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1

Nanofabric nonwoven mat for filtration smoke and nanoparticles

100%

Lackowski M. , Krupa A. , Jaworek A.

Polish Journal of Chemical Technology

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2013

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tom Vol. 15, nr 2

48--52

EN

The process of production of filtration mats of various thickness from PVC and PVDF polymers by the electrospinning method is presented in the paper. Filtration of nanoparticles and submicron particles is an important problem in industry and health protection systems, in particular in air-conditioning and ventilation appliances. This problem can be effectively solved by application of non-woven fibrous filtration mats. The experimental investigations of mechanical properties of nanofibrous filtration mats produced by electrospinning and the measurements of removal efficiency of submicron particles from flowing gas have indicated potential usefulness of these nanomats for gas cleaning of air-conditioning systems and/or ventilation ducts. The experimental results obtained for cigarette smoke of a mass median diameter of about 1 μm, used as test particles, have shown that nonwoven nanofibrous filtration mats produced by electrospinning have a good filtration efficiency for nano- and submicron particles, owing to a pressure drop similar to HEPA filters. Particles of this size are particularly difficult to be removed from the flow by a conventional method, for example, by a cyclone or electrostatic precipitator.

2

Mineralization and degradation of poly(ε -caprolactone) / hydroxyapatite electrospun membranes

100%

Rajzer I. , Kwiatkowski R. , Sarna E. , Janicki J.

Engineering of Biomaterials

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2011

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tom Vol. 14, no. 106-108

5--9

EN

The aim of this work was to study mineralization and degradation behavior of poly(ε-caprolactone) membranes modified with hydroxyapatite. The membranes have been obtained by electrospinning method. In vitro mineralization and degradation processes were carried out in simulated body fluid (SBF) as the release medium. The weight loss of the samples, water uptakes, pH and calcium, potassium, sodium ions concentrations of the solutions were determined. The chemistry and microstructure of the membranes after different times of incubation in SBF were characterized using SEM, FTIR, and XRD methods. The results of in vitro study in SBF indicate that incorporation of n-HAp strongly activates precipitation of the apatite like materials on the surface of nanofibers.

3

Nanofabric nonwoven mat for filtration smoke and nanoparticles

100%

Lackowski M. , Krupa A. , Jaworek A.

Polish Journal of Chemical Technology

|

2013

|

tom 15

|

nr 2

48-52

EN

The process of production of filtration mats of various thickness from PVC and PVDF polymers by the electrospinning method is presented in the paper. Filtration of nanoparticles and submicron particles is an important problem in industry and health protection systems, in particular in air-conditioning and ventilation appliances. This problem can be effectively solved by application of non-woven fibrous filtration mats. The experimental investigations of mechanical properties of nanofibrous filtration mats produced by electrospinning and the measurements of removal efficiency of submicron particles from flowing gas have indicated potential usefulness of these nanomats for gas cleaning of air-conditioning systems and/or ventilation ducts. The experimental results obtained for cigarette smoke of a mass median diameter of about 1 μm, used as test particles, have shown that nonwoven nanofibrous filtration mats produced by electrospinning have a good filtration efficiency for nano- and submicron particles, owing to a pressure drop similar to HEPA filters. Particles of this size are particularly difficult to be removed from the flow by a conventional method, for example, by a cyclone or electrostatic precipitator.

4

Fabrication of Porous Silica Fibers by Electrospinning for Sound Absorbing Materials

100%

Cho Y.-S. , Lee H. J.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 3

1497--1502

EN

Macroporous silica fibers having spherical cavities were fabricated by electrospinning using the spinning solution prepared from the mixed dispersion of tetraethylorthosilicate (TEOS) and polystyrene nanospheres as precursor and sacrificial templates, respectively, by injection through metallic nozzle. By applying electric field, the electro-spun fibers obtained by evaporation-driven self-assembly were collected on flat substrate or rotating drum, followed by the removal of the templates by calcination. The sound absorption coefficient of the porous fibers was measured by impedance tube, and the measured value was larger than 0.9 at high frequency region of incident waves. The surface of the resulting fibers was modified using fluorine-containing silane coupling agent to produce superhydrophobic fibrous materials to prevent the infiltration of humidity.

5

Evaluation of PCL and PCL/HAp scaffolds processed by electrospinning and porogen leaching techniques

100%

Rajzer I.

