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Composite Nanofibers (composite + nanofiber)
Selected AbstractsCo-electrospun composite nanofibers of blends of poly[(amino acid ester)phosphazene] and gelatinPOLYMER INTERNATIONAL, Issue 5 2010Yi-Jun Lin Abstract Electrospinning is known as a simple and effective fabrication method to produce polymeric nanofibers suitable for biomedical applications. Many synthesized and natural polymers have been electrospun and reported in the literature; however, there is little information on the electrospinning of poly[(amino acid ester)phosphazene] and its blends with gelatin. Composite nanofibers were made by co-dissolving poly[(alaninoethyl ester)0.67(glycinoethyl ester)0.33phosphazene] (PAGP) and gelatin in trifluoroethanol and co-electrospinning. The co-electrospun composite nanofibers from different mixing ratios (0, 10, 30, 50, 70 and 90 wt%) of gelatin to PAGP consisted of nanoscale fibers with a mean diameter ranging from approximately 300 nm to 1 µm. An increase in gelatin in the solution resulted in an increase of average fiber diameter. Transmission electron microscopy and energy dispersive X-ray spectrometry measurements showed that gelatin core/PAGP shell nanofibers were formed when the content of gelatin in the hybrid was below 50 wt%, but homogeneous PAGP/gelatin composite nanofibers were obtained as the mixing ratios of gelatin to PAGP were increased up to 70 and 90 wt%. The study suggests that the interaction between gelatin and PAGP could help to stabilize PAGP/gelatin composite fibrous membranes in aqueous medium and improve the hydrophilicity of pure PAGP nanofibers. Copyright © 2009 Society of Chemical Industry [source] Structural characterization and dynamic water adsorption of electrospun polyamide6/montmorillonite nanofibersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Qi Li Abstract A facile compounding process, which combined nanocomposite process with electrospinning for preparing novel polyamide6/organic modified montmorillonite (PA6/O-MMT) composite nanofibers, is reported. In this compounding process, the O-MMT slurry was blended into the formic acid solution of PA6 at moderate temperatures, where the nanosized O-MMT particles were first dispersed in N,N -dimethyl formamide solvent homogeneously via ultrasonic mixing. Subsequently the solution via electrospinning formed nanofibers, which were collected onto aluminum foil. The O-MMT platelets were detected to be exfoliated at nanosize level and dispersed homogeneously along the axis of the nanofibers using an electron transmission microscope. Scanning electron microscope and atomic force microscope were used to analysis the size and surface morphology of polyamide6/O-MMT composite nanofibers. The addition of O-MMT reduced the surface tension and viscosity of the solution, leading to the decrease in the diameter of nanofiber and the formation of rough and ridge-shape trails on the nanofiber surface. The behavior of the dynamic water adsorption of composite nanofibers was also investigated and discussed in this article. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] A Rapidly Responding Sensor for Methanol Based on Electrospun In2O3,SnO2 NanofibersJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2010Wei Zheng In this paper, we presented a simple and effective electrospinning technique for the preparation of In2O3,SnO2 composite nanofibers. The morphology and chemical structure of the as-prepared samples were analyzed by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The results showed that large quantities of In2O3,SnO2 composite nanofibers with diameters from 60 to 100 nm were obtained. The In2O3,SnO2 composite nanofibers exhibited excellent gas sensing properties to methanol, such as fast response/recovery properties, high sensitivity, and good selectivity. [source] Preparation of Porous Tin Oxide Nanobelts Using the Electrospinning TechniqueJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2008An Yang The electrospinning method is adopted to prepare utralong PEO/stannic hydroxide composite nanofibers. Tin-oxide nanobelts can be obtained by calcination of the composite nanofibers in an open atmosphere. The nanobelts were characterized by a field emission scanning electron microscope, X-ray diffraction, a transmission electron microscope, a Raman spectromicroscope, and Fourier transform infrared spectroscopy. Microstructural analysis has shown that the nanobelts prepared consist of a continuous network of interconnected SnO2 grains. As a result, the SnO2 nanobelts possess a high surface area and continuous porosity, which may be applied for the fabrication of sensitive gas sensors. [source] Photocatalytic Deposition of Silver Nanoparticles onto Organic/Inorganic Composite NanofibersMACROMOLECULAR MATERIALS & ENGINEERING, Issue 10 2006Sang Kyoo Lim Abstract Summary: In this work, silver nanoparticles were embedded in electrospun organic/inorganic composite nanofibers consisting of PAN and TiO2 through photocatalytic reduction of the silver ions in silver nitrate solutions under UV irradiation. The morphology and diameter of PAN/TiO2 composite nanofibers could be controlled by varying the initial contents of TiO2 in the spinning solution. From TEM images and UV-Vis spectra, it has been confirmed that monodisperse silver nanoparticles with a diameter of ,2 nm were deposited selectively upon the titania of the as prepared composite nanofibers. The amount of Ag nanoparticles embedded on composite nanofibers was greatly influenced by the amount of TiO2 in composite nanofibers, reflecting the role of titania as the inorganic stabilizer and photocatalyst. Morphology of silver nanoparticles embedded on PAN/TiO2 composite nanofibers. [source] High Rate Silicification of Peptide-Polymer Assemblies Toward Composite NanotapesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 5 2008Stefanie Kessel Abstract Well-defined silica composite