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1

Electrospinning-based PCL fibre coatings on metallic meshes for biomimetic surface engineering

Boruchowski Bartłomiej, Kurpanik Roksana, Gryń Karol, Szaraniec Barbara

Engineering of Biomaterials

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2026

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vol. 29, no. 174

art. no. 7

EN

Electrospinning represents a versatile technique for the fabrication of micro– and nanofibrous structures that mimic the architecture of biological tissues. In this study, electro- spinning was employed as a surface engineering method to functionalize metallic mesh substrates intended for potential biomaterial surface engineering applications. Steel meshes with varying geometries and opening sizes were coated with polycaprolactone (PCL) fibres using three solution variants: pure PCL, PCL modified with Tween 80 surfactant, and a hybrid system combining both fibre types. The influence of surfactant incorporation on fibre morphology, wettability, and surface energy was investigated. Microscopic observations confirmed the formation of continuous fibrous coatings across all mesh geometries, despite local variations in fibre density arising from substrate conductivity and electrostatic deposition effects. The addition of Tween 80 enabled a controlled transition from hydrophobic to superhydrophilic surface behaviour, while the hybrid coating exhibited heterogeneous wettability characteristics. Mechanical testing demonstrated that the fibrous coatings preserved structural continuity under large deformations exceeding 100% elongation. The deformation behaviour was governed by fibre reorientation and network adaptation rather than coating failure, indicating favourable mechanical compatibility be- tween the fibrous layer and the metallic substrate. These results demonstrate that electrospinning can be effectively applied to fabricate mechanically stable fibrous coatings with tunable surface properties on metallic mesh structures.

2

Structure-performance engineering of recycled acrylic membranes for air gap membrane distillation

Mohammed Safa, Waisi Basma

Ecological Chemistry and Engineering. S

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2026

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Vol. 33, nr 1

63--79

EN

Air Gap Membrane Distillation (AGMD) is an emerging and promising technology in separation processes, but its industrial adoption is limited by relatively low permeate flux. Conventional AGMD systems typically utilise thin film-cast polymeric membranes. However, electrospun nanofibrous membranes have become more popular since they possess a highly interconnected porous structure, which is able to increase mass transfer performance and availability. In this study, recycled acrylic (RA) waste powder was used to prepare a precursor solution to fabricate two types of membranes: thin film-cast membranes and electrospun nonwoven nanofibrous membranes to be evaluated in the AGMD process for water desalination application. The fabricated RA-based membranes underwent characterisation by scanning electronic microscopy (SEM), mechanical properties, water contact angle (WCA), and Fourier transform infrared spectroscopy (FTIR). Based on the results obtained, the nanofiber membrane exhibited a higher contact angle, porosity, and elasticity than the thin film cast membrane. RA-based membranes were tested in the AGMD system at different feed temperatures (45 °C, 55 °C, and 65 °C). The electrospun nanofibrous membrane performed better than the thin-film cast membrane in both permeate flux and salt rejection. The temperature of the feed increased correspondingly with the flux of permeate as well as the salt rejection. The cast membrane of thin film attained a flux of permeate of 1.48 kg/(m2‧h) with 99.98 % salt rejection. Conversely, the electrospun nanofibrous membrane had better performance with a significantly higher permeate flux rate of 7.69 kg/(m2‧h) and an almost ideal salt rejection of 99.99 %.

3

Elektroprzędzone nanowłókna polimerowe – otrzymywanie i możliwości zastosowania

Zdubek Anna, Maliszewska Irena, Kołodziej Natalia, Czapka Tomasz

Chemik

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2025

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Nr 1

53--62

PL

Wodne roztwory alkoholu poliwinylowego (PAV) (6–12%) o masach cząsteczkowych 40, 130 i 205 kDa poddano przędzeniu w celu określenia wpływu takich parametrów procesu jak masa cząsteczkowa polimeru, stężenie roztworu polimeru, napięcie elektroprzędzenia i szybkość przepływu polimeru na grubość i jakość otrzymanego nanowłókna oraz na efektywność (ciągłość) procesu przędzenia. Badaniom poddano także 10-proc. roztwory PAV zawierające 0,1, 0,2 lub 03% AgNO3 w celu otrzymania włókniny o potencjalnym działaniu bakteriobójczym wobec trzech różnych szczepów bakteryjnych: Bacillus subtilis, Staphylococcus aureus oraz Acinetobacter baumannie. Najbardziej efektywne hamowanie rozwoju bakterii przez otrzymane materiały zaobserwowano w przypadku S. aureus i A. baumannii, które są znanymi patogenami z grupy „ESCAPE”, czyli takimi, które nie poddają się klasycznej antybiotykoterapii.

