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EN
In this study, bioactive fibres were produced using polyvinyl alcohol (PVA), gelatin, polyvinyl pyrrolidone (PVP) as a polymer matrix, and different amounts of folic acid (FA) as a vitamin using the electrospinning technique. Loading of the folic acid in the polymers was determined by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR); morphologies and average diameters were analysed by Scanning Electron Microscopy (SEM), and Thermal Gravimetric Analysis (TGA) was applied to determine thermal behaviours. The FTIR spectra and TGA thermograms showed the successful incorporation of folic acid into the fibres. SEM images showed that various smooth and heterogenous electrospun fibres were produced with average diameters ranging from 125 to 980 nm. An in-vitro study was carried out using dissolved FA in an artificial sweat solution (acidic media, pH 5.44), and UV-Vis analysis of electrospun fibres was made. The in vitro release study showed that the FA loaded nanofibres had initial vitamin burst release behaviour. The maximum vitamin release percentage of the PVA/FA, gelatin/FA, and PVP/FA fibres was obtained as 86.88%, 80.2%, and 76.66%, respectively. From these results, we can state that FA-loaded fibres can be potential candidates for transdermal patches and topical applications.
PL
Wyprodukowano elektroprzędzione bioaktywne włókna, do których wytworzenia użyto polialkoholu winylowego (PVA), żelatyny, poliwinylopirolidonu (PVP) jako matrycy polimerowej oraz różnych ilości kwasu foliowego (FA) jako witaminy. Obecność kwasu foliowegow w polimerach określono metodą spektroskopii w podczerwieni z osłabionym całkowitym odbiciem i transformacją Fouriera (ATR-FTIR); morfologię i średnie średnice analizowano za pomocą skaningowej mikroskopii elektronowej (SEM), a do określenia zachowań termicznych zastosowano analizę termograwimetryczną (TGA). Widma FTIR i termogramy TGA wykazały udane włączenie kwasu foliowego do włókien. Obrazy SEM pokazały, że wytworzono gładkie i heterogeniczne włókna elektroprzędzone o średnich średnicach w zakresie od 125 do 980 nm. Przeprowadzono badanie in vitro z użyciem rozpuszczonego FA w roztworze sztucznego potu (środowisko kwaśne, pH 5,44) oraz wykonano analizę UV-Vis włókien elektroprzędzonych. Badanie uwalniania in vitro wykazało, że nanowłókna obciążone FA wykazywały początkowo gwałtowne uwalnianie witamin. Maksymalny procent uwalniania witamin z włókien PVA/FA, żelatyna/FA i PVP/FA wyniósł odpowiednio 86,88%, 80,2% i 76,66%. Na podstawie tych wyników stwierdzono, że włókna obciążone FA mogą być potencjalnymi kandydatami do stosowania plastrów przezskórnych i zastosowań miejscowych.
2
Content available remote Electrostatic fabrication of polymer nanofibers
EN
Fabrication process of nanofibers from the liquid polymer solution using electrospinning is described in the paper. In the experiments, polyvinylidene fluoride (PVDF) and dimethylformamide (DMF) were used as a polymeric material and a solvent, respectively. Additionally, the results of the measurements of diameters of obtained fibers, current-voltage characteristics of the process and calculation of resistivity of liquid polymer are presented.
PL
W pracy przedstawiono proces elektrostatycznego wytwarzania nanowłókien z roztworu ciekłego polimeru. W procesie elektroprzędzenia w roli polimeru i rozpuszczalnika użyto odpowiednio polifluorek winylidenu (PVDF) i dimetyloformamid (DMF). Dodatkowo badania obejmowały pomiary średnic otrzymanych włókien, charakterystyk prądowo-napięciowych procesu oraz wyznaczenie rezystywności ciekłego polimeru.
PL
Nanowłókna polimerowe wzbudzają obecnie ogromne zainteresowanie ze względu na ich potencjalne wykorzystanie w różnych procesach technologicznych, np. w produkcji tkanin lub wytwarzaniu membran. Włókna te wykazują wyjątkowe właściwości, takie jak: duży stosunek powierzchni do objętości oraz duża porowatość. Znanych jest kilka metod wytwarzania nanowłókien, jednak ze względu na prostotę, powtarzalność i niewielkie koszty, najpowszechniej stosowane jest przędzenie elektrostatyczne. Przedstawiono przegląd najnowszych osiągnięć w zakresie zastosowań nanowłókien polimerowych w medycynie, obejmujący zagadnienia materiałów opatrunkowych, uwalniania substancji aktywnych oraz inżynierii tkankowej.
