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1

Electrospun niobium oxide 1D nanostructures and their applications in textile industry wastewater treatment

Zaborowska Marta, Smok Weronika, Tański Tomasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 2

art. no. e144941

EN

Textile industry emits daily huge amounts of sewage rich in non-biodegradable organic compounds, especially in textile dyes. Such contaminants are highly soluble in water, which makes their removal difficult. Other studies suggest their carcinogenicity, toxicity and mutagenicity. A promising chemical treatment of textile wastewater is the photodegradation of dye molecules in the process of photocatalysis in the presence of a photocatalyst. One-dimensional nanostructures exhibit a high surface-to-volume ratio and a quantum confinement effect, making them ideal candidates for nanophotocatalyst material. Nb2O5 is, among other metal oxides with a wide band gap, gaining popularity in optical applications, and electrospun niobium oxide nanostructures, despite their ease and low cost, can increase the chemical removal of textile dyes from wastewater. Facile synthesis of electrospun one-dimensional niobium oxide nanofibers is presented. The nanophotocatalysts morphology, structure, chemical bonds and optical properties were examined. Based on photodegradation of aqueous solutions (ph=6) of methylene blue and rhodamine B, the photocatalytic activity was established. The photocatalytic efficiency after 180 minutes of ultraviolet irradiation in the presence of Nb2O5 nanofibers was as follows: 84.9% and 31.8% for methylene blue and rhodamine B decolorization, respectively.

2

Fabrication and Characterization of Fibrous Polycaprolactone Blended with Natural Green Tea Extracts Using Dual Solvent Systems

Mohd Rashid Ainatul Aqilah Binti, Jaganathan Saravana Kumar, Mohd Khudzari Ahmad Zahran, Ismail Ahmad Fauzi

Autex Research Journal

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2022

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Vol. 22, no. 4

404--410

EN

Nanofibrous dressings serve as an impeccable candidate in the management of wounds. Nanofibrous composites composed of polycaprolactone (PCL) and green tea using dual solvent systems at different ratios were fabricated through electrospinning. Pure PCL electrospun fibers along with composites were characterized by using scanning electron microscopy (SEM), wettability, water uptake analysis, and Fourier transform infrared spectroscopy (FTIR). SEM indicated that fibrous morphology and the diameter of PCL/green tea were smaller for chloroform/ dimethylformamide (DMF) (601 nm) and acetone/DMF (896 nm) than the pure PCL (673 nm and 1,104 nm for chloroform/DMF and acetone/DMF, respectively). Wettability of the fabricated composites was increased, and pure PCL fibers were slightly more hydrophobic (100°) than PCL/green tea (94°). Water uptake of the composites was enhanced compared with PCL significantly in acetone/DMF. The PCL/green tea nanofibrous wound dressing with enhanced physicochemical properties serves as an indispensable candidate for wound healing applications.

3

Influence of molecular weight on dielectric properties and piezoelectric constant of poly(vinylidene fluoride) membranes obtained by electrospinning

Zahari Aminatul Sobirah, Mazwir Muhammad Hafiz, Misnon Izan Izwan

Polimery

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2021

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T. 66, nr 10

532--537

EN

A significant influence of the molecular weight on the dielectric properties and piezoelectric constant of poly(vinylidene fluoride) (PVDF) membranes obtained by electrospinning was demonstrated. Electrochemical impedance spectroscopy and d33 meter were used to evaluate dielectric properties and piezoelectric constant respectively. The presence of the β-phase was determined by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The membranes with the lowest molecular weight (180,000 g/mol) possessed the best dielectric properties. They also had the highest piezoelectric constant (21 pC/N) and dielectric constant (2.9 at 50 Hz) as well as the highest β-phase content (80.25%).