nanofibers are generated in a silicification process of self-assembled poly(ethylene oxide)-peptide nanotapes. Inspired by biological silica morphogenesis processes the nanotapes exhibit strong binding capabilities for silicic acid. Thus, pre-hydrolyzed tetramethoxysilane could be used as silica precursor. Very low concentrations (270 µM) and short contact times (10 s) are sufficient to form effectively integrated nano-composite tapes. [source] Chemical One Step Method to Prepare Polyaniline Nanofibers with Electromagnetic FunctionMACROMOLECULAR RAPID COMMUNICATIONS, Issue 5 2007Zhiming Zhang Abstract A "Chemical one step method" (COSM) is proposed to prepare electromagnetic functional composite nanofibers of polyaniline (PANI/, -Fe2O3) having a diameter of ,20 nm. In this approach FeCl3 is acts as the oxidant either for polymerization of aniline or for preparation of , -Fe2O3 magnets. Besides, it also provides protons produced by the hydrolysis process for doping PANI. It is found that the composite nanofibers have a high conductivity (10,1,,,100 S,·,cm,1) and super-paramagnetic properties (Ms,=,0.46,,,6.03 emu,·,g,1 and Hc,=,0) at room temperature, where the conductivity is mainly affected by the molar ratio of FeCl3 to aniline monomer whereas the magnetic properties are dominated by the amount of FeCl2. [source] Coaxial electrospinning of PC(shell)/PU(core) composite nanofibers for textile applicationPOLYMER COMPOSITES, Issue 5 2008Xiao-Jian Han To develop a novel functional composite material for textile application, a coaxial electrospinning technique was investigated to electrospin two different polymer solutions into core-shell structured nanofibers in which polyurethane and polycarbonate were used as core and shell materials, respectively. The resultant nanofibers were subsequently characterized by means of scanning electron microscope, transmission electron microscopy, fourier transform infrared spectroscopy, and tensile mechanical test. Furthermore, water vapour transmission rate and pliability of the resulting nonwoven mats were also measured. The preliminary results indicated that it is feasible to attach composite nanofibers, with possible fictionalization on the shell material, onto a substrate fabric. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers [source] Co-electrospun composite nanofibers of blends of poly[(amino acid ester)phosphazene] and gelatinPOLYMER INTERNATIONAL, Issue 5 2010Yi-Jun Lin Abstract Electrospinning is known as a simple and effective fabrication method to produce polymeric nanofibers suitable for biomedical applications. Many synthesized and natural polymers have been electrospun and reported in the literature; however, there is little information on the electrospinning of poly[(amino acid ester)phosphazene] and its blends with gelatin. Composite nanofibers were made by co-dissolving poly[(alaninoethyl ester)0.67(glycinoethyl ester)0.33phosphazene] (PAGP) and gelatin in trifluoroethanol and co-electrospinning. The co-electrospun composite nanofibers from different mixing ratios (0, 10, 30, 50, 70 and 90 wt%) of gelatin to PAGP consisted of nanoscale fibers with a mean diameter ranging from approximately 300 nm to 1 µm. An increase in gelatin in the solution resulted in an increase of average fiber diameter. Transmission electron microscopy and energy dispersive X-ray spectrometry measurements showed that gelatin core/PAGP shell nanofibers were formed when the content of gelatin in the hybrid was below 50 wt%, but homogeneous PAGP/gelatin composite nanofibers were obtained as the mixing ratios of gelatin to PAGP were increased up to 70 and 90 wt%. The study suggests that the interaction between gelatin and PAGP could help to stabilize PAGP/gelatin composite fibrous membranes in aqueous medium and improve the hydrophilicity of pure PAGP nanofibers. Copyright © 2009 Society of Chemical Industry [source] Synthesis of pH-responsive crosslinked poly[styrene- co -(maleic sodium anhydride)] and cellulose composite hydrogel nanofibers by electrospinningPOLYMER INTERNATIONAL, Issue 5 2009Shengguang Cao Abstract BACKGROUND: Stimuli-sensitive materials show enormous potential in the development of drug delivery systems. But the low response rate of most stimuli-sensitive materials limits their wider application. We propose that electrospinning, a technique for the preparation of ultrafine fibrous materials with ultrafine diameters, may be used to prepare materials with a fast response to stimuli. RESULTS: Poly[styrene- co -(maleic sodium anhydride)] and cellulose (SMA-Na/cellulose) hydrogel nanofibers were prepared through hydrolysis of precursor electrospun poly[styrene- co -(maleic anhydride)]/cellulose acetate (SMA/CA) nanofibers. In the presence of diethylene glycol, the SMA/CA composite nanofibers were crosslinked by esterification at 145 °C, and then hydrolyzed to yield crosslinked SMA-Na/cellulose hydrogel nanofibers. These nanofibers showed better mechanical strengths and were pH responsive. Their water swelling ratio showed a characteristic two-step increase at pH = 5.0 and 8.2, with the water swelling ratio reaching a maximum of 27.6 g g,1 at pH = 9.1. CONCLUSION: The crosslinked SMA-Na hydrogel nanofibers supported on cellulose showed improved dimensional stability upon immersion in aqueous solutions. They were pH responsive. This new type of hydrogel nanofiber is a potential material for biomedical applications. Copyright © 2009 Society of Chemical Industry [source] Assembly of Carbon,SnO2 Core,Sheath Composite Nanofibers for Superior Lithium StorageCHEMISTRY - A EUROPEAN JOURNAL, Issue 38 2010Liwen Ji Protective coating: Carbon,SnO2 core,sheath composite nanofibers are synthesized through the creative combination of electrospinning and electrodeposition processes (see figure). They display excellent electrochemical performance when directly used as binder-free anodes for rechargeable lithium ion batteries. [source] | ||||||||||