EN
Polymer nanofibers are currently of great interest in terms of their potential use in various technological processes, e.g. in the manufacture of textiles or membranes. These fibers are characterized by extraordinary properties such as high surface to volume ratio and high porosity. There are several methods of manufacturing nanofibers, but for reasons of simplicity, repeatability and low cost, electrostatic spinning is the most common. The article presents a review of the latest developments in the application of polymer nanofibers in medicine, including such issues as bandage materials, release of active substances and tissue engineering.
EN
The graphene-like two dimensional (2D) inorganic materials have been been shown great interest for a variety of applications. In this work, polymer composite nanofibres containing molybdenum disulfide (MoS2) nanosheets were obtained by electrospinning. The MoS2 nanosheets were well dispersed inside the fibres, and the nanofibres maintained the fibre morphology well with the MoS2 nanosheets embedded. The incorporation of MoS2 nanosheets changes polymer nanofibre morphology from round to ribbon-like. Moreover, through thermogravimetric (TG) analysis and dynamic mechanical thermal analysis (DMTA) measurements, it was found that the MoS2 nanosheets as an additive material led to an increase in thermal stability and in the storage modulus. This work comprises an extensive approach to producing a novel 2D inorganic-organic composite structure, which should be applicable for membrane engineering with enhanced thermal and mechanical stability.
PL
Dwuwymiarowe nieorganiczne materiały podobne do grafenu wywołały liczne zainteresowanie w różnych zastosowaniach. W pracy otrzymano metodą elektroprzędzenia kompozytowe nanowłókna polimerowe zawierające disiarczek molibdenu (MoS2). Nanoskładniki MoS2 były dobrze rozproszone we włóknach, a ich morfologia była na zadowalającym poziomie. Włączenie nanoskładników MoS2 zmienia nanowłókna polimerowe z morfologii okrągłej na wstążkową. Co więcej, dzięki analizie termograwimetrycznej (TG) i pomiarom dynamicznej mechanicznej analizy termicznej (DMTA) stwierdzono, że dodatek MoS2 może zapewnić wzrost stabilności termicznej i zwiększyć moduł przechowywania. Praca prezentuje rozszerzone podejście do produkcji nowej dwuwymiarowo nieorganiczno-organicznej struktury kompozytowej, która może mieć zastosowanie w wytwarzaniu membran o podwyższonej stabilności termicznej i mechanicznej.
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.
EN
Polyvinylidene fluoride (PVDF) fibrous membranes with fiber diameter from nanoscale to microscale were prepared by electrospinning. The structural parameters of PVDF fibrous membrane in terms of fiber diameter, pore size and its distribution, porosity or packing density, thickness, and areal weight were tested. The relationship between solution concentration and structural parameters of fibrous membrane was analyzed. The filtration performance of PVDF fibrous membrane in terms of air permeability and filtration efficiency was evaluated. The results demonstrated that the higher solution concentration led to a larger fiber diameter and higher areal weight of fibrous membrane. However, no regular change was found in thickness, porosity, or pore size of fibrous membrane under different solution concentrations. The air permeability and filtration efficiency of fibrous membrane had positive correlations with pore size. The experimental results of filtration efficiency were compared with the predicted values from current theoretical models based on single fiber filtration efficiency. However, the predicted values did not have a good agreement with experimental results since the fiber diameter was in nanoscale and the ratio of particle size to fiber diameter was much larger than the value that the theoretical model requires.
EN
Nanofibers were electrospun from bicomponent poly(vinyl alcohol) (PVA) and modified cationic starch (CS) mixed solution PVA/CS with different mass ratios (75/25, 50/50 and 35/65) at a total concentration of 12 wt% for all polymer compositions. For comparison, pure PVA solution was used. Electrospinning technique Nanospider (Elmarco, Czech Republic) with a rotating electrode with tines was used to obtain nanofibrous web. The influence of prepared polymer solution compositions on the structure and morphology of nanofibers and webs were investigated. Analyzing the structure and morphology of the formed nanofiber webs, it was noticed that the fineness nanofibers were formed from the PVA/CS solution with a mass ratio of 50/50. This ratio of solution also lets us to obtain the nanofibrous web with less sticked nanofibers on spunbond. The increase in the CS ratio by more than 50/50 had a negative influence on the diameter of nanofibers and the structure of nanofibrous web.
