Highly solvent-stable polyimide ultrafine fibrous membranes fabricated by a novel ultraviolet-assisted electrospinning technique via organo-soluble intrinsically negative photosensitive varnishes

Magnetoresponsive polymer-based fibrous nanocomposites belonging to the broad category of stimuli-responsive materials, is a relatively new class of “soft” composite materials, consisting of magnetic nanoparticles embedded within a polymeric fibrous matrix. The presence of an externally applied magnetic field influences the properties of these materials rendering them useful in numerous technological and biomedical applications including sensing, magnetic separation, catalysis and magnetic drug delivery. This study deals with the fabrication and characterization of magnetoresponsive nanocomposite fibrous membranes consisting of methacrylic random copolymers based on methyl methacrylate (MMA) and 2-(acetoacetoxy)ethyl methacrylate (AEMA) (MMA-co-AEMA) and oleic acid-coated magnetite (OA·Fe3O4) nanoparticles. The AEMA moieties containingβ-ketoester side-chain functionalities were introduced for the first time in this type of materials, because of their inherent ability to bind effectively onto inorganic surfaces providing an improved stabilization. For membrane fabrication the electrospinning technique was employed and a series of nanocomposite membranes was prepared in which the polymer content was kept constant and only the inorganic (OA·Fe3O4) content varied. Further to the characterization of these materials in regards to their morphology, composition and thermal properties, assessment of their magnetic characteristics disclosed tunable superparamagnetic behaviour at ambient temperature.

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An Investigation into Hydraulic Permeability of Fibrous Membranes with Nonwoven Random and Quasi-Parallel Structures

Membranes ◽

10.3390/membranes12010054 ◽

2021 ◽

Vol 12 (1) ◽

pp. 54

Author(s):

Zeman Liu ◽

Yiqi Wang ◽

Fei Guo

Keyword(s):

Flow Rate ◽

Fiber Diameter ◽

Hydraulic Permeability ◽

Random Structure ◽

Electrospinning Technique ◽

Hydraulic Flow ◽

Parallel Structures ◽

Fiber Arrangement ◽

State Models ◽

Fibrous Membranes

Fibrous membranes with a nonwoven random structure and a quasi-parallel fibrous structure can be fabricated by the electrospinning technique. The membranes with different structures exhibited different behaviors to a hydraulic flow passing through the membranes. This work presents the effects of the fiber arrangement, fiber diameter, and deformations of the fibers on the hydraulic permeability. The results showed that the hydraulic flow can generate an extrusion pressure which affects the porosity and pore structure of the fibrous membranes. The quasi-parallel fibrous membranes and nonwoven membranes exhibited similar variation tendencies to the change of the experimental variables. However, the quasi-parallel fibrous membranes exhibited a higher sensibility to the change of the hydraulic flow rate. The hydraulic permeability of the quasi-parallel fibrous membranes was further analyzed with packing state models in this work.

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Develop Flexible Piezoelectric PVDF Nano-Fibrous Membrane

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.465 ◽

2011 ◽

Vol 675-677 ◽

pp. 465-468 ◽

Cited By ~ 2

Author(s):

Yong Rong Wang ◽

Pei Hua Zhang ◽

Chun Ye Xu

Keyword(s):

Polyvinylidene Fluoride ◽

Ferroelectric Properties ◽

Tactile Sensor ◽

Fibrous Membrane ◽

Diameter Distribution ◽

Pvdf Film ◽

Tactile Sensors ◽

Electrospinning Technique ◽

External Impact ◽

Fibrous Membranes

Piezoelectric polymer, polyvinylidene fluoride (PVDF) film, has been widely investigated as sensor and transducer material due to its high piezo-, pyro-, and ferroelectric properties. However, there are many limitations for PVDF film as human-related tactile sensor, such as non-breathability, stretching, requirement of additional process like poling, etc. In this paper, PVDF nano-fibrous membrane which is light, flexible, and wearable was prepared by electrospinning technique. The electrospinning parameters such as the voltage, feeding rate, tip-tocollector distance, etc, were well controlled. More than 4 hours electrospinning time was needed for a certain thickness of PVDF nano-fibrous membrane. The morphology of PVDF nanofiber was determined by scanning electron microscopy (SEM), the diameter distribution was calculated and crystal structure was evaluated by FTIR spectroscopy. We found the feasibility of developing piezoelectric PVDF fibrous membranes through electrospinning technology, which is a good candidate for flexible human-related tactile sensors to sense garment pressure, blood pressure, heartbeat rate, accidental external impact on human body, etc.