PL

Wykazano istotny wpływ masy cząsteczkowej na właściwości dielektryczne i stałą piezoelektryczną membran poli(fluorku winylidenu) (PVDF) otrzymanych metodą elektroprzędzenia. Do oceny stałej piezoelektrycznej i właściwości dielektrycznych stosowano, odpowiednio, miernik d33 i spektroskopię impedancyjną. Obecność fazy β określono za pomocą spektroskopii w podczerwieni z transformacją Fouriera (FTIR) i dyfrakcji rentgenowskiej (XRD). Membrany o najmniejszej masie cząsteczkowej (180 000 g/mol) charakteryzowały się najlepszymi właściwościami dielektrycznymi. Miały również największą stałą piezoelektryczną (21 pC/N) i stałą dielektryczną (2,9 przy 50 Hz) oraz największą zawartość fazy β (80,25%).

4

Preparation and Characterisation of Vitamin-Loaded Electrospun Nanofibres as Promising Transdermal Patches

Parın Fatma Nur, Yıldırım Kenan

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 1 (145)

17--25

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.

5

Improving the Water-Repellent and Antifungal Properties of Electrospun Cellulose Acetate Materials by Decoration with ZnO Nanoparticles

Nachev Nasko, Spasova Mariya, Manolova Nevena, Rashkov Iliya, Naydenov Mladen

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 3 (147)

40--45

EN

Suitable conditions for the preparation of nano- and microstructured materials from cellulose acetate and cellulose acetate/ZnO from solutions/suspensions in aceton/water by electrospinning/electrospraying were found. The materials obtained were characterised by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and contact angle measurements. The antifungal activity of the materials obtained against Phaeomoniella chlamydospora, which is one of the main species causing diseases in grapevines, was studied as well. It was found that electrospinning of CA solutions with a concentration of 10 wt% reproducibly resulted in the preparation of defect-free fibres with a mean fibre diameter of ~780 nm. The incorporation of ZnO nanoparticles resulted in the fabrication of hybrid materials with superhydrophobic properties (contact angle 152°). The materials decorated with ZnO possessed antifungal activity against P. chlamydospora. Thus, the fibrous materials of cellulose acetate decorated with ZnO particles obtained can be suitable candidates to find potential application in agriculture for plant protection.

PL

W pracy wskazano odpowiednie warunki do otrzymywania materiałów nano- i mikrostrukturalnych z octanu celulozy i octanu celulozy/ZnO z roztworów/zawiesin w acetonie/wodzie metodą elektroprzędzenia/elektrorozpylania. Uzyskane materiały scharakteryzowano za pomocą skaningowej mikroskopii elektronowej (SEM), dokonano analizy dyfrakcji rentgenowskiej (XRD) oraz pomiarów kąta zwilżania. Zbadano również działanie przeciwgrzybiczne uzyskanych materiałów przeciwko Phaeomoniella chlamydospora, który jest jednym z głównych gatunków wywołujących choroby winorośli. Stwierdzono, że podczas elektroprzędzenia z roztworów CA o stężeniu 10% wag. w sposób powtarzalny otrzymywano włókna wolne od defektów o średniej średnicy ~ 780 nm. Wprowadzenie nanocząstek ZnO zaowocowało wytworzeniem materiałów hybrydowych o właściwościach superhydrofobowych (kąt zwilżania 152°). Materiały z dodatkiem ZnO wykazywały działanie przeciwgrzybiczne przeciwko P. chlamydospora. Stwierdzono, że otrzymane materiały mogą być stosowane w rolnictwie do ochrony roślin.

6

Comparative Analysis of Electrospinning Methods for Producing Fibres and Materials with a Predicted Structure and Complex of Properties

Filatov Ivan, Bokova Elena, Smulskaya Maria, Kapustin Ivan, Pawlowa Maria, Kovalenko Grigory

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 4 (148)

69--74

EN

Various industrial methods of electrospinning are considered. Experimental data of the results of electrospinning from solutions of chlorinated polyvinyl chloride, polyamide-6/66 and fluoroplastic F-42, obtained by various methods are presented.

PL

Rozważaniom poddano różne przemysłowe metody elektroprzędzenia. Przedstawiono dane doświadczalne wyników elektroprzędzenia z roztworów chlorowanego polichlorku winylu, poliamidu-6/66 i fluoroplastu F-42.

