静电纺丝法制备MWNTs/聚胺醚复合纳米纤维

用静电纺丝法制备MWNTs/聚胺醚复合纳米纤维,将收集到的无纺布通过SEM观察其微观形貌,并用Image-Pro Plus 6.0软件测量纤维的直径;分别用TG和XRD测试了复合纤维的热性能和结晶行为。结果表明,MWNTs含量较多的纺丝溶液受到的电场力较大,比较容易得到纤维,且得到的纤维直径较细;MWNTs含量为1%时溶液的可纺浓度为30%～34%;TGA分析表明,随碳管含量增加复合纳米纤维的热稳定性提高;XRD分析表明,碳管较好地分散于聚胺醚中。     

静电纺丝法制备金纳米粒子/PVP复合纳米纤维

采用水合肼还原一定浓度氯金酸溶液的方法,在聚乙烯吡咯烷酮(PVP)作保护剂的乙醇/水溶液中,成功制备出粒度较小,且高度分散的金溶胶,紫外吸收光谱证实了溶液中金纳米粒子的存在.采用静电纺丝技术制备了AuNs/PVP复合纳米纤维.采用扫描电镜(SEM)和X射线衍射(XRD)等分析手段对纤维的表面形貌等进行了表征.由扫描电镜...     

Multi-walled carbon nanotubes fabricated by electrospinning of acrylonitrile/nylon solution and subsequent carbonization

The poly(acrylonitrile) (PAN) nanofiber web interpenetrated nylon-6 nanofiber supporters were prepared by electrospinning of an acrylonitrile (AN)/nylon-6 solution. It was realized that the average diameters of PAN and nylon-6 nanofiber were 20 and 100 nm, respectively, and that the PAN nanofibers constructed spider-mat networks which were supported by the robust nylon-6 nanofiber pillars. After stabilization and carbonization above 600 degrees C, both hollow-shaped and bamboo-shaped multi-walled carbon nanotubes (MWCNTs) were formed with the diameter range from 5 to 20 nm. The morphology and structure of MWCNTs had been further investigated by the combination techniques of transmission electron microscopy (TEM), electron diffraction (ED), X-ray diffraction (XRD) and elemental analyzer (EA).     

静电纺PVDF/SiO_2原位复合隔膜的研究

采用原位复合溶胶-凝胶法配制复合纺丝液,通过高压静电纺丝制备出PVDF/SiO2复合纳米纤维膜。通过SEM表征了PVDF/SiO2复合纳米纤维的纺丝效果,同时对比了使用两种方法添加6%SiO2制得的PVDF静电纺复合纳米纤维的表面形貌及力学性能。研究了原位纳米SiO2的加入对膜的孔径变化以及力学性能的影响。结果表明,原位硅的加入,增加了纤维的表面粗糙度;降低了复合膜内的微孔直径,并使得微孔直径分布更加集中;改善了膜的力学性能,添加6%原位硅时效果最佳。在SiO2含量为6%时,与直接添加相比,原位复合法制得的复合膜力学性能更佳。     

Characterization and mechanical performance comparison of multiwalled carbon nanotube/polyurethane composites fabricated by electrospinning and solution casting

Multiwalled carbon nanotube/polyurethane (MWNT/PU) composites were prepared by electrospinning and solution casting. The morphological and thermal properties, and mechanical performance of the nanofiber and film composites were characterized and compared. The tensile strength of neat PU film was 9-fold higher than that of neat PU nanofibrous mat. The incorporation of MWNTs increased the tensile strength and modulus of the composite nanofibers by 69% and 140%, respectively, and 62% and 78%, respectively for composite films. The MWNT/PU composites showed an improved thermal degradation behavior, with the incorporation of low MWNT content in the composites.     

Top-down process based on electrospinning, twisting, and heating for producing one-dimensional carbon nanotube assembly

Multiwalled carbon nanotube (MWNT)/poly(vinyl butyral) (PVB) composite nanofibers were prepared by electrospinning, successive twisting and heat treatment. The MWNTs were highly oriented in an electrified thin jet during electrospinning. The heat treatment of the twisted electrospun nanofiber yarns produced the characteristics of the CNT in the composite nanofiber yarns and enhanced their electrical properties, mechanical properties, and thermal properties. The electrical conductivity of the heated yarn was significantly enhanced and showed the maximum value of 154 S cm(-1) for the yarn heated at 400 °C. It is an order of magnitude higher than other electrospun CNT composite materials. These results demonstrated that the novel top-down process based on electrospinning, twisting, and heat treatment provide a promising option for simple and large-scale manufacture of CNT assemblies.     