EN

Aq. solns. of polyvinyl alc. (PAV) (6–12%) with mol. weights of 40, 130 and 205 kDa were electrospun to det. the effect of such process parameters as polymer mol. weight, polymer soln. concn., electrospinning voltage and polymer flow rate on the thickness and qual. of the obtained nanofibre and on the efficiency (continuity) of the electrospinning process. 10% PAV solns. contg. 0.1, 0.2 or 0.3% AgNO3 were also tested to obtain a nonwoven fabric with potential bactericidal activity against three different bacterial strains: Bacillus subtilis, Staphylococcus aureus and Acinetobacter baumannie. The most effective inhibition of bacterial growth by the obtained materials was obsd. in the case of S. aureus and A. baumannii, which are known pathogens from the “ESCAPE” group, i.e. those that are not subject to classical antibiotic therapy.

4

Electrospun openwork structures for applications in environmental engineering

Borowczak Maciej, Sobczyk Karolina, Leluk Karol

Polimery

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2024

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Vol. 69, nr 6

350--356

EN

The article presents the possibilities of producing fibrous structures using electrospinning from polymer solutions based on PBS and a binary solvent system. The main component of the system was chloroform. Dimethyl sulfoxide (DMSO) or N,N-dimethylformamide (DMF) was used as an additional solvent to increase the boiling point of the system. The influence of process parameters on the structure of the obtained fibers was described. The results were compared with those obtained using the extrusion blow molding method. The developed fibers will be used in air filtration processes.

PL

W artykule przedstawiono możliwości wytwarzania struktur włóknistych techniką elektroprzędzenia z roztworów polimerowych na bazie PBS i binarnego układu rozpuszczalników. Głównym składnikiem układu był chloroform. Sulfotlenek dimetylu (DMSO) lub N,N-dimetyloformamid (DMF) stosowano jako dodatkowy rozpuszczalnik w celu zwiększenia temperatury wrzenia układu. Opisano wpływ parametrów procesu na strukturę otrzymanych włókien. Wyniki porównano z wynikami uzyskanymi metodą wytłaczania z rozdmuchiwaniem. Opracowane włókna znajdą zastosowanie w procesach filtracji powietrza.

5

Biocompatibility of electrospun PVA-based nanocomposite with chemical vapor deposition-derived graphene monolayer

Sasmazel Hilal Turkoglu, Alazzawi Marwa, Sadhu Verra, Gozutok Melike

Polimery

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2024

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Vol. 69, nr 11-12

657--667

EN

The biocompatibility of electrospun PVA with monolayer graphene obtained by chemical vapor deposition (PVA/CVD-grown MLG) nanocomposite was investigated. The properties of PVA/ CVD-grown MLG nanocomposite were compared with those of electrospun PVA mat. Raman analysis confirmed the presence of graphene monolayer on PVA. Although no significant changes in tensile properties were observed, the electrical conductivity increased from 0.1 (PVA mat) to 0.4 μS/cm (PVA/ CVD-grown MLG). Thermal stability was also increased, as evidenced by the higher onset temperature and temperature of maximum decomposition rate determined by TGA. The contact angle decreased slightly, which resulted in higher PBS absorption and degradation of the nanocomposite. Water vapor transmission rate (WVTR) decreased from 40 (PVA mat) to 37 g/m2 h (PVA/CVD-grown MLG). Cell culture studies showed better cell viability, population, and growth in the case of PVA/CVD-grown MLG nanocomposite due to improved physical, chemical and mechanical properties.