7

Characterization of morphology and optical properties of SnO₂ nanowires prepared by electrospinning

Tański Tomasz, Smok Weronika, Matysiak Wiktor

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 5

art. no. e137507

EN

The growing interest in one-dimensional tin oxide-based nanomaterials boosts research on both high-quality nanomaterials as well as production methods. This is due to the fact that they present unique electrical and optical properties that enable their application in various (opto)electronic devices. Thus, the aim of the paper was to produce ceramic SnO₂ nanowires using electrospinning with the calcination method, and to investigate the influence of the calcination temperature on the morphology, structure and optical properties of the obtained material. A scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR) were used to examine the morphology and chemical structure of obtained nanomaterials. The optical properties of manufactured one-dimensional nanostructures were investigated using UV-Vis spectroscopy. Moreover, based on the UV-Vis spectra, the energy band gap of the prepared nanowires was determined. The analysis of the morphology of the obtained nanowires showed that both the concentration of the precursor in the spinning solution and the calcination temperature have a significant impact on the diameter of the nanowires and, consequently, on their optical properties.

8

The Removal of Reactive Red 141 From Wastewater: A Study of Dye Adsorption Capability of Water-Stable Electrospun Polyvinyl Alcohol Nanofibers

Akduman Çigdem, Morsümbül Seniha, Akçakoca Kumbasar Emriye Perrin

Autex Research Journal

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2021

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Vol. 21, no. 1

20--31

EN

The dye production and its use in textile and related industries resulted in discharge of dye to wastewater. Adsorption for color removal is known as equilibrium separation process, and the resultant decolorization is influenced by physicochemical factors such as adsorbent surface area. The nanofiber membranes prepared by the electrospinning method have controllable nanofiber diameter and pore size distribution (PSD) with a high surface area to volume or mass ratio. In this study, polyvinyl alcohol (PVA) nanofibrous membranes were prepared by the electrospinning method at different collection times such as 3, 5 and 10 h and heat fixated at 130, 150 and 170°C for 10 min, and then, the adsorption capability of PVA nanofiber membranes for Reactive Red 141 from aqueous solution was investigated. In order to make PVA nanofibers stable to water, the nanofibrous membranes were chemically cross-linked by a polycarboxylic acid (1,2,3,4 butanetetracarboxylic acid (BTCA)). PVA nanofibrous membranes were characterized by scanning electron microscopy, thermogravimetric analysis, swelling tests and pore size analysis. The results indicated that BTCA crosslinking improved the thermal and water stability of the nanofibrous structure but has no significant effect on the pore sizes of the membranes. Adsorption of Reactive Red 141 was studied by the batch technique, and it was observed that PVA nanofibers removed approximately >80% of the dye.

9

Fabrication of Multifunctional Nano Gelatin/Zinc Oxide Composite Fibers

Zare Hamed, Nayebzadeh Shahnaz, Davodiroknabadi Abolfazl, Hataminasab Sayyed Hasan

Autex Research Journal

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2021

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Vol. 21, no. 4

403--407

EN

According to health studies, reinforcing gelatin is necessary in order to obtain the multifunctional material. In this study, nano zinc oxide (ZnO; at concentrations of 0.5%, 1% and 1.5%) was doped with gelatin and the solution was electrospun under specific conditions to obtain multifunctional gelatin/ZnO nanofibers. The morphology of the nanofibers was studied by field emission scanning electron microscope (FESEM), and energy-dispersive X-ray spectrometry (EDX) analysis indicated the presence of nano Zn on the surface of gelatin fibers. On the contrary, elemental mapping analysis proved the distribution of nano material along the nano gelatin fibers. The results show that the produced nano gelatin/ZnO composite increases the ultraviolet (UV) blocking of fabric significantly. It is also observed that electrospun gelatin/ZnO nanofibers have excellent bactericidal property against both Bacillus cereus (Gram-positive) and Escherichia coli (Gram-negative) bacteria.

10

Electrostatic fabrication of polymer nanofibers

Czapka Tomasz, Kopaniarz Tomasz, Woś Angelika

Przegląd Elektrotechniczny

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2020

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R. 96, nr 2

174--177

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.