8
Content available remote Electrospinning of Chitosan Biopolymer and Polyethylene Oxide Blends
EN
The objective of this study is to investigate the morphological (scanning electron microscopicy images), thermal (differential scanning calorimetry), and electrical (conductivity) properties and to carry out compositional analysis (Fourier-transform infrared) of produced nonwoven fibrous materials adapted in biomedical applications as scaffolds. The orientation of produced nanofilaments was also investigated because it is considered as one of the essential features of a perfect tissue scaffold. Viscosity and electrical conductivity of solutions, used in the manufacturing process, were also disassembled because these properties highly influence the morphological properties of produced nanofibers. The nanofibrous scaffolds were fabricated via conventional electrospinning technique from biopolymer, synthetic polymer, and their blends. The chitosan (CS) was chosen as biopolymer and polyethylene oxide (PEO) of low molecular weight as synthetic polymer. Solutions from pure CS were unspinnable: beads instead of nanofibers were formed via spinning. The fabrication of pure PEO nanomats from solutions of 10 wt%, 15 wt%, and 20 wt% concentrations (in distilled water) turned out to be successful. The blending of composed CS solutions with PEO ones in ratios of 1:1 optimized the parameters of electrospinning process and provided the opportunity to fabricate CS/PEO blends nanofibers. The concentration of acetic acid (AA) used to dissolve CS finely spuninned the nanofibers from blended solutions and influenced the rate of crystallization of manufactured fiber mats. The concentration of PEO in solutions as well as viscosity of solutions also influenced the diameter and orientation of formed nanofibers. The beadless, highly oriented, and defect-free nanofibers from CS/PEO solutions with the highest concentration of PEO were successfully electrospinned. By varying the concentrations of AA and low molecular weight PEO, it is possible to fabricate beadless and highly oriented nanofiber scaffolds, which freely can found a place in medical applications.
EN
The aim of this work was to produce a thin SnO2 film by a technique combining the sol-gel method and electrospinning from a solution based on polyvinylpyrrolidone and a tin chloride pentahydrate as a precursor. The spinning solution was subjected to an electrospinning process, and then the obtained nanofiber mats were calcined for 10 h at 500°C. Then, the scanning electron microscopy morphology analysis and chemical composition analysis by X-ray microanalysis of the manufactured thin film was performed. It was shown that an amorphous-crystalline layer formed by the SnO2 nanofiber network was obtained. Based on the UV-Vis spectrum, the width of the energy gap of the obtained layer was determined.
EN
Stable dispersion of antimony-doped tin oxide nano-powder was prepared by wet attrition process by comminuting aggregated ATO nano-powder using the titanate coupling agent as a dispersant to form the chemisorbed layer on the particle surface. The feed solution of the ATO dispersion and PVP was prepared for electro-spun fibers on the glass substrate. The surface resistance of the fibrous ATO film after electrospinning for 30 minutes was in the order of 105 Ω/□, which is sufficient for anti-static coating. The optical transmittance of ATO fibers was confirmed by measuring the visible light transmittance.
EN
In this study, we demonstrate a facile and cost-effective way to synthesize Nd-Fe-B of various shapes such as powders, rods and fibers using electrospinning, heat-treatment and washing procedures. Initially Nd-Fe-B fibers were fabricated using electrospinning. The as-spun Nd-Fe-B fibers had diameters ranging 489 to 630 nm depending on the PVP concentration in reaction solutions. The different morphologies of the Nd2Fe14B magnetic materials were related to the difference in thickness of the as-spun fibers. The relationships between the as-spun fiber thickness, the final morphology, and magnetic properties were briefly elucidated. The intrinsic coercivity of Nd2Fe14B changed with the change in morphology from powder (3908 Oe) to fiber (4622 Oe). This work demonstrates the effect of the Nd-Fe-B magnetic properties with morphology and can be extended to the experimental design of other magnetic materials.