PL

Zbadano biokompatybilność nanokompozytu elektroprzędzonego PVA i monowarstwowego grafenu otrzymanego metodą chemicznego osadzania z fazy gazowej. Właściwości nanokompozytu porównano z właściwościami elektroprzedzonej maty PVA. Analiza Ramana potwierdziła obecność monowarstwy grafenu na PVA. Pomimo, że nie stwierdzono istotnych zmian właściwości mechanicznych przy rozciąganiu, to przewodnictwo elektryczne wzrosło z 0,1 (mata PVA) do 0,4 μS/cm (nanokompozyt). Zwiększyła się również stabilność termiczna, o czym świadczy wyższa temperatura początku rozkładu i maksymalnej szybkości rozkładu oznaczona metodą TGA. Nieznacznie zmniejszył się kąt zwilżania, co skutkowało większą absorpcją PBS i degradacją nanokompozytu. WVTR zmniejszył się z 40 (mata PVA) do 37 g/m2•h (nanokompozyt). Ponadto ze względu na lepsze właściwości fizyczne, chemiczne i mechaniczne nanokompozytu uzyskano większą żywotność, populację i wzrost komórek.

6

Electrospun carbon nanofibers (CNFs) modified with needle-like SiC nanostructures

Pazdyk-Słaby Weronika, Długoń Elżbieta, Zientara Dariusz, Fraczek-Szczypta Aneta

Chemical and Process Engineering : New Frontiers

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2024

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Vol. 45, nr 3

art. no. e74

EN

Electrospun carbon nanofibers (CNFs) are an excellent material which can possess a wide range of properties through controlling the parameters of the electrospinning process, as well as through thermal treatment. At the same time, CNFs are an excellent substrate for carrying out modifications, both volumetric, at the stage of precursor preparation, and surface modifications. Different methods of introducing various silicon carbide (SiC) precursors into the spinning solution enables the formation of needleshaped SiC nanostructures on the CNF surface. This work presents an attempt to obtain nanofibrous carbon materials modified in volume and on the surface with SiC precursors, along with their characteristics. The most promising method of creating needle-like SiC nanostructures on the surface of CNFs is the use of volume modification with polysiloxane and silanization of the surface of the CNFs in a organosilicon sol solution.

7

Titania Nanoparticles Doped Electrospun Membranes

Madenli Evrim Celik, Ciftci Z. Ilkay

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 1

347--352

EN

Electrospun membranes exhibit very promising properties, such as high surface area, high surface area-to-pore volume ratio, high pore interconnectivity, and uniform pore distribution. Nanoparticles are a promising alternative for improving the properties of the electrospun membranes. Titania nanoparticles, which are stable, resistant, and non-toxic, have various applications including water treatment, sensors, food additive and cosmetics. Due to the high hydrophilicity of titania nanoparticles, membrane fouling is reduced in titania nanoparticles doped membranes. Titania nanoparticle doped polyacrylonitrile (PAN) nanocomposite electrospun membranes were prepared by electrospinning method in this work. Compared to bare PAN electrospun membranes 0.05% titania nanoparticles doped electrospun membranes have thinner nanofibers, higher hydrophilicity and almost 2 times lower bovine serum albumin adsorption, which shows lower fouling tendency.

8

Synthesis of Molybdenum Oxide Nanofibers with Multiple Surface Facets Via Electropsinning Followed by Rapid Thermal Treatment

Ryu Cheol-Hui, Lee Young-In

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 2

493--496

EN

A MoO3 nanofiber prepared by electrospinning and subsequent heat treatment is attracting significant attention due to its structural advantages. Vibrant studies are being conducted to control its morphology and diameter to improve its properties. In this study, we demonstrated the synthesis of α-MoO3 nanofibers with multiple surface facets by controlling the heating rate and temperature in the heat treatment step for removing polymer and crystallizing MoO3 from the electrospun polymer/precursor nanofibers. The analysis results show that the faster heating rate and higher heat treatment temperature in the thermal treatment process are more favorable for forming a shape in which particles with facet planes are connected. Finally, we observed the morphological change according to the heat treatment time to confirm the effect of the heat treatment conditions on the shape of MoO3 and interpreted the results in terms of nucleation and crystal growth.