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Encapsulation of Diclofenac Molecules into Poly(-Caprolactone) Electrospun Fibers for Delivery Protection

Journal of Nanomaterials ◽

10.1155/2009/238206 ◽

2009 ◽

Vol 2009 ◽

pp. 1-8 ◽

Cited By ~ 23

Author(s):

Loredana Tammaro ◽

Giuseppina Russo ◽

Vittoria Vittoria

Keyword(s):

Diclofenac Sodium ◽

Composite Fibers ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Electrospinning Technique ◽

In Vitro Drug Release ◽

Good Thermal Stability ◽

Fibrous Membranes ◽

Poly Caprolactone

Mg-Al Hydrotalcite-like clay (LDH) intercalated with diclofenac anions (HTlc-DIC) was introduced into poly(-caprolactone) (PCL) in different concentrations by the electrospinning technique, and mats of nonwoven fibers were obtained and compared to the pristine pure electrospun PCL. The fibers, characterized by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry, show an exfoliated clay structure up to 3 wt%, a good thermal stability of the diclofenac molecules and a crystallinity of PCL comparable to the pure polymer. The scanning electron microscopy revealed electrospun PCL and PCL composite fibers diameters ranging between 500 nm to 3.0 m and a generally uniform thickness along the fibers. As the results suggested the in vitro drug release from the composite fibers is remarkably slower than the release from the corresponding control spun solutions of PCL and diclofenac sodium salt. Thus, HTlc-DIC/PCL fibrous membranes can be used as an antinflammatory scaffold for tissue engineering.

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Effects of Montmorillonite and Gentamicin Addition on the Properties of Electrospun Polycaprolactone Fibers

Materials ◽

10.3390/ma14226905 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6905

Author(s):

Ewa Stodolak-Zych ◽

Roksana Kurpanik ◽

Ewa Dzierzkowska ◽

Marcin Gajek ◽

Łukasz Zych ◽

...

Keyword(s):

Fibrous Composite ◽

Grain Morphology ◽

Nonwoven Fabric ◽

Interplanar Distance ◽

Electrospinning Process ◽

Release Time ◽

Electrospinning Technique ◽

Gentamicin Sulfate ◽

Gentamicin Sulphate ◽

Fibrous Membranes

Electrospinning was used to obtain multifunctional fibrous composite materials with a matrix of poly-ɛ-caprolactone (PCL) and 2 wt.% addition of a nanofiller: montmorillonite (MMT), montmorillonite intercalated with gentamicin sulphate (MMTG) or gentamicin sulphate (G). In the first stage, the aluminosilicate gallery was modified by introducing gentamicin sulfate into it, and the effectiveness of the intercalation process was confirmed on the basis of changes in the clay particle size from 0.5 µm (for MMT) to 0.8 µm (for MMTG), an increase in the interplanar distance d001 from 12.3 Å (for MMT) to 13.9 Å (for MMTG) and altered clay grain morphology. In the second part of the experiment, the electrospinning process was carried out in which the polymer nonwovens with and without the modifier were prepared directly from dichloromethane (DCM) and N,N-dimethylformamide (DMF). The nanocomposite fibrous membranes containing montmorillonite were prepared from the same polymer solution but after homogenization with the modifier (13 wt.%). The degree of dispersion of the modifier was evaluated by average microarray analysis from observed area (EDS), which was also used to determine the intercalation of montmorillonite with gentamicin sulfate. An increase in the size of the fibers was found for the materials with the presence of the modifier, with the largest diameters measured for PCL_MMT (625 nm), and the smaller ones for PCL_MMTG (578 nm) and PCL_G (512 nm). The dispersion of MMT and MMTG in the PCL fibers was also confirmed by indirect studies such as change in mechanical properties of the nonwovens membrane, where the neat PCL nonwoven was used as a reference material. The addition of the modifier reduced the contact angle of PCL nonwovens (from 120° for PCL to 96° for PCL_G and 98° for PCL_MMTG). An approximately 10% increase in tensile strength of the nonwoven fabric with the addition of MMT compared to the neat PCL nonwoven fabric was also observed. The results of microbiological tests showed antibacterial activity of all obtained materials; however, the inhibition zones were the highest for the materials containing gentamicin sulphate, and the release time of the active substance was significantly extended for the materials with the addition of montmorillonite containing the antibiotic. The results clearly show that the electrospinning technique can be effectively used to obtain nanobiocomposite fibers with the addition of nonintercalated and intercalated montmorillonite with improved strength and increased stiffness compared to materials made only of the polymer fibers, provided that a high filler dispersion in the spinning solution is obtained.

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PCL-ZnO/TiO2/HAp Electrospun Composite Fibers with Applications in Tissue Engineering

Polymers ◽

10.3390/polym11111793 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1793 ◽

Cited By ~ 4

Author(s):

Jinga ◽

Zamfirescu ◽

Voicu ◽

Enculescu ◽

Evanghelidis ◽

...

