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41.
42.
Carbon nanofibers (CNFs) dispersed epoxy resin was reinforced with unidirectional glycidyl methacrylate (GMA) grafted ultra-high molecular weight polyethylene (UHMWPE) fibers. Tensile tests were performed on unfilled, and CNF filled epoxy to identify the effect of adding CNFs on the mechanical properties of epoxy. The highest improvement in strength was obtained with 1 wt% of CNF. Tensile and flexural properties improvements in three-component nanocomposites were confirmed by obtained results. The combined use of CNFs and GMA-grafted UHMWPE fibers leads to a significant synergy in the mechanical properties of nanocomposites. The mechanisms of such synergism were analyzed by fracture studies using scanning electron microscopy.  相似文献   
43.
Electrospun nanofibers could be used to mimic the nanofibrous structure of the extracellular matrix (ECM) in native tissue.In tissue engineering,the ECM could be used as tissue engineering scaffold to ...  相似文献   
44.
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Biodegradable polymers such as poly(butylene adipate-co-terephthalate) (PBAT) have attracted great interest as alternatives to traditional petroleum-based polymers. Nonetheless, it is necessary to improve some properties of PBAT, such as mechanical strength. Cellulose nanofiber (CNF) can improve PBAT mechanical strength, but its dispersion and compatibility in the PBAT matrix require further improvement. In this study, octadecylamine (ODA) was utilized to graft-modify CNF to change the fiber-to-fiber interaction and improve its compatibility with the PBAT matrix. PBAT composites with 1 wt% CNF were prepared using a masterbatch premixing method to avoid CNF aggregation during extrusion. The effects of ODA graft modification on CNF properties were studied; varying degrees of CNF modification were investigated for their effect on PBAT properties. ODA-modified CNF (OCNF)/PBAT melt-extruded composites possessing 17.2% higher tensile strength than pure PBAT polymer were obtained without affecting the thermal stability of PBAT. As a result, surface modification of CNF with ODA is an effective strategy for improving CNF-PBAT compatibility.  相似文献   
45.
纳米碳纤维混凝土制备及其压敏性能   总被引:3,自引:0,他引:3  
在自密实混凝土配合比的基础上,制备不同掺量纳米碳纤维混凝土,并采用自行设计的数据采集系统研究了各混凝土试件的压敏性能。结果表明:采用普通制作工艺和自密实混凝土技术,可使纳米碳纤维均匀分散在混凝土材料中,当掺入胶凝材料体积0.8%~1.0%的纳米碳纤维掺量时可制备出压敏性优良的智能混凝土材料。  相似文献   
46.
The development of technologically efficient anodes for water oxidation is crucial to improve hydrogen production via water splitting. Electrodes based on metallic active sites dispersed in carbon matrices have been shown to be an attractive way to attain this goal. However, challenges remain to prevent catalyst agglomeration that otherwise can result in a decrease of performance over time.In this work, we report an alternative and efficient method to produce nickel-nickel oxide nanoparticles-embedded in carbon nanofibers (Ni–NiO/C), by the solution blow spinning (SBS) process. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show the carbon nanofibrillar matrix as a robust support, with well-dispersed nickel nanoparticles on the surface. The responses of the linear scanning voltammetry, cyclic voltammetry and electrochemical impedance spectroscopy demonstrate how a small fraction of nickel on the fiber surface (≈1.2–5.3%) is enough to promote substantial improvement in performance (η = 278 and 309 mV vs RHE for 10 mA cm?2) and a significant turnover frequency (TOF) values of 1.38 (η = 278) and 1.30 s?1 (η = 309). These promising results are correlated with a large amount of Ni3+ present on the fiber surfaces, as identified by X-ray Photoelectron Spectroscopy (XPS). This work provides a low-cost and rapid preparation technique that can be extended for the manufacture of a wide variety of electrodes based on metals supported on carbon nanofibers.  相似文献   
47.