9

Study of morphology and optical properties of novel Se-doped SnO2 1D nanostructures prepared by electrospinning

Smok W.

Archives of Materials Science and Engineering

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2024

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Vol. 129, nr 2

60--66

EN

Purpose: The paper aimed to manufacture novel SnO2:Se4+ nanostructures using a two-step electrospinning method followed by calcination at 500°C and to investigate its morphology, structure, chemical composition and optical properties. Design/methodology/approach: Nanostructures prepared by electrospinning and calcination were analysed for morphology and structure using scanning and transmission electron microscopy. The chemical and phase composition of the obtained nanomaterials was analysed using X-ray diffraction and the following spectroscopic methods: X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy. The UV-Vis spectrophotometer allowed us to analyse the range of electromagnetic radiation absorbed by the nanowires SnO2:Se4+ and determine their optical band gap. Findings: The electrospinning method followed by calcination successfully produced impurity-free, homogeneous, polycrystalline one-dimensional SnO2 nanostructures doped with Se4+ with an average diameter of 140 nm. Analysis of the optical properties of the manufactured nanostructures showed that their maximum absorption is in the middle and near-ultraviolet. The fabricated SnO2:Se4+ nanowires were characterized by a much lower optical band gap than undoped nanowires, increasing their application potential. Research limitations/implications: The work is a basis for further research on the effect of doping SnO2 nanostructures with nonmetal ions, in which, in the future, special attention should be paid to the influence of the manufacturing process parameters on the structure, morphology and optical and electrical properties of nanostructures. Practical implications: The favourable optical properties of spun SnO2:Se4+ nanowires give them great application potential in photocatalysis and the construction of modern photovoltaic cells and optoelectronic devices. Originality/value: In the given work, for the first time, a method of manufacturing Se4+-doped SnO2 nanowires using the electrospinning method followed by calcination was presented, and their morphology, structure, and optical properties were characterized. The presented study may provide valuable knowledge for the further development of semiconductor nanomaterials, which play a key role in developing fields such as gas sensing, communication, and renewable energy.

10

Regulation of N-type In2O3 Content on the Conductivity Typeof Co3O4 Based Acetone Sensor

Fu Lijuan, Fan Shuxing, Wang Zhao, Tang Wei

Materials Science Poland

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2023

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Vol. 41, No. 1

202--213

EN

A double-jet electrospinning method was adopted to fabricate In2O3/Co3O4 nanofibers (NFs). The sensitivity of In2O3/Co3O4NFs and In2O3NFs were compared and analyzed, and the morphology, structure, chemical composition, and gas-sensing properties of the samples were comprehensively characterized. The results show that the introduction of Co3O4can improve the response of In2O3/Co3O4to acetone, to 29.52 (In2O3/Co3O4) and 12.34 (In2O3) to 200 ppm acetone at 2000°C, respectively. In addition, the doping of Co3O4was found to reduce the optimum working temperature of pure In2O3 from 275°C to 200°C. The composite of Co3O4and In2O3not only enhances the sensing performance, but also leads to a conversion of p-n conductivity type. The phenomenon of the p-n transition is relevant to operating temperature and proportion of In2O3and Co3O4. While the enhanced acetone sensing properties of In2O3/Co3O4NFs may be attributed to the p-n hetero-junction between n-type In2O3 and p-type Co3O4 crystalline grains, which promotes the electron migration. The synergistic effects between In2O3and Co3O4and the large specific surface area of NFs additionally contribute to the improvements of acetone sensing performance.

11

Investigation of the Effect of Needle Diameter and the Solution Flow Rate on Fiber Morphology in the Electrospinning Method

Gündüz Gonca Şimşek

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 4

22--29

EN

In the study, the morphological properties of polyacrylonitrile (PAN) fibers produced by electrospinning at different needle diameters and solution flow rates were investigated. For this purpose, 20G and 22G diameter needles were used. The fibres were produced at flow rates of 0.5 ml/hr, 1 ml/hr and 1.5 ml/hr. Scanning electron microscopy (SEM) was used to measure nanofiber diameters. Statistical analyzes were made with the help of the SPSS program. It was observed that finer fibers were obtained as the needle diameter decreased. As the solution flow rate increased, thicker fibers were obtained. In addition, it was observed that the needle diameter and flow rate affect the fiber arrangement and interfiber spacing.

