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Highlights • The electrospinning was developed for fabrication of collagen mimetic scaffold. • With addition of LA, LA assisted formation of 3D cotton-like fibrous structure. • The physicochemical properties of the as-fabricated scaffold were evaluated. Abstract The ability to mimic the topography of aligned collagen fiber bundles (A-CFB) that form the structural basis for the extracellular matrix (ECM) can be an important step in the fabrication of engineered scaffolds. Because the cell adhesion to the surface topography involve cell adhesion localized structures, topographical features, which mimics the A-CFB of the matrix can be a significant factor for cell activities. In this study, we present a novel method for the fabrication of low-density electrospun fibers mimicking A-CFB constructs. The three dimensional (3D) cotton-like A-CFB mimetic scaffold (3D-CACMS) of a mixture of lactic acid (LA) and polycaprolactone (PCL) was prepared by multiple pins rotator electrospinning (MPRES), followed by selective leaching of LA. The results of SEM, FTIR, TGA, and DSC revealed the physicochemical properties of the as-fabricated scaffold. This 3D-CACMS attempt to mimic A-CFB and can potentially meet the requirements for practical use of biomedical engineering. [ABSTRACT FROM AUTHOR]

Nano and submicrometric fibers of TiO 2 and ZnO were produced for the first time by solution blow spinning (SBS). High surface area, homogenous, crack free TiO 2 and ZnO fibers were successfully spun, as confirmed by BET surface area, X ray diffraction (XRD), transmission electron (TEM) and scanning electron (SEM) microscopy studies. TiO 2 and ZnO fibers presented mean diameters ranging from 300 nm to 600 nm and from 200 nm to 550 nm, respectively. SBS proved to be an efficient method of producing metal-oxide semiconductor nano and submicrometric fibers at high output rates when compared other fiber spinning techniques. [ABSTRACT FROM AUTHOR]

Graphene-based materials are usually expected to be good thermal conductors. Here, we report on the low thermal diffusivity of free-standing graphene fibers (GFs) fabricated by wet-spinning method. The GF sample mainly consists of freestanding graphene oxide. The radiation effect is excluded by measuring GFs of different lengths. The thermal diffusivity of the suspended GF sample is determined at (2.0–2.08)×10 −6 m 2 s −1 , and the corresponding intrinsic thermal conductivity is 1.14–1.18 W/m K. The low thermal conductivity is mainly attributed to the large thermal contact resistance and very strong phonon scattering at grain boundaries. The finding will be beneficial for thermal design of GF-based thermal energy applications. [ABSTRACT FROM AUTHOR]

This work addresses the challenge to produce fibers from the water-soluble polymer poly(vinyl alcohol) (PVA), using solution blow spinning (SBS) with forced solvent evaporation at the point of fiber formation. PVA at two different molecular weights, with different degrees of acetylation, were successfully blow spun into nano- and micro-fiber membranes, across a range of concentrations in water (12–20 w/v%). Fiber spinnability, morphology and size are correlated to precursor solution viscosity and PVA type. PVA with degree of polymerization 1100 and degree of hydrolysis 98–99% was relatively facile to spin into fibers. Difficulties in spinning high molecular weight PVA were overcome by introducing hot air at the point of fiber formation to force water evaporation. The procedure developed here opens SBS to other aqueous-based polymer and composite systems for environmentally benign fiber and membrane formation. [ABSTRACT FROM AUTHOR]

Electrospinning is not only a technique to fabricate macroscopic fiber but also a method to control the microstructure. In this study, high-temperature solution electrospinning was used to prepare isotactic polypropylene (iPP) fibers. Scanning electron microscope (SEM) observation indicates that a single electrospun iPP fiber consists of many nano-fibrils. Based on SEM observation, these nano-fibrils are shish-kebab structure. Electrostatic elongational force involved in the electrospinning process is considered to be responsible for the development of shish-kebab structure. [ABSTRACT FROM AUTHOR]

Highly porous carbon fibers based on rice straw and paper mulberry have been successfully prepared via wet spinning and carbonization process. From the comparison of the morphological structure and specific surface area, the porous carbon fibers derived from rice straw shows a high specific surface area of 2260 m 2 /g. This material exhibits excellent hydrogen storage properties with a gravimetric hydrogen uptakes of 4.35 wt% at 77 K and 10 bar. [ABSTRACT FROM AUTHOR]

Submicrometric alumina fiber mat was produced, for the first time, by the electro-blown spinning (EBS) technique and was compared with alumina fiber mats prepared using the solution blowing spinning (SBS) method. This new EBS methodology was successful in producing excellent flexible and continuous alumina fiber mat, with mean diameter of approximately 2.75 μm which was lower than the SBS alumina fiber diameter, 4.12 μm, and the diameter distribution of the EBS fiber was more uniform than the SBS’s. The EBS alumina fiber mat with pore size of 1.32 μm was obtained, which was smaller than the SBS’s (4.25 μm) prepared under the same conditions except the high potential. The lower fiber diameter and pore size made the EBS alumina fiber mat more fit for thermal filtration and other applications compared with the SBS one. This novel method might find application to produce a wide range of ceramic submicrofibrous materials, such as zirconia, ceria and titania micro- or nano-fibers. [ABSTRACT FROM AUTHOR]

Abstract: Porous silica ceramics were successfully prepared from silica spinning solution and introduced silica particles by electrospinning. After sintering, the sample was mainly composed of the introduced silica particles instead of the electrospun ceramic fibers. Therefore, the role of the introduced particles in this work was quite different from that of the introduced fillers in other electrospinning works. The porosity of the samples sintered at 1000°C and 1200°C were 62.4% and 55.6%, respectively. Furthermore, the porosity of the sintered sample can be adjusted by changing the content of the introduced silica particles. This method can be extended to prepare other porous ceramics just by changing the kinds of introduced particles. [Copyright &y& Elsevier]

Abstract: A new spinning method – pregelled gel spinning method for polyacrylonitrile (PAN) precursor fiber was reported. The physical and structural properties of the pregelled gel spun PAN precursor fibers as well as dry-jet wet spun PAN precursor fibers were studied. Compared with the dry-jet wet spun fibers, the pregelled gel spun fibers had reduced core-shell difference, circular cross sections and fewer internal pores. The pregelled gel spun fibers were found to have higher crystallinity and larger crystallite size than the dry-jet wet spun fibers. The tensile stress relaxation tests suggested that the pregelled gel spun fibers had higher elasticity and better developed supermolecular structure. [Copyright &y& Elsevier]

Abstract: Gelatin/Cerium (III) fibers with high tensile strength and good antibacterial activity were prepared by wet spinning method. The fiber structure and properties were investigated. The optical microscope (OPM) results showed that the fiber had a smooth surface and the fiber diameter was in the range of 60–90 µm. The mechanical properties tests showed that the tensile strength of gelatin/cerium (III) fibers increased greatly compared with the pure gelatin fibers. Furthermore, it was found that the gelatin/Ce (III) fibers have the antibacterial activity for Escherichia coli and Staphylococcus aureus. [Copyright &y& Elsevier]