针对Si材料储能过程中体积膨胀的问题,首先采用静电纺丝技术制备聚丙烯腈(PAN)/Si /Fe复合纳米纤维(NFs)膜,然后经化学气相沉积法在复合NFs膜上生长碳纳米管(CNTs),最后经800 ℃炭化得到PAN基Si/C/CNTs复合碳纳米纤维(CNFs)膜。借助扫描电子显微镜、透射电子显微镜、X射线衍射仪、热重分析仪等表征复合CNFs膜的结构与性能,并将其用于锂离子电池负极进行电化学性能测试。结果表明:用添加质量分数为15% 的FeSO4(占PAN)催化剂的纺丝液制备的复合CNFs膜具有独特毛毛虫结构,其可有效提升电池的电化学性能,具有2 067.9 mA·h/g的初始放电比容量,循环400圈后仍具有851.2 mA·h/g 的放电比容量,每圈的容量衰减率仅为 0.15%。  相似文献   
48.
闫涛  潘志娟 《纺织学报》2021,42(7):62-68
为实现对人体运动及生理信息的监测,利用静电纺丝法制备轻薄型取向碳纳米纤维膜(CNFM),并以此开发柔性应变传感器。重点分析了碳纳米纤维膜的结构及性能,讨论了CNFM的厚度、宽度及碳纳米纤维(CNF)的取向对传感性能的影响。结果表明:聚丙烯腈/石墨烯复合纳米纤维的取向度及CNFM的透光率可分别达到61.3%和48%;当牵伸方向平行于CNF的取向时,传感器的应变范围随CNF取向度的增加先减小后增大,随CNFM厚度及宽度的增加逐渐增加;当牵伸方向垂直于CNF的取向方向时,传感器的应变范围显著提高,但其敏感系数降低。该超薄透明型柔性应变传感器可贴附于皮肤表面,检测人体关节及心率、声带振动等运动与生理信息,也可应用于智能服装及微小形变监测等领域。  相似文献   
49.
为制备高效低阻的纳米纤维过滤膜,将无机驻极体BaTiO3纳米颗粒加入聚丙烯腈(PAN)溶液中,利用静电纺丝方法制备PAN/BaTiO3复合纳米纤维过滤膜,对其表面形貌、化学结构、水接触角、力学性能和过滤性能进行分析。结果表明:PAN/BaTiO3纳米纤维的直径比纯PAN纳米纤维略有降低,且BaTiO3纳米颗粒均匀地分散在纤维内部;与纯PAN纳米纤维膜相比,PAN/BaTiO3复合纳米纤维过滤膜的水接触角更大,抗污染能力更强,拉伸强度最高增加了75.5%;当BaTiO3质量分数为0.75%时,PAN/BaTiO3复合纳米纤维过滤膜的过滤效率为98.9%,阻力压降为42.7 Pa, 品质因子为0.105 6,其中静电吸附作用占总过滤效果的36.2%,该纤维膜过滤性能最好,且具有一定的循环使用性能。  相似文献   
50.
    
In this study, poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride with different concentrations (3, 5, 7, and 9%wt.) (PLA/PEG/BCL) composite electrospun mats were produced. PLA is a non-toxic polymer with high biocompatibility and biodegradability. However, it may be fragile due to its structure. Therefore, in this study, PEG was used as a plasticizer to improve the structural properties of PLA and it was aimed at providing antibacterial properties by adding BCL salt. Its use as an antibacterial composite nanomaterial effective against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacterial cultures and as a dermal wound dressing material has been examined in two different areas. The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion. 9% BCL-doped composite nanofiber was obtained as the smoothest and most homogeneous surface. This mat was reported to have the highest ductility. The low Tm of pure BCL salt enabled the Tg temperature of PLA/PEG/BCL composite nanofibers to be observed. It was observed that as the BCL salt ratio increased, the T5 and T10 temperatures of the nanofibers decreased and then increased. BCL-doped mats exhibited liquid absorption behavior in the range of 497%–708%. PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line. So, it has been reported that it cannot be used as a dermal wound dressing. PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus. It was suggested that it could be used in antibacterial coating applications by taking into account modern nanocoating technology.  相似文献   
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