the desired morphology at a given chemical composition. Furthermore, transprent two-phase polymer alloys can be obtained under certain conditions. In multiphase polymers the reduction of stress without fracture, caused by mechanical loading will be treated using models. Certain combinations of properties such as hardness and toughness are connected with the coexistence of disperse and continuous phases. Equilibrium thermodynamical criteria for liquid mixtures wil be used to explain demixing phenomena in polymers. In the last few years it has become possible to determine the chain conformation experimentally using neutron scattering.     

导电聚合物的纳米结构及其在生物医学领域的应用

由于表面效应、小尺寸效应和量子效应,使纳米结构的导电聚合物材料与传统聚合物材料相比,显示出更优越的性能。基于神经组织对电场和电刺激敏感性,使得导电聚合物纳米材料在生物医学应用方面很有前景。本文综述了纳米结构的导电聚合物的合成方法,及其在生物医学领域的应用。合成方法主要关注于硬模板法、软模板法和无模板自组装法,以及这些方法中导电聚合物纳米结构的形成机理。总结了具有纳米结构的导电聚合物,如纳米颗粒、纳米纤维和纳米管等作为神经电极涂层材料和生物传感器等方面的应用。     

Synthesis of Electrolyte Polymer Based on Natural Polymer Chitosan by Ion Implantation Technique

This research is conducted to make solid-state electrolyte based on natural polymers, as an alternative material for energy storage such as battery. Natural polymers as materials of solid state batteries have various benefits, such as unlimited abundance, biodegradable, unleakage, stable form, excellent process, and electrochemical stability, compare to the liquid ones. In this study, a solid state polymer electrolyte based on natural polymer such as chitosan was synthesized by incorporating various ion salts (Li, Cu, Ag) in the polymer matrix. The synthesis of solid-state electrolyte polymer was carried out by casting method to make a thin polymer film. Then the ionic (Li, Cu, Ag) doping with various implant dose will be applied to the thin polymer film matrix by ionic implantation technique. The implanted polymer electrolytes are then characterized their conductivities, micro structures, and crystal structures by high precision LCR, scanning electron microscopy-electron dispersive spectroscopy (SEM-EDS), and X-ray diffraction (XRD), respectively. The measured of conductivities showed that thin film polymers after implanted with ionic Li, Cu or Ag were increased the conductivity, meanwhile elemental analisys by electron dispersive spectroscopy indicated that ionic implant to chitosan was success. The modification of chitosan polymer to become electrolyte polymer can be concluded.     

Effect of Oxygen on Surface Properties and Drug Release Behavior of Plasma Polymer of n-Butyl Methacrylate

The effects of oxygen on the chemical structure, morphology, hydrophilicity and drug release behavior of radio-frequency plasma poly n- butyl methacrylate （PPBMA） thin film were carded out for the first time. ATR-FTIR and XPS showed that oxygen had little influence on the chemical structure and composition of PPBMAs, which did not agree with the thought that the presence of oxygen gas would increase the oxidized carbon functionalities in the plasma polymer. SEM and static contact angle measurement indicated that in case of deposition with oxygen, the smoothness and hydrophilicity of PPBMA were dramatically improved. The drug release behavior showed that drug release from the PPBMA coating without oxygen was biphasic patterns, while from PPBMA coating with oxygen was Higuchi release. These results were helpful for the design and tailoring of the PPBMA polymer film and other of plasma polymers film, but could provide a new idea for the drug release controlled form.     

Aliphatic polyester polymer stars: synthesis, properties and applications in biomedicine and nanotechnology

A critical review: the ring-opening polymerization of cyclic esters provides access to an array of biodegradable, bioassimilable and renewable polymeric materials. Building these aliphatic polyester polymers into larger macromolecular frameworks provides further control over polymer characteristics and opens up unique applications. Polymer stars, where multiple arms radiate from a single core molecule, have found particular utility in the areas of drug delivery and nanotechnology. A challenge in this field is in understanding the impact of altering synthetic variables on polymer properties. We review the synthesis and characterization of aliphatic polyester polymer stars, focusing on polymers originating from lactide, ε-caprolactone, glycolide, β-butyrolactone and trimethylene carbonate monomers and their copolymers including coverage of polyester miktoarm star copolymers. These macromolecular materials are further categorized by core molecules, catalysts employed, self-assembly and degradation properties and the resulting fields of application (262 references).     