Keyword(s):

Tissue Engineering ◽

Point Of View ◽

The Body ◽

Electrospinning Technique ◽

Biological Assays ◽

Different Types ◽

Fibrous Membranes ◽

Fiber Fragmentation ◽

Precursor Powders ◽

Simulated Body Fluid Immersion

The main objective of the tissue engineering field is to regenerate the damaged parts of the body by developing biological substitutes that maintain, restore, or improve original tissue function. In this context, by using the electrospinning technique, composite scaffolds based on polycaprolactone (PCL) and inorganic powders were successfully obtained, namely: zinc oxide (ZnO), titanium dioxide (TiO2) and hydroxyapatite (HAp). The novelty of this approach consists in the production of fibrous membranes based on a biodegradable polymer and loaded with different types of mineral powders, each of them having a particular function in the resulting composite. Subsequently, the precursor powders and the resulting composite materials were characterized by the structural and morphological point of view in order to determine their applicability in the field of bone regeneration. The biological assays demonstrated that the obtained scaffolds represent support that is accepted by the cell cultures. Through simulated body fluid immersion, the biodegradability of the composites was highlighted, with fiber fragmentation and surface degradation within the testing period.

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Preparation and Characterization of Electrospun PVDF/PMMA Composite Fibrous Membranes-Based Separator for Lithium-Ion Batteries

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.1914 ◽

2013 ◽

Vol 750-752 ◽

pp. 1914-1918 ◽

Cited By ~ 2

Author(s):

Yin Zheng Liang ◽

Si Chen Cheng ◽

Jian Meng Zhao ◽

Chang Huan Zhang ◽

Yi Ping Qiu

Keyword(s):

Lithium Ion Batteries ◽

Vinylidene Fluoride ◽

Lithium Ion ◽

Attenuated Total Reflection ◽

Scanning Calorimetry ◽

Electrospinning Technique ◽

Poly Vinylidene Fluoride ◽

Fibrous Membranes ◽

Composite Fibrous Membranes

The poly (vinylidene fluoride)/poly (methyl methacrylate)(PVDF/PMMA) composite fibrous membranes with different blend ratio for use as separator of lithium-ion batteries have been developed by electrospinning technique. The surface morphology and crystal structure of electrospun PVDF/PMMA composite fibrous membranes are characterized using scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and differential scanning calorimetry (DSC).The results indicated that the addition of PMMA into PVDF increased the fiber diameter, decreased the crystalline of electrospun composite fibrous membranes and the good molecular level interaction between these two polymers were obtained. Meanwhile,electrospun PVDF/PMMA (90/10) composite fibrous membranes exhibited the highest ionic conductivity of 2.54×10-3S/cm at room temperature with electrochemical stability of up to 5.0V.

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Nanoporous PLA/(Chitosan Nanoparticle) Composite Fibrous Membranes with Excellent Air Filtration and Antibacterial Performance

Polymers ◽

10.3390/polym10101085 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1085 ◽

Cited By ~ 17

Author(s):

Hui Li ◽

Zhe Wang ◽

Haiyan Zhang ◽

Zhijuan Pan

Keyword(s):

Chitosan Nanoparticles ◽

Poly Lactic Acid ◽

Air Filtration ◽

Electrospinning Technique ◽

Air Filter ◽

High Antibacterial Activity ◽

Antibacterial Performance ◽

One Step ◽

Fibrous Membranes ◽

The One

Particulate matter (PM) pollution, which usually carries viruses and bacteria, has drawn considerable attention as a major threat to public health. In this present study, an environment-friendly antibacterial Poly(lactic acid)(PLA)/chitosan composite air filter was fabricated using the one-step electrospinning technique. The composite PLA/chitosan fibres show a highly porous structure, in which chitosan nanoparticles (NPs) were found to be uniformly distributed throughout the entire fibre. The morphologies, through-pore size and distribution, air filtration and anti-microbial properties of these filter media were studied. The results showed that it was not the chitosan content but instead the concentration of the spinning solutions that had the greatest effect on the morphologies of the porous fibres. The relative humidity influenced the nanometre-scale pores on the surface of PLA/chitosan fibres. The PLA/chitosan fibrous membranes with a chitosan to PLA mass ratio of 2.5:8 exhibited a high filtration efficiency of 98.99% and a relatively low pressure drop (147.60 Pa) when the air flow rate was 14 cm/s, while these also had high antibacterial activity of 99.4% and 99.5% against Escherichia coli and Staphylococcus aureus, respectively. It took 33 min for the PM2.5 concentration to decrease to 0 μg/m3 from 999 μg/m3 using the PLA/chitosan fibrous membranes, which demonstrates obviously effective air purification performance.

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