再生丝素/聚乙烯醇共混纳米纤维的制备及表征

以三氟乙酸、二氯甲烷和水为溶剂,采用静电纺丝的方法制备再生丝素/聚乙烯醇共混纳米纤维。分析了共混配比对相容性及静电纺丝的影响,采用扫描电镜、X射线衍射仪、红外光谱仪等对所得纤维的形态与结构进行了表征,测试了纳米纤维的力学性能,结果表明:丝素分子和聚乙烯醇分子间发生了某种程度的相互作用,相容性得到改善,添加聚乙烯醇的丝素纳米纤维的力学性能有明显改善。     

Structures,thermal stability,and crystalline properties of polyamide6/organic-modified Fe-montmorillonite composite nanofibers by electrospinning

In the present work, Fe-montmorillonite (Fe-MMT) was synthesized by hydrothermal method, and then was modified by cetyltrimethyl ammonium bromide (CTAB). The polyamide6 (PA6)/organic-modified Fe-montmorillonite (Fe-OMT) composite nanofibers were prepared by facile compounding and electrospinning. Fe-OMT was first dispersed in N, N-dimethyl formamide and then compounded with PA6 which was dissolved in formic acid. The composite solutions were electrospun to form PA6/Fe-OMT composite nanofibers. The structure, morphology, thermal stability, and crystalline properties of the composite nanofibers were characterized by Fourier transfer infrared (FTIR) spectra, Energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), High-resolution electron microscopy (HREM), Scanning electron microscopy (SEM), and Thermogravimetric analyses (TGA), respectively. It was found that the silicate clay layers were well exfoliated within the composite nanofibers and were oriented along the fiber axis. The SEM images indicated that the loading of Fe-OMT decreased the diameters of composite nanofibers. TGA analyses revealed that the thermal stability was notably improved in the presence of silicate clay. It was also observed from wide-angle XRD analyses that the presence of nanoclays improved the γ-form crystals and induced the formations of α-form crystals of the PA6, attributed to effective nucleating effects of silicate clay platelets.     

PLGA/TSF静电纺纳米纤维的仿生矿化及生物相容性

利用静电纺丝和模拟体液仿生矿化技术制备了聚乳酸-羟基乙酸共聚物/柞蚕丝素/羟基磷灰石((PLGA/TSF/HA)骨组织工程复合支架。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射测试(XRD)和热重分析(TG)对复合纳米纤维的形貌结构进行了表征。此外,在复合纳米纤维支架材料上接种人骨髓间充质干细胞(hMSCs),通过四甲基偶氮噻唑蓝比色(Four methyl azo thiazole blue colorimetric,MTT)法,观察细胞在材料表面的生长情况评价纳米纤维的生物相容性。结果显示,PLGA/TSF纳米纤维毡具有精细的三维结构,纤维直径分布均匀,表面光滑。矿化后HA颗粒均匀地分布在PLGA/TSF纳米纤维表面,矿物含量约占63%。与PLGA/TSF纳米纤维支架相比,PLGA/TSF/HA纳米纤维支架的亲水性、生物相容性都得到显著提高。     

Release of lysozyme from electrospun PVA/lysozyme-gelatin scaffolds

This article describes an electrospinning process in fabricating ultra fine fibers with core-shell structure. A biodegradable polymer, poly(vinyl alcohol) (PVA), was used as the shell; lysozyme was a kind of antioxidant; and gelatin were used as the core.Morphology and microstructure of the ultra fine fibers were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analysis. As a comparison, composite nanofiber PVA/lysozyme-gelatin blend was prepared by a normal electrospinning process. In vitro drug release behaviors of the nanofibrous membranes were determined in phosphatebuffered saline (PBS) solution. It was found that core-shell nanofibers PVA/lysozyme-gelatin obviously exhibit higher initial release rates compared to that of PVA/lysozymegelatin blend nanofibers. The current method may find wide application in controlled release of bioactive proteins and tissue engineering.     