12

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.

13

PAN-Based Carbon Fibers Deposition on NiTi Surface

Goryczka Tomasz, Szaraniec Barbara, Stodolak-Zych Ewa, Kluska Stanisława

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

1109--1114

EN

The main objective of the work was to create a layer of carbon nanofibre on the surface of the NiTi shape memory alloy. The coating process was carried out in three stages. First, polyacrylonitrile was deposited by electrospinning. Then it was stabilized at temperatures up to 250°C. The last stage was the carbonization performed below 1000°C. The microstructure of the obtained coatings was observed using a scanning electron microscope. The X-ray diffraction techniques were applied to analyze the coating structure. After the polyacrylonitrile deposition, the fibers had an average diameter of about 280 nm, and the final fibers were almost twice as tiny. The applied steps also changed the phase and crystalline state of the fibers, finally leading to the formation of amorphous-nanocrystalline graphite.

14

Adipose derived stem cells and ginkgo biloba extract-loaded PCL/gelatin nanofibrous scaffolds for peripheral nerve injury repair: The impact of physical activity

Gong Hua, Chen Zhengtian

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 4

35--47

EN

Peripheral nerve damages take place as a result of trauma, compression, or disease, resulting in sensory loss, impaired motor function, and subsequent challenges. In the current study, ginkgo biloba extract was loaded into PCL/gelatin scaffolds through electrospinning method. The scaffolds were characterized in vitro using various studies. The prepared nanofibrous scaffolds were rolled up to make neural guidance channels. Then, the conduits were seeded with adipose derived stem cells and transplanted into a rat model of sciatic nerve injury. The scaffolds were not toxic and had optimal tensile and suturability. The animals treated with the conduits that delivered adipose derived stem cells and ginkgo biloba extract and received the treadmill exercise had significantly higher motor and sensory functions recovery. In addition, histopathological examinations showed beneficial role of the exercise plan on the nervous system repair.

15

Production of pumice-containing nanofibers by electrospinning technique

Kılıçer Ali

Materials Science Poland

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2022

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Vol. 40, No. 2

206--213

EN

The scope of the study involves identifying the optimal means to effectively use the electrospinning technique to obtain pumice-containing nanofibers. Nanofiber containing pumice in a solution was electrospun to obtain smooth, cylindrical, bead-free, and ultrafine nanomaterials. The study also analyzed the molecular [Fourier transform infrared spectroscopy (FTIR)], thermal [differential scanning calorimetry (DSC)], zeta potential, size, polydispersity index [dynamic light scattering (DLS)], and surface [scanning electron microscope (SEM)] parameters of the pumice-containing nanofibers having JP6 (applied voltage: 6 kV) and JP12 (12 kV) properties. While the distance (10 cm), flow rate (0.8 mL/h), and other parameters of the electrospinning process were fixed, two different voltages were applied to obtain the pumice-containing nanofiber. The average diameter of the nanoencapsulated pumice produced at 6 kV was defined as 98.6 nm in gelatin nanomats with 31.8 nm. The average diameter of the nanocapsule pumice produced under a 12 kV voltage was found to be 85.8 nm, and the average diameter of the nanomats (non–nanoencapsulated) was 35.2 nm. The average zeta potential values of the pumice-containing nanofiber were also determined in the nanosize range. The JP6 and JP12 PDI values were determined as 0.165 and 0.566, respectively. Peaks characteristic of pumices as defined in the literature were observed in the FTIR results, while DSC analysis results revealed strong endo- and exothermic peaks. As a result of this study, it has been proved that pumice can be reduced to nanosize with the electrospinning technique and it is nanoencapsulated in nanofiber. When the obtained pumice-containing nanofiber was examined, it was determined that the surface area of the nanofiber was large and resistant to thermal heat.