Biomedical application of responsive ‘smart’ electrospun nanofibers in drug delivery system: A minireview

Electrospinning is a versatile method for producing continuous nanofibers. It has since become an easy and cost-effective technique in the manufacturing process and drawn keen interests in most biomedical field applications. Nanofibers have garnered great attention in nanomedicine due to their resemblance with the extracellular matrix (ECM). Like nanoparticles, its unique characteristics of higher surface-to-volume ratio and the tunability of the polymers utilizing nanofiber have increased the efficiency in encapsulation and drug-loading capabilities. Smart or “stimuli-responsive” polymers have shown particular fascination in controlled release, where their ability to react to minor changes in the environment, such as temperature, pH, electric field, light, or magnetic field, distinguishes them as intelligent. Polymers are a popular material for the design of drug delivery carriers; consequently, various types of drugs, including antiviral, proteins, antibiotics, DNA and RNA, are successfully encapsulated in the pH-dependent nanofibers with smart polymers which is a polymer that can respond to change such as pH change, temperature. In this minireview, we discuss applications of smart electrospun pH-responsive nanofibers in the emerging biomedical developments which includes cancer drug targeting, oral controlled release, wound healing and vaginal drug delivery.     

由聚合物门控的介孔二氧化硅基刺激响应性药物递送系统

本文主要介绍了以聚合物体系作为门控构筑的基于介孔二氧化硅纳米粒子的刺激响应性药物控释体系, 并根据聚合物类别将门控体系分为聚合物刷、 聚合物交联网络和聚合物包裹层三类. 根据聚合物“阀门”与无机纳米粒子的共价或非共价连接方式, 综述了这些杂化材料在不同外界刺激作用下的药物控制释放行为, 并给出该领域所面临的机遇和挑战.     

开环易位聚合合成瓶刷聚合物

瓶刷聚合物是一类具有独特侧链结构的梳形聚合物。功能性瓶刷聚合物在光子晶体、表面活性剂、医药载体、防污涂层以及智能材料等领域具有良好的应用价值。通过开环易位聚合合成瓶刷聚合物的方法具有合成步骤简单、聚合物接枝密度高和侧链组成均一等优点,在控制聚合物组成、分子量和分散性等方面具有显著优势。本文基于开环易位聚合,简述了合成瓶刷均聚物以及嵌段型、混合型和核-壳型三种类型的瓶刷共聚物的方法,并介绍了合成精确结构的瓶刷聚合物的新进展。     

Non-covalent side-chain polymers: design principles, functionalization strategies, and perspectives

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.     

Fabrication and Optical and Electrical Properties of Poly(2,5-di-n-butoxyphenylene) Nanowire Arrays

Regular patterned arrays of nanomaterials have been widely fabricated and studied for their benefits in construction of novel type of optical, electron and magnetic device1-2, these kinds of devices center on the inorganic materials. With the development of synthesis and application of new type of polymer material, the design and construction of organic nanopolymer have become a great interest. Poly(p-phenylene)(PPP) and some derivatives have been widely investigated as a candidate for high strength, high temperature and conducting polymers, and can be used as electrode materials in electrochemical cells, blue emitting diodes: The polymers obtained by oxidative coupling polymerization of benzene nuclei with aluminum chloride and copper(Ⅱ) chloride is insoluble in all solvent and inflexible, which hinders revealing their basic properties. Introduction of flexible side chains into the aromatic rings can not only render solubility and processibility, but also improve or modify optical and electrical properties of the polymers. As a further step in assembling method and optoelectronic studies, it is attractive to investigate the properties of photoluminescence and electroluminescene of regular patterned arrays of poly(p-phenylene) deriva-tives nanowires.     

Thermosensitive polylactide‐glycolide delivery systems for treatment of narcotic addictions

Environmental switches may be fabricated for the controlled release of pharmaceutical drug using a thermally responsive polymer with the intrinsic chemical and physical nature of stimuli‐sensitive smart materials. Particularly, much attention has been paid to the biomedical applications of poly(N‐isopropyl acrylamide) (PNIPAAm) because of its unique reversible transition at a specific lower critical solution temperature (LCST).Thermally sensitive block copolymers, poly(N‐isopropyl acrylamide‐b‐poly(L ‐lactide‐co‐glycolide) (PNIPAAm‐b‐PLGA), and polyethylene glycol‐poly (lactide‐co‐glycolide) (PEG‐PLGA) triblock copolymers with different compositions and length of PLGA block were synthesized via ring‐opening polymerization of lactide and glycolide in the presence of OH‐terminated PNIPAAm or PEG. The composition and structure of the polymer were determined by NMR and FTIR. The effect of important factors, such as ionic strength, pH, and polymer concentration on the phase transition behavior of temperature‐sensitive polymers, were investigated by cloud point measurements. The resulting thermosensitive polymers were used for the entrapment of a narcotic antagonist drug, naltrexone, as the model drug. The loading efficiency and drug release behavior of naltrexone‐loaded hydrogels were investigated. The naltrexone loaded thermosensitive polymers were able to sustain the release of naltrexone for different periods of time, depending on the polymer composition, and concentration. In vitro release studies showed that these thermosensitive polymers are able to deliver naltrexone in biologically active forms at a controlled rate for 3–8 weeks. Copyright © 2009 John Wiley & Sons, Ltd.     

