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1.
Fabrication and characterization of electrospun nanofibers of high DP natural cotton lines cellulose
Chaorong Li Rui Chen Xiaoqiang Zhang Jie Xiong Yingying Zheng Wenjun Dong 《Fibers and Polymers》2011,12(3):345-351
Nanofibers of natural cotton lines cellulose, with a degree of polymerization above 10000, were prepared by electrospinning. The effects of cellulose concentration, flow rate and electric field strength on the morphologies of the fibers were systematically investigated. Furthermore, two effective improvements on the electrospinning apparatus were made: heating the pathway between the tip of the needle and the collector instead of the needle or the collector, and covering the drum with activated cellulose flake. High quality cellulose nanofibers were obtained under the optimized spinning conditions combined with the apparatus improvements. Moreover, oriented cotton nanofibers were acquired by elevating the rotation speed of the drum collector. The wettability of the nonwoven was greatly improved compared with the original activated cellulose. The obtained nonwoven or nanofibers of the natural cotton cellulose could be potentially applied in tissue scaffolds, protective clothing and high efficient water absorbing materials etc. 相似文献
2.
Yibing Cai Dawei Gao Qufu Wei Huili Gu Shi Zhou Fenglin Huang Lei Song Yuan Hu Weidong Gao 《Fibers and Polymers》2011,12(1):145-150
In this work, the pure polyacrylonitrile (PAN) nanofibers and PAN/FeCl3 composite nanofibers were prepared by an electrospinning process. Electrospinning solution properties including viscosity,
surface tension and conductivity, had been measured and combined with the results of Scanning electron microscopy (SEM), Atomic
force microscope (AFM) and Micro Combustion Calorimeter (MCC) to investigate the effects of FeCl3 on the structure, surface morphology and combustion property of electrospun PAN nanofibers, respectively. It was found from
SEM images that the diameters of composite nanofibers were decreased with the addition of FeCl3, which was attributed predominantly to the increased conductivity of the polymer solutions compared to viscosity and surface
tension. The AFM analyses revealed that the surface morphology of electrospun nanofibers changed from smooth and wrinkle-like
structure (without FeCl3) to rough and ridge-like structure (with FeCl3). The results characterized by MCC showed that the loading of FeCl3 decreased the heat release rate (HRR) and improved the combustion property of composite nanofibers. 相似文献
3.
Polymer organic-inorganic hybrid nanofibers constitute a new class of materials in which the polymeric nanofibers are reinforced
by uniformly dispersed inorganic particles having at least one dimension in nanometer-scale. In the present study, polyacrylonitrile
(PAN) and PAN/Na-montmorillonite (PAN/Na-MMT) nanofibers were conducted via electrospinning process. Electrospun PAN and PAN/Na-MMT
fibers with the respective mean fiber diameter of about 220 and 160 nm were prepared. The influence of the clay-montmorillonite
on the morphology and diameter of nanofibers was investigated by scanning electron microscope (SEM) and transmission electron
microscope (TEM) techniques. The microscopic techniques propose that the PAN/Na-MMT composite nanofibers show lower mean fiber
diameter than the neat PAN nanofibers. Besides, the difference in nanoclay-content has a slight effect on the distribution
of fibers diameter. Thermogravimetric analysis (TGA) results suggest that introduction of clay-nanomaterials improves the
thermal characteristics of fibers. 相似文献
4.
An allometrical scaling relationship between the diameter of electrospun nanofiber and solution concentration is established,
the scaling exponent differs greatly between different polymers and the same polymer with different molecules or the same
molecules with different properties. The diameter of electrospun polyacrylonitrile (PAN) nanofibers increases approximately
linearly with solution concentration. 相似文献
5.
Various shapes of ZnO — multi-petals, rod and spherical — were prepared and then applied on cotton fabric for UV-blocking
and anti-bacterial properties. The ZnO particles were investigated by XRD and SEM. The as-prepared suspension was applied
onto cotton fabrics via the pad-dry-cure process at 150 °C. The characteristics of the fabric coating were investigated by
SEM, XRD and Atomic Absorption Spectroscopy (AAS). The UV-blocking effectiveness was measured with a UV-Vis spectrophotometer
whilst the antibacterial activity was determined using the AATCC 147 method. The results of XRD and SEM on the ZnO powders
show that we can produce various shapes of ZnO. The investigation by SEM and AAS clearly revealed that ZnO was effectively
deposited on the cotton surface and that the adhesion was retained after washing ten cycles. The sphericals-shaped ZnO and
multi-petals shaped ZnO coated fabrics show excellent UV-blocking properties. All treated samples showed good antibacterial
activity against Staphylococcus Aureus. The shape of ZnO shows no considerable effect on antibacterial properties. 相似文献
6.