EN
Nowadays, the main limitation for clinical application of scaffolds is considered to be an insufficient vascularization of the implanted platforms and healing tissues. In our studies, we proposed a novel PLA-based hybrid platform with aligned and random fibrous internal structure and incorporated calcium phosphate (CaP) ormoglass nanoparticles (0, 10, 20 and 30 wt%) as an off-the-shelf method for obtaining scaffolds with pro-angiogenic properties. Complex morphological and physicochemical evaluation of PLA–CaP ormoglass composites was performed before and after in vitro degradation test in SBF solution to assess their biological potential. The degradation process of PLA–CaP ormoglass composites was accompanied by numerous CaP-based precipitations with extended topography and cauliflower-like shape which may enhance bonding of the material with the bone tissue and accelerate the regenerative process. Random fiber orientation was preferable for CaP compounds deposition upon in vitro degradation. CaP compounds precipitated firstly for randomly oriented composite nonwovens with 20 and 30 wt% addition of ormoglass. Moreover, the preliminary bioactivity test has shown that BSA adsorbed to PLA–CaP ormoglass composites (both aligned and randomly oriented) with 20 and 30 wt% of ormoglass nanoparticles which was not observed for pure PLA scaffolds.
13
Content available remote Fabrication of polymeric micro-tube components - recent developments
EN
For numerous technical sectors, the achievements in past decades in manufacturing of micro-components enabled to develop new generations of products with reduced mass and volume as well as with an increasing number of functions integrated in an ever-smaller space. This continuing trend of miniaturization includes an increasing demand for polymeric tubular micro-parts applied for example in medical devices, micro-fluidic and thermal management systems. Recent research in the fabrication of polymeric micro-tube products is therefore dealing with manufacturing techniques for high-volume production, developing new processes such as micro-blow moulding or hot embossing. Similarly, measures for an increased functionalization of polymeric micro-tubes were part of investigations for medical purposes and artificial neural networks were applied to model extrusion processes. The objective of this article is to provide a structured overview about the recent advances in fabricating polymeric micro-tube components with a particular focus on the achievements in innovative shaping techniques.
DE
Die Entwicklungen im Bereich der Fertigung von Mikrobauteilen in den vergangen zwei Jahrzehnte eröffnen heute zahlreichen Industriebereichen neue Möglichkeiten für innovative Produkte mit einer zunehmend höheren Funktionsdichte bei immer kleiner werdendem Bauraum und Gewicht. Dieser anhaltende Trend zur Miniaturisierung ist auch im zunehmenden Bedarf rohrförmiger Mikrobauteile aus Kunststoffen erkennbar, beispielsweise für Anwendungen in der Medizintechnik, der Mikrofluidik oder für Wärmetauschersysteme. Aktuelle Forschungsarbeiten befassen sich daher mit Fertigungsmethoden zur Herstellung rohrförmiger Mikrokomponenten in großen Stückzahlen, wie zum Beispiel dem Mikroblasformen oder dem Heißprägen. Für Anwendungen in der Medizintechnik wurden darüber hinaus verschiedene Maßnahmen zur Schaffung erhöhter Funktionalitäten kunststoffbasierter rohrförmiger Mikrobauteile untersucht. Künstliche neuronale Netze wurden für die Abbildung von Extrusionsprozessen eingesetzt. Ziel des vorliegenden Beitrages ist es, eine strukturierte Übersicht über aktuelle Entwicklungen in der Herstellung rohrförmiger Mikrobauteile aus Kunststoffen zu geben mit einem besonderen Schwerpunkt auf innovative Techniken zur Formgebung.
EN
Novel poly(vinyl alcohol) (PVA) andchitosan (CS) or 2-hydroxyethyl methacrylate (HEMA) and nanohydroxyapatite(nanoHAp) electrospinning-produced membranes were evaluated, in terms of theirbioactivity under exposure to simulated body fluid (SBF). After soaking them inSBF for 5, 8 and 15 days, the scanning electron microscopy (SEM) images showthe accumulation of calcium carbonate or calcium phosphate SBF on the surfaceof the nanohydroxyapatite (nanoHAp). This indicates that there might be anincreased bioactivity on the surface of the nanoHAp prepared by this method.
PL
Zbadano bioaktywność nowych membran, otrzymywanych w wyniku elektroprzędzenia z hydrożeli poli(alkoholu winylowego) (PVA) z chitozanem (CS), metakrylanem 2-hydroksyetylu (HEMA) i/lub nanohydroksyapatytem (nanoHAp), poddanych działaniu symulowanego płynu ustrojowego (SBF). Metodą skaningowej mikroskopii elektronowej (SEM) stwierdzono, że po zanurzeniu wytworzonych membran w roztworze SBF na 5, 8 i 15dni na powierzchni cząstek nanoHAp w badanych próbkach nastąpiła akumulacja cząsteczek węglanów i fosforanów wapnia pochodzących z SBF, co dowodzi, że tą metodą można zwiększyć bioaktywność przygotowanych membran, przeznaczonych do zastosowania w rekonstrukcji tkanki kostnej.