Free-standing TiO<Subscript>2</Subscript>–SiO<Subscript>2</Subscript>/PANI composite nanofibers for ammonia sensors

Free-standing TiO₂–SiO₂/polyaniline (TS/PANI) composite nanofibers were prepared by electrospinning, in situ polymerization and calcination method. The effect of tetra-n-butyl titanate (TBT) in the electrospinning solution on the morphology and the ammonia sensing properties of TS/PANI composite nanofibers were investigated. The obtained nanofibers were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, thermo-gravimetric analysis and gas sensor test system. It is proved that too much TBT in the solution would make the fibrous morphology and ammonia sensing properties worse. Gas sensing tests showed that the TS/PANI composite nanofibers ammonia sensor can work at room temperature and possess ideal response values, selectivity and repeatability. With the increase in TiO₂ content in the TS nanofibers, the ammonia sensing properties were improved because of the increase in P–N heterojunctions formed between TiO₂ and PANI in the sensors.     

魔芋葡甘聚糖/卡拉胶/聚丙烯酰胺纳米纤维膜的结构与性能

采用静电纺丝技术制备魔芋葡甘聚糖/卡拉胶/聚丙烯酰胺纳米纤维膜。采用旋转流变仪、扫描电子显微镜、红外光谱分析和差示扫描量热计表征纳米纤维膜的表观形貌、特征官能团以及热稳定性和微观结构。结果表明,卡拉胶和聚丙烯酰胺的加入能明显影响复合溶胶的流变特性,分子之间存在明显的相互作用,纳米纤维膜表面逐渐光滑,纳米纤维的粗细趋于均匀且结点明显减少,其直径范围在80~120nm之间,纳米纤维膜的热稳定性随卡拉胶和聚丙烯酰胺含量增加而增强。     

Anatase TiO2 nanoparticles/carbon nanotubes nanofibers: preparation, characterization and photocatalytic properties

In the present work, we report the preparation and photocatalytic properties of hybrid nanofibers/mats of anatase TiO₂ nanoparticles and multi-walled carbon nanotubes (MWNTs) using combined sol–gel and electrospinning techniques. Poly(vinyl pyrrolidone) is used as a base polymer in the electrospinning suspension to assist the formation of nanofibers and subsequently removed by calcination. The hybrid nanofibers are characterized using XRD, Raman spectra, FT-IR, XPS, SEM, TEM and N₂ adsorption measurements. The results show that MWNTs are encapsulated by in-situ formed anatase TiO₂ nanoparticles, with chemical bonding C–O–Ti between anatase TiO₂ nanoparticles and MWNTs. Hybrid nanofibrous mats with moderate content of MWNTs (mass ratio TiO₂:MWNTs = 100:20) exhibit enhanced adsorption ability and excellent photocatalytic activity. The composition, diameter and morphology of hybrid nanofibers can be tuned by varying sol–gel formulation, electrospinning parameter and post-treatment condition. TiO₂/MWNTs hybrid nanofiber and mats have promising applications in water purification and solar cell areas.     

Fabrication and characterization of FePt magnetic nanofibers via electrospinning technique

L1₀-structured platinum–iron (FePt) nanofibers were successfully synthesized by electrospinning technique, followed by calcination and reduction processes. In the preparation procedure, ferrous chloride tetrahydrate [Fe(Cl)₂?4H₂O] and iron nitrate nonahydrate [Fe(NO₃)₃?9H₂O] were, respectively, used as iron sources contained in precursor solution for electrospinning. Subsequently, the FePt nanofibers were obtained from the calcination in air and the followed reduction in hydrogen (H₂) of the as-spun FePt/PVP composite nanofibers. The FePt nanofibers were characterized by X-ray diffractometer, scanning electron microscopy, transmission electron microscopy, and superconducting quantum interference device magnetometry. It was found that the different iron salt used in the spinning solutions could highly affect the FePt nanofiber morphology, crystallite size, and the magnetic properties. The FePt nanofibers, resulted from the spinning solution containing iron dichloride tetrahydrate, were of better crystallinity and well-defined fibrous morphology with an average diameter of about 110 nm. Additionally, the considerably large coercivity of 10.27 kOe was recorded from the above FePt nanofibers.     

Physiochemical characterizations of electrospun (ZnO–GeO<Subscript>2</Subscript>) nanofibers and their optical properties

In this study, nanofiber mats consisting of two potential metal oxides were produced by electrospinning technique. An aqueous solution of zinc acetate dihydrate and germanium isopropoxide was mixed with polyvinyl alcohol solution to prepare a sol–gel that was electrospun at 20 kV. The obtained nanofiber mats were dried under a vacuum at 80 °C for 24 h and then calcined in air at different temperatures and soaking times. Physiochemical characterizations have affirmed that nanofibers composed of zinc oxide-germanium dioxide (ZnO–GeO₂) can be prepared by calcination at different temperatures. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the Brunauer–Emmett–Teller (BET) technique were employed to characterize the as-spun nanofibers and the calcined product. The specific surface area of the calcined product decreased with increases in temperature. X-ray powder diffractometery (XRD) analysis was used to study the chemical composition and the crystallographic structure. The optical properties of the as-prepared ZnO–GeO₂ nanofibers were also studied.     