11

Elektroprzędzone nanowłókna polimerowe do zastosowań medycznych

Winkler Angelika, Maliszewska Irena, Czapka Tomasz

Polimery

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2020

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T. 65, nr 1

18--24

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.

12

Effect of MoS2 Nanosheet Fillers on Poly(vinyl alcohol) Nanofibre Composites Obtained by the Electrospinning Method

Yuan Bin, Liu Jun, Qiu Lei, Hui Qian, Chang Meng-Jie, Li Ya-Qing

Fibres & Textiles in Eastern Europe

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2020

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Vol. 28, no. 3 (141)

62--67

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.

13

Study of the Properties and Cells Growth on Antibacterial Electrospun Polycaprolactone/Cefuroxime Scaffolds

Mijovic Budimir, Zdraveva Emilija, Bajsić Emi Govorčin, Slivac Igor, Dekaris Iva, Grgurić Tamara Holjevac, Ferri Tea Zubin

Autex Research Journal

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2020

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Vol. 20, no. 3

312--318

EN

Electrospun materials are good candidates for the design of tissue regeneration scaffolds as they can simulate the natural surroundings of tissue cells. The study proposes electrospun polycaprolactone (PCL)/cefuroxime (CFU) scaffolds for human cell culture and investigates the influence of the antibiotic content on scaffold morphology, thermal and mechanical properties. The increase in the CFU concentration resulted in the reduction of fiber diameter and number of deformations. It also influenced the reduction of scaffold thermal enthalpies and improved scaffold break strength. With regard to cell growth, the scaffolds showed precedence in greater colonization of the HeLa cells. Finally, these scaffolds showed compatibility with standard human cell lines, and thus they can be used for the repair of damaged tissues.

14

Performance of Electrospun Polyvinylidene Fluoride Nanofibrous Membrane in Air Filtration

Xiao Yuanxiang, Wen Enlong, Sakib Nazmus, Yue Zhonghua, Wang Yan, Cheng Si, Militky Jiri, Venkataraman Mohanapriya, Zhu Guocheng

Autex Research Journal

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2020

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Vol. 20, no. 4

552--559

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.

15

Influence of Modified Cationic Starch in a Mixed Poly(Vinyl Alcohol)/Cationic Starch Solution on the Electrospinning Process and Web Structure

Šateikė Jurgita, Milašius Rimvydas

Autex Research Journal

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2020

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Vol. 20, no. 1

69--72

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.

16

Electrospinning of Chitosan Biopolymer and Polyethylene Oxide Blends

Varnaitė-Žuravliova Sandra, Savest Natalja, Baltušnikaitė-Guzaitienė Julija, Abraitienė Aušra, Krumme Andres

Autex Research Journal

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2020

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Vol. 20, no. 4

426--440

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.

17

Fabrication of polymeric micro-tube components - recent developments

Hartl Christoph, Anyasodor Gerald

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

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2019

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z. 4/122

33--43

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.

18

Simulated body fluid nucleation of poly(vinyl alcohol)/nanohydroxyapatitehydrogels

Salgado-Delgado Arieli M., Hernández-Cocoletzi Heriberto, Rubio-Rosas Efrain, Escobedo-Morales Alejandro, Chigo-Anota Ernesto, Olarte-Paredes Alfredo, Salgado-Delgado Rene, Castańo Victor M.

Polimery

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2019

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T. 64, Nr 7-8

487--492

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.

19

Water Vapor Permeability through PAN Nanofiber Mat with Varying Membrane-Like Areas

Sabantina Lilia, Hes Lubos, Mirasol José Rodríguez, Cordero Tomás, Ehrmann Andrea

Fibres & Textiles in Eastern Europe

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2019

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Vol. 27, no. 1 (133)

12--15

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.

20

Production of Polyvinylpyrrolidone Nanowebs Containing Zinc Cyclohexane Mono Carboxylate via Electrospinning and Investigation of Antibacterial Efficiency

Yildiz Ayli̇n, Atav Riza, Kurc Mi̇ne Aydi

Fibres & Textiles in Eastern Europe

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2019

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Vol. 27, no. 6 (138)

91--96

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.