15
Content available remote Preparation of ceramic nanofibers of iron vanadate using electrospinning method
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.
EN
Electrospinning can be used to create nanofiber mats from diverse polymers which can be used as filters etc. Depending on the spinning parameters, also nano-membranes, i.e. non-fibrous mats, can be produced as well as mixtures from both morphologies. The ratio of membrane to fibrous areas can be tailored by the distance between the high voltage electrode and substrate. Here the impact of the mat morphology on the water vapour permeability through polyacrylonitrile nanofiber mats with different membrane-like areas is shown, allowing for tailoring the permeability between 0.1 Pa m²/W and more than 10 Pa m²/W. In this way it is possible to create the finest filters as well as nearly impenetrable thin membranes with the same technology.
PL
Elektroprzędzenie można stosować do tworzenia mat z nanowłókien z różnorodnych polimerów, które mogą być stosowane jako filtry itp. W zależności od parametrów przędzenia, można wytwarzać także nanobłonki, tj. maty niewłókniste, jak również ich hybrydy. Stosunek powierzchni membrany do części włóknistej może być regulowany przez odległość między elektrodą wysokiego napięcia a podłożem. W pracy pokazano wpływ morfologii maty na przepuszczalność pary wodnej poprzez poliakrylonitrylowe maty z nanowłókien z obszarami membranopodobnymi, pozwalając dostosować przepuszczalność między 0,1 Pa·m²/W i ponad 10 Pa·m²/W. Dzięki temu sposobowi możliwe jest tworzenie najlepszych filtrów, a także prawie nieprzeniknionych cienkich membran z zastosowaniem tej samej technologii.
EN
In this study, after the synthesis of zinc cyclohexane mono carboxylate, its chemical structure was analysed with FTIR and TGA. Then electrospun polyvinylpyrrolidone nanofibres containing zinc cyclohexane mono carboxylate were produced and antibacterial properties of the nanowebs obtained were investigated for their use in the textile field. When the FTIR results of the nanofibres containing different concentrations of zinc cyclohexane monocarbocylate are examined, an –OH peak similar to that of PVP fibres is noticed. These results clearly indicate that zinc cyclohexane monocarboxylate is included in PVP. When the TGA spectra of CHMCZn doped nanofibres at different ratios are examined, it is seen that they give more similar results than polyvinylprolidone nanofibres alone. According to the SEM-EDX analyses, it was observed that the fibre diameters obtained were in the range of 145-947 nm. On the other hand, antimicrobial activity against B. subtilis, S. aureus and E. coli strains was detected, regardless of the CHMCZn concentration.
PL
W pracy analizowano za pomocą FTIR i TGA strukturę chemiczną syntetyzowanego monokarboksylanu cykloheksanu cynku. Następnie metodą elekroprzędzenia wytworzono nanowłókna poliwinylopirolidonowe zawierające monokarboksylan cynkowo-cykloheksanowy i zbadano właściwości antybakteryjne otrzymanych włókien pod kątem ich zastosowania w branży tekstylnej. Podczas badania wyników FTIR nanowłókien zawierających różne stężenia monokarbocylanu cynkowo-cykloheksanowego zauważono pik -OH podobny do występującego w przypadku włókien PVP. Te wyniki wyraźnie wskazują, że monokarboksylan cykloheksanu cynku jest zawarty w PVP. Wykonano badania widm TGA nanowłókien domieszkowanych CHMCZn w różnych proporcjach. Po wykonaniu analiz SEM-EDX zaobserwowano, że otrzymane średnice włókien mieściły się w zakresie 145–947 nm. Ponadto wykryto aktywność przeciwdrobnoustrojową przeciwko szczepom B. subtilis, S. aureus i E. coli, niezależnie od stężenia CHMCZn.
