通过微观形态控制降低导电高分子复合材料逾渗值的研究进展

降低复合型导电高分子材料的逾渗值是实现材料低成本化和高性能化的关键.这方面的研究一直以来都受到学术界和产业界的广泛关注.本文介绍了近年来通过微观形态控制手段降低导电高分子复合材料逾渗值的研究状况.文章将现有的形态控制方法归纳为双逾渗方法、隔离分布方法、原位微纤方法、自组装方法等七大类,并从微观形态实现机理、形态与电性能关系、应用前景等方面对这些方法进行了讨论.此外,本文还对该研究领域未来发展趋势作了展望.     

导电高分子纳米复合材料

导电高分子纳米复合材料是纳米材料研究中一个重要部分。着重综述了导电高分子无机纳米复合材料在合成技术、材料性质和各领域中应用的最新研究进展。     

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.     

导电型高分子/碳纳米管复合材料研究

介绍了作者课题组近年来在导电型高分子/碳纳米管(CNT)复合材料研究中若干有代表性的工作,我们从设计多相多组分体系角度出发,通过向单一高分子/CNT体系中添加包括无机粉体、有机高分子和第二种导电介质等第三组分来调控CNT在体系中的分布状态,以期建立提高复合材料的导电性能的技术方法,并研究了添加第三组分引致材料导电性能提...     

智能高分子材料

本文介绍了形状记忆树脂、高分子凝胶、本征导电聚合物、高分子复合材料、高分子薄膜、超分子聚合物、液晶聚合物等智能高分子材料的一般概念及其应用的一些方面。     

高分子/石墨复合材料的制备与导电性能的研究进展

介绍了近年来高分子/石墨复合材料制备方法和导电机理的研究进展。通过氧化、插层以及插层后加热可以在石墨碳层上引入极性基团,提高其比表面积,有利于高分子进行插层。用处理后比表面积高的石墨制备复合材料可以降低材料的渗滤值,提高材料的导电性能。复合材料的导电机理可以用渗滤理论来解释。     

碳纳米管/高分子复合导电材料的研究进展

从碳纳米管的电性质出发,对以它为填料的导电性复合材料的制备方法和研究进展进行了综述,同时简单介绍了导电性复合材料电性质转变现象的理论分析模型,最后对碳纳米管/高分子复合导电材料的研究前景作了一定探讨。     

全钒液流电池用导电高分子材料集流体的研究

以炭黑、石墨、碳纤维等炭系与基体树脂复合改性得到体积电阻率小于0.1的导电高分子材料.研究了不同复合体系及不同配方的复合材料的导电性能,其中尤以SIS/PP体系中碳纤维占填料量32.5%的材料导电率高、力学性能和加工性能良好,并与石墨毡有较好的粘接性.选用该体系作为钒电池集流板,考察了电池性能,研究结果表明,导电高分子材料可以作为钒电池集流体材料,并在钒电池中具有良好的应用前景.     

高分子基导电复合材料气敏响应机理研究

高分子基气敏导电材料是近年来发展起来的一种新型功能高分子复合材料.本文介绍了以炭黑(CB)为导电填充剂的复合传感材料的气敏响应机理的体积膨胀模型、结晶模型和氢键模型,并讨论了逾渗阀值、CB及聚合物微观结构与性能、以及CB与聚合物和溶剂三者之间相互作用等因素对该类材料气敏响应性的影响.     

聚合物固体电解质研究进展

本文概述近十几年来聚合物固体电解质材料开发研究的状况,包括线型高分子、为改进性能而发展起来的枝型、梳型及交联型高分子,并对高分子与金属盐络合的离子聚合物结构和性能作了描述。阐述了高分子固体电解质的导电行为、导电模型及导电机理。对聚合物固体电解质的各种应用作了介绍并简要讨论了高分子固体电解质的发展趋向及前景。     

研制碳团簇型微波隐身材料的参考准则

本文建议研制单层和双层碳团簇型微波隐身材料的参考准则。根据这些参考准则，我们已制出性能优异的微波隐身材料，微波反射率在８－１２．４ＧＨＺ内达－３０ｄＢ．理论计算表明，这是由于三类平面碳团簇的转动或振转能级间跃迁所致。     

电磁屏蔽材料的研究进展

介绍了电磁屏蔽材料在军用和民用领域的重要性;简要阐述了电磁屏蔽的机理;综述了4种不同电磁屏蔽材料的优缺点以及研究现状,分别为金属型、表面导电型、填充复合型和本征型导电聚合物电磁屏蔽材料;分析并提出了3种提高电磁屏蔽效能的方式,分别为多孔结构设计、多层结构设计、复合填料优化.     

