聚合物微纳米管的制备技术

由于聚合物微纳米管独特的一维中空结构和性能多样性,在分离、电子器件、催化剂负载、药物释放等方面具有广泛的应用前景,本文结合最新的研究进展,总结了聚合物微纳米管的制备方法,并重点介绍了硬模板法、软模板法和无模板法的特点。     

导电聚合物微米/纳米管的研究进展

介绍了模板及非模板法制备导电聚合物微米 /纳米管的基本合成方法 :详细地分析了影响导电聚合物微米 /纳米管形成的因素 ;对导电聚合物微米 /纳米管的特性及影响因素进行了讨论。     

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。     

模板法合成纳米结构材料

模板法（包括硬模板和软模板法）是制备纳米结构材料的常用方法,可用来制备多种物质的各种形状（如：球形粒子、一维纳米棒、纳米线、纳米管以及二维有序阵列等）的纳米结构,近年来关于这一领域的研究较为活跃。本文介绍了近年来利用氧化铝、二氧化硅、碳纳米管、表面活性剂、聚合物、生物分子等作模板制备多种物质的纳米结构材料的一些进展。     

多孔模板法制备聚乙撑二氧噻吩纳米管光电性能的研究

采用单体聚合-溶液浸润-聚合物成管同时进行的方法,在氧化铝多孔模板(AAO)中制备了聚乙撑二氧噻吩(PEDOT)纳米管.通过形貌分析推断PEDOT纳米管在孔道中的生长包括两个过程:首先是聚合物溶液浸润整个孔道;然后是聚合过程中生成的阳离子自由基和掺杂态的PEDOT由于带正电荷而在孔道壁产生"钉扎"效应.XRD分析显示,在孔道内生成的PEDOT分子链具有一定的取向性.进一步研究表明,聚合物的吸附及单体聚合后的吸附,在模板壁导致不同的分子链排列,使PEDOT纳米管分子排列有序性受到影响.采用四探针和扫描隧道显微镜(STM)方法研究了纳米管光电性能.     

模板法制备无机纳米材料的研究进展

模板法在无机纳米材料的制备过程中能够有效地控制形貌、粒径和结构,已成为合成无机纳米材料的前沿方法。综述了模板法制备无机纳米材料的研究进展,主要介绍了硬模板剂(多孔阳极氧化铝、介孔碳)和软模板剂(高分子聚合物、生物高分子)的制备及其应用,结合模板法的作用机制,重点论述了不同种类的模板剂在无机纳米材料制备过程中对于形貌的影响。并对模板法制备无机纳米材料的前景和现存问题进行了总结。参考文献35篇。     

模板法制备聚乙烯咔唑及其复合物纳米管有序阵列

近十几年来,纳米管引起了人们越来越多的关注,不仅仅是由于它独特的性质,也因为它们在电、磁以及光电器件上具有广泛的应用前景。纳米管的制备方法大体上分为两种:自组装法[1￣3]和模板法[4￣7]。尽管自组装法已成功地制得了一些纳米管,但由于它对构造纳米管的材料有着较严格的     

低频交流电沉积金纳米线阵列的AFM研究

迄今,人们已采用许多方法制备纳米材料,如刻蚀技术、化学法和模板法等［1]．其中,引起科学界广泛兴趣的模板法,在合成有序纳米材料上占有极其重要的地位．常用的模板有两种,一种是有序孔洞阳极氧化铝（Anodic Aluminum Oxide,AAO）模板[2],另一种是含有孔洞无序分布的高分子模板．AAO模板具有耐高温,绝缘性好,孔洞分布均匀有序,而且大小可控等特点［3]．可以利用 AAO模板来制备各种纳米纤维和纳米管,如导电聚合物［4]、金属［5]、半导体［6]、碳［7]和其它一些材料．由于纳米材料的应用具有广阔的前景,如光催化、电化学、酶固定等方面,因而不同材料纳米线的制备备受关     

化学修饰阳极氧化铝模板法合成小尺寸聚苯胺纳米线

利用表面活性剂对阳极氧化铝(AAO)模板进行化学修饰，发展了模板合成法，从而得到更小尺寸的聚苯胺纳米管、线.在表面活性剂十八烷基脂肪酸(R18)修饰下，在14 nm孔径的AAO模板中合成7 nm的纳米线.对不同表面活性剂的比较后发现,通过改变修饰表面活性剂上烷基链长可以对所制备的聚合物纳米管、线的直径进行调控.     