静电纺丝复合纳米纤维研究进展

静电纺丝是一种利用聚合物溶液或熔体在强电场中进行喷射纺丝的加工技术,是获得纳米尺寸纤维的有效方法之一。然而单一组分的纳米纤维已经难以满足应用的需求,而采用两种或两种以上的聚合物(或聚合物/填料颗粒)进行静电纺丝得到的复合纳米纤维逐渐受到了人们的关注。文中总结了由静电纺丝技术制备的复合纳米纤维及其性能等方面的研究进展。主要包括复合物/碳复合纳米纤维、聚合物/金属复合纳米纤维、聚合物/粘土复合纳米纤维、共混物复合纳米纤维、装饰型复合纳米纤维等。     

The effect of acetic acid on morphology of PZT nanofibers fabricated by electrospinning

Lead zirconate titanate (PZT)/poly vinyl acetate (PVAc) green nanofibers were spun by electrospinning PZT/PVAc mixture. The acidification (acetic acid) effect of PZT/PVAc solution on the morphology of PZT ceramic fibers calcined at various temperatures was investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The PZT ceramic fibers processed with acetic acid (CH₃COOH) turned out to be thinner and more compact, compared to the fiber without it. It was also evident that there was an optimal concentration of acetic acid for the dense PZT nanofiber. In addition, FTIR and XRD revealed that the complete perovskite formation was achieved by the calcination between 650 °C and 700 °C.     

Preparation and characterization of silica nanoparticulate-polyacrylonitrile composite and porous nanofibers

In this study, polyacrylonitrile (PAN) composite nanofibers containing different amounts of silica nanoparticulates have been obtained via electrospinning. The surface morphology, thermal properties and crystal structure of PAN/silica nanofibers are characterized using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, wide-angle x-ray diffraction (WAXD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). The results indicate that the addition of silica nanoparticulates affects the structure and properties of the nanofibers. In addition to PAN/silica composite nanofibers, porous PAN nanofibers have been prepared by selective removal of the silica component from PAN/silica composite nanofibers using hydrofluoric (HF) acid. ATR-FTIR and thermal gravimetric analysis (TGA) experiments validate the removal of silica nanoparticulates by HF acid, whereas SEM and TEM results reveal that the porous nanofibers obtained from composite fibers with higher silica contents exhibited more nonuniform surface morphology. The Brunauer-Emmett-Teller (BET) surface area of porous PAN nanofibers made from PAN/silica (5?wt%) composite precursors is higher than that of pure nonporous PAN nanofibers.     

多壁碳纳米管/聚乳酸复合超细纤维的制备及性能

通过静电纺丝法制备出多壁碳纳米管（MWNTs）增强聚乳酸（PLA）复合超细纤维膜。用扫描电镜、透射电镜、差示扫描量热仪、热重分析仪对MWNTs/PLA复合超细纤维进行了表征,并进行了拉伸测试。结果表明,MWNTs分散于PLA纤维中,随着MWNTs含量的增加,纤维平均直径先减小后增大,MWNTs的加入会降低PLA的结晶度...     

异质结型NiO/ZnO复合纳米纤维的制备及光催化性能

采用静电纺丝技术, 以聚乙烯醇(PVA)和醋酸锌[Zn(CH₃COO)₂]为前驱体, 制备纯ZnO纳米纤维, 并以其为基质, 醋酸镍为镍源, 通过溶剂热法制备了NiO/ZnO复合纳米纤维. 利用X射线衍射(XRD)、扫描电镜(SEM)、高分辨透射电镜(HRTEM)和荧光光谱(PL)等分析测试手段对样品的结构和形貌进行表征。以罗丹明Ｂ的脱色降解为模式反应, 考察了样品的光催化性能。结果表明: NiO粒子均匀地负载到ZnO纳米纤维上, 得到了异质结型NiO/ZnO复合纳米纤维光催化材料, 与纯ZnO纳米纤维相比光催化活性明显提高, 且易于分离、回收和再利用。循环使用3次, RB的脱色率仍保持在89%以上。