How Low Can You Go? Low Densities of Poly(ethylene glycol) Surfactants Attract Stealth Proteins

It is now well‐established that the surface chemistry and “stealth” surface functionalities such as poly(ethylene glycol) (PEG) chains of nanocarriers play an important role to decrease unspecific protein adsorption of opsonizing proteins, to increase the enrichment of specific stealth proteins, and to prolong the circulation times of the nanocarriers. At the same time, PEG chains are used to provide colloidal stability for the nanoparticles. However, it is not clear how the chain length and density influence the unspecific and specific protein adsorption keeping at the same time the stability of the nanoparticles in a biological environment. Therefore, this study aims at characterizing the protein adsorption patterns depending on PEG chain length and density to define limits for the amount of PEG needed for a stealth effect by selective protein adsorption as well as colloidal stability during cell experiments. PEG chains are introduced using the PEGylated Lutensol AT surfactants, which allow easy modification of the nanoparticle surface. These findings indicate that a specific enrichment of stealth proteins already occurs at low PEG concentrations; for the decrease of unspecific protein adsorption and finally the colloidal stability a full surface coverage is advised.     

近红外激光防护染料

以激光防护和隐身材料为需求背景，概述了菁类染料(含多次甲基菁染料、方酸菁和克酮酸菁染料、薁染料)、酞菁类染料(含普通酞菁和萘酞菁)、金属络合物染料、醌型染料、偶氮染料、游离基型染料、芳甲烷型染料、苝类染料等近红外吸? 杖玖系难芯孔纯黾敖埂? $601$ADuetotherequirementofnear-infraredlaserprotectivedyesandlaserstealthmaterials,thisreviewfocusedontheresearchprogressofnear-infraredabsorbingdyes,andsomesuggestionswereputforwardonthefutureresearch.Someofthemostimportanttechnicalrequiremnetsforlaser-protectivedyeswithintheplasticareasfollows:sharpabsorptionbandsatspecificwavelengthscorrespondingtolaseremission,excellentlightfastness,robustthermalandchemicalstability,stabilitytoambientconditions,highopticaldensityandscotopicluminoustransmission,goodsolubilityinplasticandlowtoxicity.Thisreviewpaidattentiontothepropertiessuchasthemaximumabsorptionwavelengthandtheabsorptionintense,attentionhadbeendirectedtowardseighttypesnear-infrareddyes:cyaninedyeswhichincludedpolymethinedyesandsquaryliumorcroconiumdyes,phthalocyaninesandnaphthalocyanines,metalcomplexdyes,quinonedyes,azodyes,radicaldyes,multiphenylmethanedyesandperylenedyes.Otherkindsofnear-infrareddyeswerealsomentioned,suchasaromaticannulenes,planescontainignso-callednonbenzenoidaromaticrings,cycliccross-conjugatedhydrocarbonshavinginsertedp-quiniodring,fluorenyliumdyeswithinorganicanions,donor-acceptorcyclophanes,tetrapyrazinoporphyrazinesandpentaazadentateexpandedporphyrinsetal.Allofthedyesmentionedabovehadsomegoodpropertiesforuseasthenear-infraredlaserprotectivedyesandlaserstealthmaterials,buttherealsoexisteddefectsineverykindofdyes.     

太赫兹隐身及屏蔽材料研究进展

阐述了太赫兹隐身和屏蔽性能分析的计算模型, 并对几种典型的太赫兹隐身和屏蔽材料进行了综述和介绍, 指出了当前研究存在的问题以及今后的发展方向.     