复合分子印迹固相萃取柱及其制备方法与应用

正公布号:CN105032381A公布日:2015.11.11申请人:中国农业科学院农业质量标准与检测技术研究所摘要:本发明公开了复合分子印迹固相萃取柱的制备方法,包括以下步骤:(1)以三嗪类农药为模板分子制备分子印迹聚合物A;(2)以磺酰脲类农药为模板分子制备分子印迹聚合物B;(3)制备复合分子印迹固相萃取柱。本发明的复合     

Reactive Template Synthesis of Polypyrrole Nanotubes for Fabricating Metal/Conducting Polymer Nanocomposites

Unique nanocomposites of polypyrrole/Au and polypyrrole/Pt hybrid nanotubes are synthesized employing polypyrrole (PPy) nanotubes as an advanced support by solution reduction. The conducting polymer PPy nanotubes are fabricated by using pre‐prepared MnO₂ nanowires as the reactive templates. MnO₂ nanowires induce the 1D polymerization of pyrrole monomers and the simultaneous dissolution of the templates affords the hollow tube‐like structure. The loading content of metal nanoparticles in the nanocomposites could be adjusted by simply changing the amount of metal precursors. This work provides an efficient approach to fabricate an important kind of metal/conducting polymer hybrid nanotubes that are potentially useful for electrocatalyst and sensor materials.     

Preparation of Carbon Nanotubes by the Catalysis of Polymer Metal Complex on Porous Al203 Matrix

At present, synthesis of carbon nanotubes (CNTs) is normally conducted on a vapor-to-solid interface at ca. 500-3500℃ via various vapor phase methods, such as are discharge, laser ablation, catalytic pyrolysis and chemical vapor deposition, etc.1-2 Recently, channel materials (such as channels of alumina and of AlPO4-5 zeolite) 3 have been utilized as solid-state templates to grow CNTs inside the channel. Here we described a novel method to prepare the carbon nanotubes based on the decomposition of C2H2 gas on the Co-Ni catalyst anchored by polymer complex on the porous A12O3 matrix. The degree of graphitization of synthesized CNTs and catalysts are of great interest.     

Free-standing, erect ultrahigh-aspect-ratio polymer nanopillar and nanotube ensembles

Free-standing polymer (poly(methyl methacrylate) or cyclic olefin copolymer) nanopillar and nanotube ensembles with previously unreported, ultrahigh aspect ratios (300 to >1600) were fabricated via anodic aluminum oxide (AAO) template-based methods that utilize a dilute, aqueous H3PO4 template etchant followed by freeze drying removal of the aqueous medium. Good replication of the AAO template by either solutions of the polymeric materials or molten polymer was achieved by using ultrasonic degassing and vacuum conditions. Classical surface wetting and viscoelastic fluid rheology theories were applied to explain the formation of polymer nanopillars and nanotubes in the aluminum oxide templates. The utilization of dilute H3PO4 for etching the AAO template and freeze-drying removal of the environmental liquid allows for the preparation of free-standing, erect, and ordered polymeric nanopillars or nanotubes that show much promise for use in biological microelectromechanical systems that target biological analyses.     

Template Synthesis of Nano-structured Materials for Electrochemical Applications

As an important preparation method of nano-structured materials, template synthesis^[1] attracted great interests in recent years. Different kinds of template such as anodic porous alumina, polymer and nano-channel glass templates have been widely studied. Compared with other templates, the size of holes in the porous alumina template can be easily controlled by properly adjusting the condition of anodization. In addition, Nano-structured material prepared from the template also provides an ideal system^[2] to investigate the effects of size of materials toward electrode's performance. In this paper, various nano-structured materials such as spinel LiMn₂O₄ and carbon nanotubes by using porous alumina template have been prepared and characterized.     

Preparation and characterization of multilayered polymer nanotube dispersions

Despite considerable efforts to synthesize nanotubes using porous alumina or polycarbonate membrane templates, few studies have addressed the resulting nanotube dispersion. We prepared dispersions of multilayered polyethylenimine/maleic anhydride alternating copolymer (PEI/MAAC) nanotubes synthesized with porous alumina templates. After mechanical polishing to remove the residual polymer surface layer from templates and subsequent template dissolution, the multilayered PEI/MAAC nanotubes were easily dispersed in water at neutral pH by polyelectrolyte adsorption, producing nanotube dispersions that were stable for at least 3 months. We characterized the dispersions using phase-contrast optical microscopy, electro-optics, electrophoresis, and viscometry to help understand their colloidal properties in the dilute and semidilute regimes. The dispersions were resistant to salt-induced aggregation up to at least 1 mM NaCl and were optically anisotropic when subjected to an electric field or flow. Interestingly, the electrophoretic mobility of polystyrene sulfonate (PSS)-stabilized nanotubes increases with increasing ionic strength, because of the high surface charge and softness of the adsorbed polyelectrolyte. Furthermore, unlike many rod-like colloid systems, the polymer nanotube dispersion has low viscosity because of weak rotary Brownian motions and strong tendency to shear thinning. At the high shear rates achieved in capillary viscometry experiments, however, we observed a slight shear thickening, which can be attributed to transient hydrocluster formation.     