Engineering of Biomaterials

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2011

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tom Vol. 14, no. 103

4--7

EN

In order to improve the pore size of the polycapro-lactone (PCL) and polycaprolactone/hydroxyapatite (PCL/HAp) nanofibrous scaffolds, salt-leaching technique together with electrospinning method were applied. Salt particles were incorporated within the polymer nanofibrous matrix and then were leached out to generate some macropores. Microstructure, pore size distribution and average fibre diameter of the scaffold were investigated by scanning electron microscopy and PMI capillary flow porometer. Mechanical properties were determined by means of tensile test. Presence of hydroxyapatite and chemical characterization of the scaffold were done by FTIR analysis.

6

Electrospinning of the hydrophilic poly (2-hydroxyethyl methacrylate) and its copolymers with 2-ethoxyethyl methacrylate

100%

Přádný M. , Martinová L. , Michálek J. , Fenclová T. á. , Krumbholcová E.

Open Chemistry

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2007

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tom 5

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nr 3

779-792

EN

The goal was to electrospin 2-hydroxyethyl methacrylate - based biocompatible polymers and prepare submicron fibres (nanofibers) for biomedicinal applications. Syntheses of poly(2-hydroxyethyl methacrylate) (HEMA) and its copolymer with 2-ethoxyethyl methacrylate (EOEMA), and their characterization by viscometry and molecular weight are described. Their relation to electrospinning is discussed. Electrospinning of HEMA homopolymer from water-ethanol is successful for molecular weights 6.31 × 105 and 1.80 × 106 g/mol. Electrospinning of HEMA/EOEMA copolymers is feasible from ethanol. [...]

7

Surface characterization of the electrospun chitosan nanofibers after methane plasma treatment

100%

Rożek Z. , Lubasova D. , Matousek J. , Louda P. , Niedzielski P. , Mitura S.

Engineering of Biomaterials

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2010

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tom Vol. 13, no. 94

2--6

EN

Present nanofiber technology is one of the most important objects in the recent research topics. Electrospinning is a unique technology that can produce non-woven fibrous materials with interesting characteristics such as diameters ranging from sub-micron to several nanometers, high surface to volume ratio, high porosity and small interfibrous pore size. Polymer nanofibres have great potential for technical applications in filtration, composites and electronics. Nanofibers are also of importance in many different applications as the drug delivery, biomaterials and tissue engineering. For these applications there is a great need for polymer nanofibers with well defined surface properties. In this field, plasma surface treatment has been applied in the textile industry for the modification of polymer nanofibers. In this study, chitosan nanofibers were prepared by modified electrospinning method called NanospiderTM and treated with plasma in the presence of methane gas. The surface characteristics of the nanofibers after plasma treatment were examined using contact angle measurements, SEM and XPS analysis.

8

Preparation of ceramic nanofibers of iron vanadate using electrospinning method

100%

Khaksarfard Y. , Ziyadi H. , Heydari A.

Materials Science Poland

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2019

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tom Vol. 37, No. 4

645--651

EN

Because of special characteristics of vanadate compound, such as its sustainability, magneticity, high selectivity in reactions and catalytic character, this study aimed to preparation and analyzing novel ceramic iron vanadate (FeVO4) nanofibers. The ceramic nanofibers of iron vanadate were made by the combination of sol-gel and electrospinning methods. First, polyvinyl alcohol (PVA), as a matrix polymer, was mixed separately with ammonium metavanadate (NH4VO3) and iron (III) nitrate (Fe(NO3)3). As a result, the spinnable polymeric gel was obtained from the controlled mixture of these two precursors of ceramic material. Electrospinning of PVA/iron (III) nitrate/ammonium vanadate solution was done using an Electroris setup that enabled preparation of polymeric template nanofiber. Finally, iron vanadate nanofiber was obtained by calcination of polymer nanofiber at controlled temperature. The products were characterized with scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM) and Brunauer-Emmett-Teller (BET) surface area analysis.

9

Effect of electrospinning conditions on PLA fibers morphology and UV degradation

100%

Kosowska K. , Procner M. , Szatkowski P.

Engineering of Biomaterials

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2017

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tom Vol. 20, no. 143 spec. iss.

60

10

Electrospinning as a fine technique to obtain various material structures of bio-medical-purpose polyurethanes and polycarbonates copolymers

100%

Sobota M. , Włodarczyk J. , Dobrzyński P. , Kasperczyk J.

Engineering of Biomaterials

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2016

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tom Vol. 19, no. 138 spec. iss.

