共查询到20条相似文献,搜索用时 225 毫秒
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银纳米粒子由于其特殊的物理化学性质而被广泛应用,但其易团聚,影响实际使用效果。银纳米粒子可被负载到稳定载体上,获得具有优异性能的纳米复合材料,克服了团聚等缺限,大大改善应用效果和效率。采用静电纺丝技术制备银修饰纳米复合纤维材料是其中一种有效的方法,近年来在复合材料制备领域受到了广泛关注。本文综述了最近几年关于静电纺丝制备负载银纳米颗粒纤维复合材料及其应用的研究进展,重点介绍了静电纺丝制备负载银纳米纤维过程中纳米银的生成和负载方法,总结了有机主体和无机主体两种纺丝纤维的制备研究进展,详细介绍了负载银纺丝纤维在几个重要领域的应用及研究方向。 相似文献
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静电纺丝是一种简单、实用的制造纳米纤维的技术,所需设备少,易于大规模生产。本文主要从催化剂、固体聚电解质膜及膜电极三方面阐述了静电纺丝技术在低温燃料电池中的应用。静电纺丝制得的一维纳米线电催化剂具有稳定的循环性能、优异的传质能力及较低的成本;制备的固体聚电解质膜主要包括Nafion复合膜、阻醇膜及耐温膜,其性能相对于传统的Nafion膜得到了进一步提升,而且,通过采用静电纺丝技术,使膜电极结构得到了优化。最后,对静电纺丝技术在低温燃料电池应用过程中可能存在的问题及其未来的发展趋势进行了展望。 相似文献
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采用新型流动水浴收集方式制备出连续单向排列的静电纺聚丙烯腈(PAN)纳米初生纤维,收集静电纺丝不同阶段的静电纺PAN纳米纤维,并在热水中进行后牵伸,使其伸长至原长的2倍、3倍.通过扫描电子显微镜(SEM)、广角X射线衍射(WAXD)等方法对静电纺丝过程不同阶段的PAN纳米纤维的形貌、直径、致密性、晶态结构及取向进行了表征.研究表明,(1)在静电纺丝过程中PAN纺丝液射流受到牵伸作用,静电纺PAN纳米纤维的晶态结构形成并逐渐完善.纳米纤维的直径随着静电纺丝过程逐渐减小(从664 nm减小至353 nm),结晶度从42.55%增加至47.76%,晶区取向由37.48%提高至43.93%.纳米纤维致密性也逐渐提高(密度由1.1917 g/cm3增加至1.1943 g/cm3).(2)静电纺丝过程进入PAN射流溶剂含量较低的阶段后,继续通过静电纺丝过程提高纳米初生纤维晶态结构及取向的效果很有限,而通过热水后牵伸过程可进一步使晶态结构及取向得到有效果的完善.研究同时发现,静电纺初生纤维的晶态结构及取向与其在热水牵伸过程中的进一步完善具有相关性. 相似文献
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Stability analysis for multi-jets electrospinning process modified with a cylindrical electrode 总被引:2,自引:0,他引:2
Nanosize fibers were fabricated using an extra-cylindrical electrode connected with single and multiple nozzles of an electrospinning process to stabilize the initial spun jets. To predict stability of spun jets, an electric field concentration factor (EFCF), which could be defined as a degree of a convergence of jets to a spinning axis, was introduced. The proposed parameter EFCF is utilized for the comparison of the experimental results for single and multi-nozzles electrospinning process. To consider the mass productivity of the multi-nozzles electrospinning supported by an auxiliary electrode, the weight of nanofibers that were spun to a rectangular shape target plate during 40 min was measured. The result indicates that the modified electrospinning technique shows a possibility as a useful method for increasing the production rate of nanofiber manufacturing. 相似文献
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Electrospinning is a versatile and flexible technique for the preparation of ultrafine fibers. The present study aims to provide a comprehensive overview of electrospinning, as a complex technique, its evolution toward the high-throughput techniques, including the basic principles, parameters influencing the fibers production process, methods applied to solve the alignment difficulties, commonly used polymers and solvents, and the applications of the electrospun materials. We begin with an insight into the history of electrospinning, followed by its theoretical background and typical apparatus. Then, its renaissance over the past two decades as a powerful technology for the production of nanofibers suitable for industrial scale is presented. Afterward, we briefly discuss the applications of electrospun fibers, including use in different fields of industry, energy harvesting/conversion/storage, photonic and electronic devices, as well as biomedical applications. In the end, we also offer perspectives on the challenges and new directions for developments in electrospinning. 相似文献
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Jorge Ivn Castro Manuel N. Chaur Carlos Humberto Valencia Llano Mayra Eliana Valencia Zapata Jos Herminsul Mina Hernandez Carlos David Grande-Tovar 《Molecules (Basel, Switzerland)》2021,26(16)
In recent decades, the number of patients requiring biocompatible and resistant implants that differ from conventional alternatives dramatically increased. Among the most promising are the nanocomposites of biopolymers and nanomaterials, which pretend to combine the biocompatibility of biopolymers with the resistance of nanomaterials. However, few studies have focused on the in vivo study of the biocompatibility of these materials. The electrospinning process is a technique that produces continuous fibers through the action of an electric field imposed on a polymer solution. However, to date, there are no reports of chitosan (CS) and polyvinyl alcohol (PVA) electrospinning with carbon nano-onions (CNO) for in vivo implantations, which could generate a resistant and biocompatible material. In this work, we describe the synthesis by the electrospinning method of four different nanofibrous membranes of chitosan (CS)/(PVA)/oxidized carbon nano-onions (ox-CNO) and the subdermal implantations after 90 days in Wistar rats. The results of the morphology studies demonstrated that the electrospun nanofibers were continuous with narrow diameters (between 102.1 nm ± 12.9 nm and 147.8 nm ± 29.4 nm). The CS amount added was critical for the diameters used and the successful electrospinning procedure, while the ox-CNO amount did not affect the process. The crystallinity index was increased with the ox-CNO introduction (from 0.85% to 12.5%), demonstrating the reinforcing effect of the nanomaterial. Thermal degradation analysis also exhibited reinforcement effects according to the DSC and TGA analysis, with the higher ox-CNO content. The biocompatibility of the nanofibers was comparable with the porcine collagen, as evidenced by the subdermal implantations in biological models. In summary, all the nanofibers were reabsorbed without a severe immune response, indicating the usefulness of the electrospun nanocomposites in biomedical applications. 相似文献
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提出一种实心针静电纺丝方法, 采用实心针作为静电发射极, 并将其置于由绝缘材料制成的导液棒轴心, 导液棒处于储液盒底部的圆锥沉头通孔内部并可以做升降运动以控制供液量, 需要时还可以起到通流的作用, 有效地解决了多针头静电纺丝堵塞和无针头静电纺丝开放式供液的问题. 利用COMSOL有限元分析软件对影响场强大小及分布的各参数进行场强模拟, 研究增大场强并减小边缘效应的改进方法, 并采用研发的不完全齿轮横动机构纺丝头做往复横动进行纺丝实验, 验证了实心针静电纺丝装置有效降低了能耗和边缘效应, 避免了针头堵塞及溶剂挥发问题. 相似文献
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This review deals with electrospun nanofibers and their applications in several fields. Nanofibers have mainly been produced via electrospinning technique due to the simple, cost-effective, and versatile setup. Electrospinning is defined as a process, which produces fibers from its polymer solutions under exposure of high electric field voltage. The technique needs optimization of several parameters such solution, processing and ambient parameters to refine nanofiber morphology, diameter and porosity. The basic technique has been modified to produce composite fibers and to increase production capacity. Nanofiber characterization methods are summarized with examples. The relation between electrospinning and electrospraying is discussed. Nanofibers have the ability to form highly porous mesh with large surface to volume ratio enhancing its performance for various applications such as water filtration, tissue engineering scaffold, wounds, fiber composites, drug release and protective clothes. Single nanofibers could potentially be used as soft microrobots for drug delivery. Finally, results from modeling and simulations are illustrated. 相似文献
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Raimund Jaeger Michel M. Bergshoef Cristina Martín I. Batlle Holger Schnherr G. Julius Vancso 《Macromolecular Symposia》1998,127(1):141-150
The electrospinning technique was used to spin ultra-thin fibers from several polymer/solvent systems. The diameter of the electrospun fibers ranged from 16 nm to 2 μm. The morphology of these fibers was investigated with an atomic force microscope (AFM) and an optical microscope. Polyethylene oxide) (PEO) dissolved in water or chloroform was studied in greater detail. PEO fibers spun from aqueous solution show a “beads on a string” morphology. An AFM study showed that the surface of these fibers is highly ordered. The “beads on a string” morphology can be avoided if PEO is spun from solution in chloroform; the resulting fibers show a lamellar morphology. Polyvinylalcohol (PVA) dissolved in water and cellulose acetate dissolved in acetone were additional polymer/solvent systems which were investigated. Furthermore, the electrospinning process was studied: different experimental lay-outs were tested, electrostatic fields were simulated, and voltage - current characteristics of the electrospinning process were recorded. 相似文献
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Yi-nan Wu Fengting Li Yiguang Wu Weijie Jia Phillip Hannam Junlian Qiao Guangtao Li 《Colloid and polymer science》2011,289(11):1253-1260
Self-standing thiol-functionalized fibrous membrane with bimodal pore structure was successfully fabricated through the combination
of electrospinning and surfactant-directing pore formation technique. We also found that the interference of electric field
as well as the rapid solvent evaporation during the electrospinning process has a negative effect on the formation of ordered
mesoporous structures. As high-performance adsorption-based filtration system, such hierarchically structured membrane is
found to efficiently remove Cu (II) ions under high flux. 相似文献