导电高分子及其纳米复合材料的热电性质

与无机热电材料相比, 有机热电材料具有资源丰富、 成本低、 质量轻、 柔韧性好及热导率低等优点, 成为热电研究领域关注的热点. 理论和实验结果表明, 低维化和小尺度化是热电材料研究和开发的发展方向. 本文对低维有机热电材料的合成、 器件组装及热电性质的影响因素等进行简要评述, 并对低维有机热电材料的研究方向进行了讨论.     

液晶金属配位聚合物的合成及性能

基于国内外最新研究文献 ,系统论述了近年来液晶金属配位聚合物的合成方法、液晶行为及应用前景。指出液晶金属配位聚合物的合成方法可归纳为直接配位法、单体配位法、交联配位法和聚合物反应法四种。液晶金属配位聚合物一般呈现热致液晶行为 ,显示稳定的向列液晶相或近晶液晶相。有些金属配位聚合物还呈现互变性近晶态或单变液晶性。液晶金属配位聚合物具有金属的特殊性质 ,是一种新型高性能磁导、电导和光导材料 ,可望应用于液晶显示材料、磁性信息储存薄膜材料、润滑剂和各向异性催化剂等。     

Recent advances of CuAAC click reaction in building cyclic polymer

Cyclic polymers have attracted more and more attentions in recent years because of their unique topological structures and characteristic properties in both solution and bulk state. There are relatively few reports on cyclic polymers, partly because of the more demanding synthetic procedures. In recent years, “click” reaction, especially Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC), has been widely utilized in the synthesis of cyclic polymer materials because of its high efficiency and low susceptibility to side reactions. In this review, we will focus on three aspects: (1) Constructions of monocyclic polymer using CuAAC “click” chemistry; (2) Formation of complex cyclic polymer topologies through CuAAC reactions; (3) Using CuAAC “click” reaction in the precise synthesis of molecularly defined macrocycles. We believe that the CuAAC click reaction is playing an important role in the design and synthesis of functional cyclic polymers.     

Specificity of the application of disperse and fibrous fillers in heterophase polymer materials

The mechanism of the reinforcing effect of fillers in polymer composition is studied and the relation between the properties and structure of materials is established. It is shown that, upon the addition of even a small amount of filler, properties of polymers change markedly due to intermolecular interactions. Variations in the composition of filled polymers and conditions of their preparation make it possibly to regulate properties of polymers within noticeably wide ranges. Specific features of polymer compositions filled with polymer fibers, the effect of fiber length, and the degree of orientation on the strength of composition are considered. For crosslinked epoxy urethane polymers, the effect of glass and polycaproamide (capron) fibers on the mechanical properties of polymer clutches in glassy and rubbery states is studied. The possibility to realize the shape memory effect for shrinkable filled polymer clutches is demonstrated.     

石墨烯化聚合物:一种兼具电子和离子传输通道的三维富碳高分子能源材料

近年来,用于电化学能源存储和转化的石墨烯材料,得到了研究者们越来越多的关注。但是,这些石墨烯材料不同于严格定义的单原子碳层结构,往往具有孔洞、杂原子和化学官能团等缺陷结构。由于制备方法的不同,缺陷结构各不相同,其电化学性能也表现各异。结构分析表明,这类材料是由类似石墨烯片段的单元与聚合物链共价连接而成,使其具有石墨烯和聚合物的双重特性,我们称之为石墨烯化聚合物。由小分子通过自下而上的方法制备的多孔聚合物,也可以通过进一步热交联等方法,使其形成包含石墨烯片段单元与聚合物链的化学结构。这些材料与石墨烯衍生材料一起组成了石墨烯化聚合物的整个谱系;这个谱系涵盖了由聚合物到石墨烯的过渡区。更重要的是,这类材料特殊的结构与性质,使其成为一种兼具电子和离子传输通道的三维富碳高分子材料,非常适合作为电极材料应用于电化学能源存储和转化,这为我们深入研究储能器件中电极材料的结构与性能的相关关系提供了很好的材料平台。     

高分子材料的微波辅助合成研究进展

微波加热以其省时、高效、清洁环保的显著优势而使微波辅助合成成为一种广受欢迎的合成技术。高分子材料的传统合成反应时间长、耗能大。将微波辐射应用于高分子材料的合成可缩短反应时间、降低反应能耗,已成为有机合成领域的研究热点。本文简要综述了微波辅助合成技术在工程材料高分子聚酰胺、聚酰亚胺、聚丙烯酸苄基酯以及在医用功能高分子、吸附功能高分子、导电功能高分子和光学功能高分子合成中的研究进展,并展望了微波辅助合成在高分子材料合成中的发展前景。