Tea‐Bag‐Like Polymer Nanoreactors Filled with Gold Nanoparticles

Gold‐containing polymer nanotubes, which showed both catalytic activity and resistance to leaching, were prepared by the “tubes by fiber templates” (TUFT) process. For this purpose, electrospun polymer nonwovens with incorporated poly(L ‐lactide)‐stabilized gold nanoparticles were coated with poly(p‐xylylene) by the chemical vapor deposition process, and then the inner fiber templates were removed. The resulting polymer tubes carried encapsulated gold nanoparticles which were shown to be immobilized and featured pronounced catalytic activity towards the hydrolytic oxidation of dimethylphenylsilane and the alcoholysis of dimethylphenylsilane with n‐butanol. The macroscopic nonwovens could be used as tea‐bag‐like catalyst systems and showed excellent reusability.     

Preparation of poly 2-hydroxyethyl methacrylate functionalized carbon nanotubes as novel biomaterial nanocomposites

We report a simple method for the functionalization of multi-walled carbon nanotubes (MWNTs) with a biomedically important polymer, poly(2-hydroxyethyl methacrylate) (poly(HEMA)), by chemical grafting of HEMA monomer followed by free radical polymerization. The nanotubes were first oxidized with a mixture of conc. nitric acid and sulfuric acid (1:3), in order to obtain carboxylic acid functionalized MWNTs. Then the grafting of HEMA on to the surface of MWNTs was carried by chemical functionalization of HEMA with acid chloride-bound nanotubes by esterification reaction. FT-IR was used to identify functionalization of -COOH and HEMA groups attached to the surface of the nanotubes. The presence of poly(HEMA) on the nanotubes were confirmed by FESEM, TEM, and TGA analyses. Additionally, the dispersibility of the polymer functionalized nanotubes in methanol was also demonstrated. Considering the biomedical importance of poly(HEMA) and the recent successful in vivo studies on CNTs, in future, these materials are expected to be useful in the pharmaceutical industry as novel biomaterials composites with potential applications in drug delivery.     

聚合物辅助碳纳米管定向定位排列

探讨了聚合物对碳纳米管的不同表面修饰作用,总结了聚合物对碳纳米管的共价与非共价修饰方法,修饰后的碳纳米管在水溶液或不同极性有机溶剂、聚合物本体中的分散性得到了改善,更为碳纳米管的阵列化提供了前提.以碳纳米管的后排列为中心,主要综述了聚合物辅助下的碳纳米管垂直和水平方向上的定向排列方法,及近年来碳纳米管阵列化的研究进展,阐述了聚合物对碳纳米管的表面修饰及辅助碳纳米管实现阵列化的重要作用,提出了利用聚合物体系的自组织特性诱导碳纳米管自组装阵列化可以为实现单根碳纳米管的定向定位控制及纳米尺度功能器件的制备提供更多的可能.     

Confinement Effects on the Crystallization of Poly(ethylene oxide) Nanotubes

In this work, we show the effects of nanoconfinement on the crystallization of poly(ethylene oxide) (PEO) nanotubes embedded in anodized aluminum oxide (AAO) templates. The morphological characteristics of the hollow 1D PEO nanostructures were evaluated by scanning electron microscopy (SEM). The crystallization of the PEO nanostructures and bulk was studied with differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). The crystallization of PEO nanotubes studied by DSC is strongly influenced by the confinement showing a strong reduction in the crystallization temperature of the polymer. X-ray diffraction (XRD) experiments confirmed the isothermal crystallization results obtained by DSC, and studies carried out at low temperatures showed the absence of crystallites oriented with the extended chains perpendicular to the pore wall within the PEO nanotubes, which has been shown to be the typical crystal orientation for one-dimensional polymer nanostructures. In contrast, only planes oriented 33, 45, and 90° with respect to the plane (120) are arranged parallel to the pore's main axis, indicating preferential crystal growth in the direction of the radial component. Calculations based on classical nucleation theory suggest that heterogeneous nucleation prevails in the bulk PEO whereas for the PEO nanotubes a surface nucleation mechanism is more consistent with the obtained results.     

Persistence length control of the polyelectrolyte layer-by-layer self-assembly on carbon nanotubes

We have studied layer-by-layer polyelectrolyte self-assembly on pristine individual single-wall carbon nanotubes as a function of solution ionic strength. We report the existence of an ionic strength threshold for the deposition, below which the majority of nanotubes remain uncoated. Once the ionic strength reaches the threshold value, the majority of the individual nanotubes become coated with polyelectrolytes. Our results indicate that the self-assembly process likely involves wrapping of polymer chains around nanotubes and that the polymer chain's ability to bend in order to accommodate the nanotube curvature is one of the critical parameters controlling layer-by-layer electrostatic self-assembly on these one-dimensional templates.