Poly(ethylene glycol) in Drug Delivery: Pros and Cons as Well as Potential Alternatives

Poly(ethylene glycol) (PEG) is the most used polymer and also the gold standard for stealth polymers in the emerging field of polymer‐based drug delivery. The properties that account for the overwhelming use of PEG in biomedical applications are outlined in this Review. The first approved PEGylated products have already been on the market for 20 years. A vast amount of clinical experience has since been gained with this polymer—not only benefits, but possible side effects and complications have also been found. The areas that might need consideration and more intensive and careful examination can be divided into the following categories: hypersensitivity, unexpected changes in pharmacokinetic behavior, toxic side products, and an antagonism arising from the easy degradation of the polymer under mechanical stress as a result of its ether structure and its non‐biodegradability, as well as the resulting possible accumulation in the body. These possible side effects will be discussed in this Review and alternative polymers will be evaluated.     

Stealth Liposomes (PEGylated) Containing an Anticancer Drug Camptothecin: In Vitro Characterization and In Vivo Pharmacokinetic and Tissue Distribution Study

Numerous attempts to overcome the poor water solubility of cam ptothecin (CPT) by various nano drug delivery systems are described in various sources in the literature. However, the results of these approaches may be hampered by the incomplete separation of free CPT from the formulations, and this issue has not been investigated in detail. This study aimed to promote the solubility and continuous delivery of CPT by developing long-lasting liposomes using various weights (M.W. 2000 and 5000 Daltons) of the hydrophilic polymer polyethylene glycol (PEG). Conventional and PEGylated liposomes containing CPT were formulated via the lipid film hydration method (solvent evaporation) using a rotary flash evaporator after optimising various formulation parameters. The following physicochemical characteristics were investigated: surface morphology, particle size, encapsulation efficiency, in vitro release, and formulation stability. Different molecular weights of PEG were used to improve the encapsulation efficiency and particle size. The stealth liposomes prepared with PEG₅₀₀₀ were discrete in shape and with a higher encapsulation efficiency (83 ± 0.4%) and a prolonged rate of drug release (32.2% in 9 h) compared with conventional liposomes (64.8 ± 0.8% and 52.4%, respectively) and stealth liposomes containing PEG₂₀₀₀ (79.00 ± 0.4% and 45.3%, respectively). Furthermore, the stealth liposomes prepared with PEG₅₀₀₀ were highly stable at refrigeration temperature. Significant changes were observed using various pharmacokinetic parameters (mean residence time (MRT), half-life, elimination rate, volume of distribution, clearance, and area under the curve) of stealth liposomes containing PEG₂₀₀₀ and PEG₅₀₀₀ compared with conventional liposomes. The stealth liposomes prepared with PEG₅₀₀₀ showed promising results with a slow rate of release over a long period compared with conventional liposomes and liposomes prepared with PEG₂₀₀₀, with altered tissue distribution and pharmacokinetic parameters.     

含偶氮苯光学活性侧基聚合物研究进展

综述了含偶氮苯光学活性侧基聚合物近年来的发展概况 ,介绍了多种聚合体系的类型。由于偶氮苯光于活性侧基的存在 ,使得这些聚合物具有光致变色性、非线性光学活性、光学各向异性等光学性能 ,在光信息存储材料、非线性光学材料、液晶材料、光电子器件、生物分子活性光调控、纳米技术等诸多领域都有广泛的应用。     

铝镧共掺杂的氧化锌红外隐身涂料在帐篷织物上的应用

以水性聚氨酯为粘合剂,掺杂Al和La的ZnO为填料,配以其它助剂制成了红外隐身涂料,应用在帐篷织物表面,探究涂层厚度以及填料含量对红外发射率的影响,并研究了导热系数和红外隐身性能之间的关系。 研究发现,涂层厚度和填料含量对涂层织物的红外发射率有着显著的影响。 当填料质量分数为70%时,得到的帐篷涂层织物的红外发射率可降至0.622,调节填料含量和涂层厚度,可以的得到红外发射率在0.622~0.932之间的帐篷涂层织物。 此外,发现导热系数对红外隐身性能也有一定的影响,红外隐身性能随着导热系数的增加而提高。 通过调节填料含量和涂层厚度制作不同红外发射率的涂层帐篷织物,放在不同背景下拍摄红外热成像图,发现涂层在不同的环境中均具有良好的伪装能力。