90

11

The preliminary studies of a structure and electrospinning of new polyurethanes based on synthetic atactic poly[(R, S)-3-hydroxybutyrate]

100%

Sajkiewicz P. , Brzeska J. , Denis P. , Sikorska W. , Kowalczuk M. , Rutkowska M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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tom Vol. 62, nr 1

55--60

EN

Novel polyurethanes based on synthetic, atactic poly[(R, S)-3-hydroxybutyrate] (a-PHB) and polycaprolactone (PCL) or polyoxytetramethylene (PTMG) diols were synthesized. It was shown that the presence of a-PHB within soft segments reduces crystallinity of PUR. Because of the low melting temperature for polyurethanes with PCL in soft segments, at this stage of work, electrospinning was limited to polyurethanes containing PTMG and a-PHB. Polyurethane containing 80% of PTMG and 20% of a-PHB was electrospun at various parameters from hexafluoro-2-propanole solution, resulting in formation of fibers with the average diameter ca. 2 μm. The fiber diameter decreased with decreasing polymer concentration in a solution and was practically insensitive to the needle-collector distance in the applied range of distances.

12

Preparation of hollow bioactive glass nanofibers by a facile electrospinning method

100%

Song B. , Wu L. , Wu C. , Chang J.

Biomedical glasses

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2015

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tom 1

|

nr 1

EN

In this communication, hollow bioactive glass (BG) nanofibers were fabricated via a single-nozzle electrospinning method. The morphology of the prepared hollow BG nanofibers was observed by SEM and TEM, and the results showed that BG nanofibers had a continuous hollow interior. The hollow BG nanofibers were incubated in simulated body fluid (SBF) to investigate their apatitemineralization ability, and the result showed that after incubation for 6 h a flower-like apatite was observed on the surface of hollowBGnanofibers, and the Fourier transform infrared (FTIR) result further confirmed the formation of apatite. The results suggested that hollow BG nanofibers could be used for drug delivery and bone regeneration applications due to their unique hollow structure and bioactivity.

13

Experiments and modelling of electrospinning process

100%

Kowalewski T. , Błoński S. , Barral S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2005

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tom Vol. 53, nr 4

385-394

EN

Very thin liquid jets can be obtained using electric field, whereas an electrically-driven bending instability occurs that enormously increases the jet path and effectively leads to its thinning by very large ratios, enabling the production of nanometre size fibres. This mechanism, although it was discovered almost one century ago, is not yet fully understood. In the following study, experimental data are collected, with the dual goal of characterizing the electro-spinning of different liquids and evaluating the pertinence of a theoretical model.

14

Multistep Heat-Treatment Effects on Electrospun Nd-Fe-B-O Nanofibers

100%

Jeon E. J. , Eom N. S. A. , Lee J. , Lee B. , Cho H. M. , On J. S. , Choa Y.-H. , Kim B. S.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 3

1433--1437

EN

Neodymium-Iron-Boron (Nd-Fe-B) magnets are considered to have the highest energy density, and their applications include electric motors, generators, hard disc drives, and MRI. It is well known that a fiber structure with a high aspect ratio and the large specific surface area has the potential to overcome the limitations, such as inhomogeneous structures and the difficulty in alignment of easy axis, associated with such magnets obtained by conventional methods. I n this work, a suitable heat-treatment procedure based on single-step and multistep treatments to synthesize sound electrospun Nd-Fe-B-O nanofibers of Φ572 nm was investigated. The single-step heat-treated (directly heat-treated at 800°C for 2 h in air) samples disintegrated along with the residual organic compounds, whereas the multistep heat-treated (sequential three-step heat-treated including three steps;: dehydration (250°C for 30 min in an inert atmosphere), debinding (650°C for 30 min in air), and calcination (800°C for 1 h in air)) fibers maintained sound fibrous morphology without any organic impurities. They could maintain such fibrous morphologies during the dehydration and debinding steps because of the relatively low internal pressures of water vapor and polymer, respectively. In addition, the NdFeO3 alloying phase was dominant in the multistep heat-treated fibers due to the removal of barriers to mass transfer in the interparticles.

15

Influence of process-material conditions on the structure and biological properties of electrospun polyvinylidene fluoride fibers

100%

Zaszczyńska A. , Sajkiewicz P. Ł. , Gradys A. , Tymkiewicz R. , Urbanek O. , Kołbuk D.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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tom Vol. 68, nr 3

627--633

EN

Polyvinylidene fluoride (PVDF) is one of the most important piezoelectric polymers. Piezoelectricity in PVDF appears in polar b and ɣ phases. Piezoelectric fibers obtained by means of electrospinning may be used in tissue engineering (TE) as a smart analogue of the natural extracellular matrix (ECM). We present results showing the effect of rotational speed of the collecting drum on morphology, phase content and in vitro biological properties of PVDF nonwovens. Morphology and phase composition were analyzed using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR), respectively. It was shown that increasing rotational speed of the collector leads to an increase in fiber orientation, reduction in fiber diameter and considerable increase of polar phase content, both b and g. In vitro cell culture experiments, carried out with the use of ultrasounds in order to generate electrical potential via piezoelectricity, indicate a positive effect of polar phases on fibroblasts. Our preliminary results demonstrate that piezoelectric PVDF scaffolds are promising materials for tissue engineering applications, particularly for neural tissue regeneration, where the electric potential is crucial.