Layered fabric systems with electrospun polyurethane fiber web layered on spunbonded nonwoven were developed to examine the
feasibility of developing protective textile materials as barriers to liquid penetration using electrospinning. Barrier performance
was evaluated for layered fabric systems, using pesticide mixtures that represent a range of surface tension and viscosity.
Air permeability and water vapor transmission were assessed as indications of thermal comfort performance. Protection performance
and air/moisture vapor transport properties were compared for layered fabric systems and existing materials for personal protective
equipment (PPE). Layered fabric systems with electrospun nanofiber web showed barrier performance in the range between microporous
materials and nonwovens used for protective clothing. Layered fabric structures with the web area density of 1.0 and 2.0 g/m2 exhibited air permeability higher than most PPE materials currently in use; moisture vapor transport was in a range comparable
to nonwovens and typical woven work clothing fabrics. Comparisons of layered fabric systems and currently available PPE materials
indicate that barrier/transport properties that may not be attainable with existing PPE materials could be achieved from layered
fabric systems with electrospun nanofibrous web. 相似文献
7.
Well-aligned PMIA nanofiber mats were fabricated by electrospinning and then hot-stretching along the fiber axis was used to improve the mechanical properties of nanofibers in this paper. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Differential scanning calorimetry (DSC) were used to characterize the morphology and properties of nanofibers. The results showed that the nanofibers became thinner and better alignment than the as-spun nanofibers after hotstretching, and the average diameter of the nanofibers decreased with the increasing of the tensile force. In the same time, hotstretching improved the crystallinity and T g of the as-spun PMIA nanofibers. The tensile strength and modulus of the hotstretched nanofiber mats peaked at ca.50 % and ca.196 % respectively at the tensile force of 12 N compared with the as-spun nanofiber mats. 相似文献
8.
Blended nanofiber webs of poly(L-lactic acid) (PLLA)/poly(L-lysine) (PLys) with a PLys content of up to 3 % were prepared using an electro-spinning process with trifluoroacetic acid
as the spinning solvent, and employed as a substrate for silicification. Silica formation on the surface of the PLLA/PLys
nanofibers was carried out by immersing the nanofiber webs in silicic acid solutions at various concentrations for different
times. The effects of the silicification conditions and PLys content on silicification were examined by scanning electron
microscopy, FT-IR, energy dispersive spectroscopy, and the increase in weight of the substrates. Although the amount of silica
formed on the PLLA nanofibers increased with increasing silicification time and silicic acid concentration, the uniformity
of the coated layer was not controlled. However, the incorporation of small amounts of PLys in the PLLA nanofibers increased
the amount and uniformity of the silica formed on the nanofibers. 相似文献
9.
In the paper, the membrane with aligned carbon nanofibers (CNFs) was prepared by electrospinning, stabilization and carbonization. The electrical conductivity of the membrane was examined. The effect of stabilization temperature and drum rotating speed on the conductivity of aligned CNFs membrane was discussed. The study on stabilization temperature showed that 250 °C was optimum parameter for preparing fibrous aligned CNFs membrane with uniform diameter, but 270 °C was benefit to fiber conglutination which could improve the electrical conductivity of the final CNFs membrane. The study on drum rotating speed showed that when drum rotating speed reached 2500 rpm, graphitic structures with parallel graphene sheets could be observed and 1000, 1500 and 2000 rpm CNFs membranes presented desirable conductivity with only 1.3 Ω·cm in the parallel directions and 2.0 Ω·cm in the perpendicular direction. 相似文献
10.
To develop waterproof breathable materials for diverse consumer applications, we used electrospinning to fabricate layered
fabric systems with varying composite structures. Specifically, we developed layered fabric structures based on electrospun
nanofiber webs with different levels of nanofiber web density, as well as different substrates and layer structures, and then
examined the breathability and waterproofness of the material. The breathability and waterproofness of the layered fabric
systems were compared with those of traditional waterproof breathable fabrics, including densely woven fabric, microporous
membrane laminated fabric, and hydrophilic nonporous polyurethane coated fabric. Different breathability and barrier performance
levels were achieved by varying the layer structure and substrates in the electrospun nanofiber web layered fabric systems.
The uniformity of the nanofiber web and lamination process also affected the barrier and comfort performances. The comparison
of waterproofness and breathability performances between the new materials and the traditional waterproof breathable materials
revealed that the layered structures based on electrospun nanofiber webs provide a higher level of resistance to water penetration
than densely woven fabrics and a higher degree of moisture vapor and air permeability than microporous membrane laminates
and coated fabrics, with a proper selection of layer structure, substrate fabric, and lamination process. 相似文献
11.