EN
Electrospinning is a technique used to manufacture nano- and submicron fibers based on synthetic or natural polymers. Additionally, biomaterials used in the electrospinning procedure can be modified by bioactive compounds, e.g. peptides or growth factors. The microstructure of the obtained fibrous scaffolds mimics natural extracellular matrix (ECM) environment. The size and the microstructure of the fibrous scaffolds are considered to be suitable for cells adhesion and proliferation. Various design features of the electrospinning device (e.g. the shape of the collector, the shape of the nozzle, the direction of the applied voltage) or electrospinning conditions (e.g. humidity, temperature) allows to control properties of the fibers (their shape, diameter, porosity). Novel structures, such as core-shell fibers, porous fibers attracted wide attention due to their properties and functionalities. Porous fibers or fibers with nanoscaled structures can be obtained in several ways. These methods are mainly focused on using high humidity and highly volatile solvent applied in the electrospinning process. The core-shell structure can be obtained by coaxial electrospinning. That binary fiber has ability to control the release rate of drug enclosed within the shell or core. The drug release profile can be also modified by loading the pharmacological agent either directly to the spinning solution or its post immobilization.This diversity of the electrospun fibers is a reason for non-woven materials to be considered for application as drug carriers. The review of electrospinning methods presented here proves that the control over fibers surface area, morphology and the choice of polymer enable modelling of drug release kinetics.
EN
Constantly developing nanotechnology provides the possibility of manufacturing nanostructured composites with a polymer matrix doped with ceramic nanoparticles, including ZnO. A specific feature of polymers, i.e. ceramic composite materials, is an amelioration in physical properties for polymer matrix and reinforcement. The aim of the paper was to produce thin fibrous composite mats, reinforced with ZnO nanoparticles and a polyvinylpyrrolidone (PVP) matrix obtained by means of the electrospinning process and then examining the influence of the strength of the reinforcement on the morphology and optical properties of the composite nanofibers. The morphology and structure of the fibrous mats was examined by a scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS) and Fourier-transform infrared spectroscopy (FTIR). UV –Vis spectroscopy allowed to examine the impact of zinc oxide on the optical properties of PVP/ZnO nanofibers and to investigate the width of the energy gap.
EN
Purpose: The article focuses on the production of polymer nanofibres from poly(lactic acid) using the electro-spinning method, i.e. the technique of forming fibres in an electrostatic field. The main aim of the publication was to analyse the influence of the distance between electrodes on the morphology of one-dimensional polymeric materials obtained. Design/methodology/approach: In the practical part of the study solutions of polylactide in acetone and a mixture of chloroform/dimethylformamide (DMF) were produced. After 72 hours of mixing, no homogeneous solutions were obtained, therefore a solution consisting of a polylactide dissolved in chloroform was prepared, to which dimethylformamide was added in order to dilute the mixture. The morphology of the nanostructures obtained was analysed by means of a scanning electron microscope (SEM) equipped with an X-ray energy dispersion spectrometer (EDS), which allowed to analyse the chemical composition of the nanofibres produced. The electro-spinning method used to obtain fibres is characterized by high versatility - it gives the possibility to produce fibres from a wide range of polymers. Electro-spinning is also an economic method, and spinned fibres have a wide application potential. Findings: Nanofibres obtained by electro-spinning from the previously produced solution, regardless of the distance between the nozzle and the collector (10 or 20 cm) did not show any significant discrepancies in the values of measured diameters. Fibres obtained at increased distance between electrodes (20 cm) are characterized by a smaller average diameter value, but the difference is small, fluctuating between 48-49 nm. In the case of the sample formed during electro-spinning at the distance of the nozzle - collector equal to 10 cm and the sample produced at the distance doubled, no defects in the structure of the obtained nanofibres were observed. The analysis of topographic images of surfaces produced in the course of nanostructures' work did not show any significant influence of the distance between the nozzle and collector on the diameter of fibres. No defects in the structure of one-dimensional polymer materials obtained allowed to state that the distance between the nozzle and the collector in the range of 10-20 cm is the optimal parameter of the electro-spinning process allowing to obtain smooth, untangled fibres. Practical implications: The fibrous polymer mats obtained during the electro-spinning process of polylactide can be used as protective clothing materials, as drug delivery systems, as tissue scaffolding and as filtration membranes. Originality/value: At present, there are few articles in the literature on the electrospinning process, due to the fact that it is a constantly developing matte for the production of nanofibres. Moreover, most of the research focuses on fibres obtained from nonbiodegradable polymers, which do not have the advantages of fibres obtained from polylactide.
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