16

Fabrication of heterojunction MnTiO3–TiO2-decorated carbon nanofibers via electrospinning as an effective multifunctional photocatalyst

Yousef Ayman

Materials Science Poland

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2022

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Vol. 40, No. 2

289--305

EN

In this paper, we successfully synthesized heterojunction manganese titanate/titanate nanoparticles (MnTiO3–TiO2 NPs)-decorated carbon nanofibers (CNFs) employing the electrospinning process. The morphology, crystallinity, and chemical composition of the MnTiO3–TiO2-decorated CNFs is characterized via SEM, FESEM, STEM, TEM EDX, and XRD techniques. The synthesized nanocomposite exhibits good performance for photodegradation of methylene blue (MB) dye and hydrolysis of ammonia–borane complex for hydrogen releasing experiment in a batch reactor under visible light. A mathematical model was developed to predict the photocatalytic activity of the produced nanocomposite with various parameters. The operational parameters include the effect of the initial concentration, catalyst dosage, light intensity, and reaction temperature, which are studied to validate the mathematical model. The reaction rate constant of MB photodegradation is found to be 0.0153 min−1 for an initial MB concentration of 5 mg·L−1 with a catalytic dosage of 200 mg·L−1 at a reaction temperature of 25°C under a light intensity of 25 W·m−2. Similarly, the H2 generation employing TiO2@CNFs and MnTiO3–TiO2@CNFs under visible light irradiation is observed to be 0.31 mol and 2.95 mol, respectively, corresponding to an exposure of 10 min. We also demonstrated that the yield of hydrogen employing MnTiO3–TiO2@CNFs under visible light increases to 2.95 mol compared with 1.51 mol in darkness. Finally, comparisons were made between the experimental and model-predicted values of the reaction rate constant and final concentrations. Theoretical and experimental data of photocatalytic activity are found to be in good agreement for MnTiO3–TiO2@CNFs.

17

Vascular stents - materials and manufacturing technologies

Malisz Klaudia, Świeczko-Żurek Beata

Engineering of Biomaterials

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2022

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vol. 25, no. 166

22--28

EN

The objective of this article is to present materials and technology for the manufacture of vascular stents with appropriate design requirements. The use of the right material is very important in implantology. A biomaterial introduced into the circulatory system must be biocompatible and hemocompatible. At the same time, it should not initiate toxic, mutagenic, or immunological reactions. Currently, 316L stainless steel (316L SS), nitinol (Ni-Ti alloy) and cobalt-chromium alloy (Co-Cr) are used as standard stent materials. Additionally, drug-containing coatings are used to provide antithrombotic properties. Nowadays, scientists are trying to create biodegradable stents (BDS) using magnesium (Mg) or zinc (Zn) alloys. Laser methods are generally used to manufacture stents using Nd:YAG lasers with a pulse length in the range of several milliseconds. Material removal is based on the ejection of the melt using a high-pressure gas. The result is remelting and heat-affected zones. Various post-processing procedures are necessary to remove residues, including etching and electropolishing. Minimizing the heat-affected zone could be achieved by using femtosecond lasers. Additionally, immersion of the material in water prevents the deposition of residues on the workpiece. Interesting alternatives used in the manufacture of vascular stents are electrospinning or additive techniques. 3D printing enables obtaining of geometrically complex and personalized implants and reduces the consumption of materials and the production of waste.

18

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.

19

Simple synthesis of Black TiO2 Nanofibers Via Calcination in Inert Atmosphere

Ji Myeongjun, Kim Eung Ryong, Park Mi-Jeong, Jeon Hee Yeon, Moon Jaeyun, Byun Jongmin, Lee Young-In

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1481--1486

EN

Black TiO2 nanofibers have recently emerged as a promising material that has both advantages of black metal oxide and one-dimensional nanostructure. However, current reduction-based synthesis approaches are not compatible with practical applications because these processes require high process costs, complicated processes, and sophisticated control. Therefore, it is still necessary to develop a simple and facile method that can easily introduce atomic defects during the synthesis process. This work suggests an electrospinning process with an antioxidant and subsequent calcination process for the facile synthesis of black TiO2 nanofibers. The synthesized black TiO2 nanofiber has an average diameter of 50.3 nm and a rutile structure. Moreover, this nanofiber represented a noticeable black color and a bandgap of 2.67 eV, clearly demonstrating the bandgap narrowing by the introduced atomic defects.

20

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

|

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%).