Remant Bahadur K. C. Kwan Woo Kim Shanta Raj Bhattarai Hak Yong Kim Duck Rae Lee 《Fibers and Polymers》2007,8(2):186-191
Electrospinning is a versatile process used to prepare micro- and nano- sized fibers from various polymer solution. Here,
we dealt with the variation in the morphology of nylon 6 electrospun nanofibers and their polymorphism depending on the type
and physical state of the collectors. SEM study showed that the fiber diameter was increased from 80 to 103 nm while it was
collected in water bath. Similarly the fiber diameter and bonding was increased 103 to 115 nm with the temperature whereas
it was linearly decreased 103 to 90 nm with the conductivity of the water bath. Spectroscopic analysis (FT-Raman, FT-IR) showed
that the polymorphism of nylon 6 depended on the types of collector (aluminum sheet and water bath). Nylon 6 electrospun nanofibers
display theγ-phase while collected in aluminum sheet andα-phase while collection in water bath. The extent of transformation fromγ- toα-phase was linearly increased with temperature and conductivity of the water bath. 相似文献
12.
RSM and ANN approaches for modeling and optimizing of electrospun polyurethane nanofibers morphology
Amir Rabbi Komeil Nasouri Hossein Bahrambeygi Ahmad Mousavi Shoushtari Mohammad Reza Babaei 《Fibers and Polymers》2012,13(8):1007-1014
This paper focused on using response surface methodology (RSM) and artificial neural network (ANN) to analyze polyurethane (PU) nanofibers morphology synthesized by electrospinning. The process was characterized in detail by using experimental design to determine the parameters that may affect the nanofibers morphology such as polymer concentration, a tip to collector distance and applied voltage. It was concluded that solution concentration plays an important role (relative importance of 79.85 %) against nanofibers diameter and its standard deviation. Based on the results, applied voltage has a different effect on the nanofiber diameter at low and high solution concentrations. Moreover, the tip to collector distance parameter has no significant impact on the average nanofiber diameter. The finest PU nanofiber (201 nm) was obtained from experimental under conditions of: 9 w/v% polymer concentrations, 12 cm tip to collector distance and 16 kV applied voltage. The results show a very good agreement between the experimental and modeled data. It was demonstrated that both models (specially, in case of neural network) are excellent for predicting diameter of PU nanofibers. Furthermore, numerical optimization has been performed by considering desirability function to access the region in design space that introduces minimum average diameter. 相似文献
13.
Elakkiya Thangaraju Natarajan Thirupathur Srinivasan Ramadhar Kumar Praveen Kumar Sehgal Sheeja Rajiv 《Fibers and Polymers》2012,13(7):823-830
The present work reports the preparation of Poly L-Lactide (PLLA) and Curcumin loaded Poly L-Lactide (CPLLA) nanofibers by electrospinning. A series of PLLA solution (12 wt %) and C-PLLA (12 wt % PLLA) solution containing Curcumin (0.5 wt % and 1 wt %)) were electrospun into nanofibers. SEM images showed the average diameter of PLLA and C-PLLA in the range of 50?C200 nm. The TEM images showed the dispersion of Curcumin on C-PLLA nanofibers. The XRD pattern indicated decreases of crystallinity with the increase in the amount of Curcumin. The characteristic peak of Curcumin was confirmed by FTIR. The TGA results showed the degradation of PLLA and C-PLLA close to 300 °C. The percentage porosity and the contact angle of PLLA were found to be 90.2 % and 115±3 ° with deionised water, respectively. The water uptake percentage was found to be 17.6 %. The percentage cumulative release of Curcumin at the end of 8th day for 0.5 and 1.0 wt % formulations was 81.4±1.3 and 86.7±1.7 % respectively. The in-vitro biological cytotoxicity studies were performed using C6 glioma cells and NIH 3T3 fibroblast by MTT assay and SEM analysis. 相似文献
14.
R. Nirmala Kyung Soo Jeon R. Navamathavan Mira Park Hak Yong Kim Soo-Jin Park 《Fibers and Polymers》2014,15(5):918-923
In this study, we describe the preparation and characterization of electrospun Nylon66 composite nanofibers incorporated with carbon nanotubes (CNT) fillers and silver nanoparticles. We have incorporated the composites in to Nylon66 nanofibers to enhance the characteristics of the resultant composite nanofibers. The resultant composite nanofibers were characterized by using field-emission scanning electron microscopy, energy dispersive X-ray analysis, high-resolution transmission electron microscopy, X-ray diffraction, and current-voltage (I–V) measurement analysis. The morphology of the composite nanofibers exhibited densely arranged mesh-like ultrafine nanofibers which were strongly bound in between the main fibers. From I–V characteristics, it was observed that the incorporation of CNT fillers and Ag nanoparticles in to electrospun Nylon66 composite nanofibers can be significantly enhanced the electrical properties. 相似文献
15.