16

Potential of electrospinning technique to drug delivery system

100%

Dzierzkowska E. , Stodolak-Zych E.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

119

17

Sensor properties of ZnO:Al nanofibres obtained by electrospinning

100%

Maziarz W. , Rydosz A. , Wysocka K. , Pisarkiewicz T.

Materials Science Poland

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2014

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tom Vol. 32, No. 2

176--180

EN

An electrospinning technology have been developed to obtain zinc oxide nanofibres doped with aluminum. Properties of the obtained nanostructures can be controlled by both the composition of a precursor and subsequent annealing treatment. The gas sensors manufactured with the use of ZnO:Al nanofibres exhibit good response to NO2 at relatively low operating temperatures. For some samples it was observed that interaction with ambient NO2 gas causes the change of conductivity from n-type to p-type at higher operating temperatures. This phenomenon was not observed for the samples annealed at higher temperature.

18

Preliminary study on the electrospun PLA–based nanofibres as biomaterials for the treatment of cartilage

100%

Magiera A. , Markowski J. , Lesiuk M. , Sieroń A. L. , Pilch J. , Błażewicz S.

Engineering of Biomaterials

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2014

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tom Vol. 17, no. 128-129

110--111

EN

Electrospinning is a simple and universal way to produce fibres from a variety of materials having diameters ranging from submicrometers to nanometers. Such fibres can be formed from resorbable and non-resorbable polymers, ceramics and their different combinations containing nanoparticles. Such a method has gained a great interest in medicine due to its ability to form a fibrous space architecture, similar to the natural extracellular matrix [1,2]. On the other hand, due to a wide range of technical facilities of electrospun fibers the method allows to create directionally-dependent space architecture of nanofibres which mimic natural tissues [3]. Considering the similarities between the microstructure created by nanofibres and the extracellular matrix, nanofibrous materials made by ES technique seem to be promising scaffolds to regenerate cartilage [4] and neural tissue [5]. A material which is used for cartilage scaffolds should mimic native cartilage, which is known to have an oriented structure associated with its mechanical and physiological functions [5]. Scaffold with a biomimetic-oriented architecture is an important requirement for tissue-engineered cartilage. In this study, PLA oriented and non-oriented fibrous scaffolds were manufactured. Selected properties of the materials were analysed and dissussed in view of the manufacture of optimal structure for cartilage tissue engineering.

19

The Preparation of PVP/Tb(AA)3phen Luminescent Nanofibers by Electrospinning

100%

Liu W. , Wang C.

Polish Journal of Chemistry

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2007

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tom Vol. 81, nr 1

79-84

EN

Composite nanofiber films of poly(vinyl pyrrolidone) (PVP) containing Tb(AA)3phen were prepared by electrospinning technique. Transmission electron microscopy (TEM) and luminescence spectroscopy were used to characterize the composite nanofiber films. TEMobservation showed that Tb(AA)3phenwas dispersed homogeneously in composite nanofibers. Luminescence measurements indicated that Tb(AA)3phen showed superior emission lines and stronger intensities in the composite nanofibers than in pure Tb(AA)3phen powder. The lifetime of Tb(AA)3phen also lengthened when it was incorporated in the composite nanofibers.

20

Fabrication and characterization of 1-D alumina (Al2O3) nanofibers in an electric field

88%

Azad A.-M. , Noibi M. , Ramachandran M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2007

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tom Vol. 55, nr 2

195-201

EN

The technique of electrospinning was employed to fabricate uniform one-dimensional inorganic-organic composite nanofibers at room temperature from a solution containing equal volumes of aluminum 2, 4-pentanedionate in acetone and polyvinylpyrrolidone in ethanol. Upon firing and sintering under carefully preselected time-temperature profiles (heating rate, temperature and soak time), high-purity and crystalline alumina nanofibers retaining the original morphological features present in the as-spun composite (cermer) fibers were obtained. Tools such as laser Raman spectroscopy, scanning and transmission electron microscopy together with energy dispersive spectroscopy and selected area electron diffraction were employed to follow the systematic evolution of the ceramic phase and its morphological features in the as-spun and the fired fibers. X-ray diffraction was used to identify the crystalline fate of the final product.