This study is an attempt to investigate the feasibility of alkali pre-treatment to activate surface hydroxyl groups of cellulose fibers in order to enhance the deposition efficiency of silver nanoparticles (AgNPs) onto cotton fabrics. Cotton samples were pre-treated with various alkali solutions containing different earth metal hydroxides (LiOH, NaOH, and KOH). The as-prepared samples were then treated with aqueous silver nitrate followed by reduction treatment with aqueous ascorbic acid, which caused in situ formation of AgNPs on fiber surfaces. The surface structure of the fabrics was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis, and colorimetric data. The amount of silver was measured by using inductively coupled plasma-optical emission spectrometer (ICP-OES). Antimicrobial activity was measured against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. It was established that alkali pre-treatment had a substantial effect on the formation and adsorption of AgNPs on the fibers. Alkali pre-treated samples were homogeneously coated by AgNPs with high surface coverage. Alkali type had significant effect not only on the amount of AgNPs on the surface but also on its size. High antibacterial activity against both Gram-positive and Gram-negative strains was also demonstrated, even after 10 cycles washing. 相似文献
16.
17.
Long-term efficacy of aroma microcapsules on natural indigo-dyed cotton fabric was evaluated by objective and subjective tests. The fixation of aroma microcapsules was carried out by pad-dry-cure process on dyed cotton fabric. Mercerized cotton fabric was dyed with natural indigo obtained from Polygonum tintorium (via the modified Niram method) and subsequently padded with melamine-formaldehyde microcapsules containing aroma essential oil (natural source of a Chinese arborvitae 20-25 %). Softener was applied in the same (one-step) or sequential (two-step) padding bath. We confirmed that microcapsules were fixed on cotton fibers by SEM analysis. The addition of softener was not much effective for the fabric performances on softness or air permeability. All the colorfastness ratings were above 4/5 and the color difference was within the acceptable range of 1.62-2.08. The efficacy of fabric samples stored for 2 years was evaluated using the GC/MS-headspace technique and the samples stored for 0.5, 1.5, and 2.5 years were also evaluated in terms of aroma release by the human perception test. Bornyl acetate was confirmed as the main component of essential oil, which was continuously released by the microcapsule-treated fabric (D/MC) during storage for more than 2 years. In durability and human perception tests, the microcapsules on the cotton fabric were stable to laundering, rubbing, ironing, and light. 相似文献
18.
This research presents a simple way to enhance the anti-UV property of bamboo pulp fabric trough in situ synthesis of ZnO particles on the fabric. Bamboo Pulp Fabric was treated by immersion method in Zn(NO3)2 and multi-amide compound (RSD) aqueous solution under hydrothermal condition, then the ZnO particles were grown on the surface of bamboo pulp fabric by in-situ method. In this synthesis RSD was applied as a stabilizer, reactant and dispersant agent, the reaction mechanism was investigated. The ZnO particles were characterized by transmission electron microscope (TEM), Xray diffraction (XRD) and ultraviolet/visible light spectrophotometer. The anti-UV property of Bamboo Pulp Fabric was characterized by measuring its UPF. The results indicated that the diameter of ZnO is about 150 nm, the length is about 600 nm. The Bamboo Pulp Fabric treated with ZnO particles showed good anti-UV property and its UPF can reach to 83.59. After washing for 20 times, it can also keep good anti-UV property. 相似文献
19.
20.
Saminathan Ratnapandian Stanley MacArthur Fergusson Lijing Wang 《Fibers and Polymers》2012,13(2):206-211
Coloration of textiles, traditionally achieved using natural dyes, commonly employs synthetic dyes at the industrial level.
A revival of commercial interest in natural dyes has opened several research avenues. This paper investigates the application
by padding of cotton fabric with 10 g/l of two natural dyes derived from the Acacia plant family. Three mordanting techniques were studied; of which post-mordanting
produced the most even shade. Among the two mordants investigated, the use of copper sulfate resulted in a level beige shade
at 15 g/l concentration while ferrous sulfate performed best at 5 g/l yielding a yellow-grey shade. An optimum process-sequence for the copper sulfate mordant was “pad (dye)→dry→steam followed
by pad (mordant)→steam→dry”, and for ferrous sulfte it was “pad (dye)→steam→dry followed by pad (mordant)→steam→dry”. Typically
a change in mordant resulted in a different shade with the same dye. The study concluded that padding is a readily adaptable
process for the dyeing of cotton using natural dyes and acceptable fastness in shades can be obtained. 相似文献