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1.
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
2.
Hui Qiao Yibing Cai Fang Chen Qufu Wei Foquan Weng Fenglin Huang Lei Song Yuan Hu Weidong Gao 《Fibers and Polymers》2009,10(6):750-755
The Fe-montmorillonite (Fe-MMT) combined catalysis effects of Fe ion with barrier effects of silicate clays, was firstly synthesized
by hydrothermal method, and then was modified by cetyltrimethyl ammonium bromide (CTAB). The organic-modified Fe-montmorillonite
(Fe-OMT) was dispersed in the N, N-dimethyl formamide (DMF) and then compounded with polyacrylonitrile (PAN) solution which
was dissolved in DMF. The composite solutions were electrospun to form PAN/Fe-OMT nanocomposite fibers. The influences of
the Fe-OMT on the structure, morphology, thermal, flammability and mechanical properties of PAN nanocomposite fibers were
respectively characterized by X-ray diffraction (XRD), High-resolution transmission electron microscopy (HRTEM), Scanning
electron microscopy (SEM), Thermogravimetric analyses (TGA), Micro Combustion Calorimeter (MCC) and Electronic Single Yarn
Strength Tester. It was found from XRD curves that there was not observable diffraction peak of silicate clay, indicating
that the silicate clay layers were well dispersed within the PAN nanofibers. The HRTEM image indicated that the multilayer
stacks of nanoclays could be found within the nanofibers and were aligned almost along the axis of the nanofibers. The SEM
images showed that the diameters of nanocomposite fibers were decreased with the loading of the Fe-OMT. The TGA analyses revealed
that the onset temperature of thermal degradation and charred residue at 700°C of PAN nanocomposite fibers were notably increased
compared with the pure PAN nanofibers, contributing to the improved thermal stability properties. It was also observed from
MCC analyses that the decreased peak of heat release rate (PHRR) of the PAN nanocomposite fibers reduced the flammability
properties. The loadings of Fe-OMT increased the tensile strength of PAN nanocomposite fibers, but the elongation at break
of PAN nanocomposite fibers was lower than that of the PAN nanofibers. 相似文献
3.
Eletriospinning process was used to fabricate Zirconia nanofibers and polyvinyl pyrrolidone (PVP) was employed in this procedure.
SEM, TGA, FT-IR and XRD were used to investigate the electrospinning process. Pure PVP was electrospun at the same conditions
as comparisons. The results indicated that the fibers had an average diameter about 80 nm with smooth surface. FT-IR spectrum
and TGA curve proved that PVP was removed from the fibers after a thermal treatment. It was found that the crystal structure
of Zirconia changed at different calcination temperature. The use of PVP, bicomponent solvent of water and ethanol and inorganic
salt had positive effects on the morphology of the fibers. 相似文献
4.
Alessandra Boschi Cristina Arosio Ilaria Cucchi Fabio Bertini Marinella Catellani Giuliano Freddi 《Fibers and Polymers》2008,9(6):698-707
Different silk substrates in form of spun silk tops, nonwoven web, yarn, and fabric were coated with electrically conducting
doped polypyrrole (PPy) by in situ oxidative polymerization from an aqueous solution of pyrrole (Py) at room temperature using FeCl3 as catalyst. PPy-coated silk materials were characterized by optical (OM) and scanning electron (SEM) microscopy, FT-IR spectroscopy,
and thermal analysis (DSC, TG). OM and SEM showed that PPy completely coated the surface of individual silk fibers and that
the polymerization process occurred only at the fiber surface and not in the bulk. Dendrite-like aggregates of PPy adhered
to the fiber surface, with the exception of the sample first polymerized in the form of tops and then spun into yarn using
conventional industrial machines. FT-IR (ATR mode) showed a mixed spectral pattern with bands typical of silk and PPy overlapping
over the entire wavenumbers range. DSC and TG showed that PPy-coated silk fibers attained a significantly higher thermal stability
owing to the protective effect of the PPy layer against thermal degradation. The mechanical properties of silk fibers remained
unchanged upon polymerization of Py. The different PPy-coated silk materials displayed excellent electrical properties. After
exposition to atmospheric oxygen for two years a residual conductivity of 10–20 % was recorded. The conductivity decreased
sharply under the conditions of domestic washing with water, while it remained essentially unchanged upon dry cleaning. Abrasion
tests caused a limited increase of resistance. PPy-coated silk tops were successfully spun into yarn either pure or in blend
with untreated silk fibers. The resulting yarns maintained good electrical properties. 相似文献
5.
Lei Chen Zhen Hu Lixin Xing Jie Wu Nan Zheng Li Liu Jinmei He Yudong Huang 《Fibers and Polymers》2014,15(6):1160-1167
A new application of conventional electroless nickel plating to improve the interfacial properties of PBO fibers was reported. The relationship between surface morphology and interfacial properties of nickel-plated PBO fiber was explored. The continuous nickel coating consisted of nickel and phosphorus elements determined by Energy dispersive spectrometer (EDS) and transmission electron microscope (TEM), exhibiting high adhesive durability. The influence of bath temperature and plating time on the crystal structure, microstructure and mechanical properties of nickel-plated PBO fibers was systematically investigated. X-ray diffractometer (XRD) results revealed that the crystal structure among nickel-plated PBO fibers did not show differences. Scanning electron microscope (SEM) and Atomic force microscope (AFM) images showed that the process parameters had a great influence on surface morphology and roughness of nickel-plated PBO fibers, which could directly affect the interfacial properties of nickel-plated PBO fibers. Single fiber pull-out testing results indicated that the interfacial shear strength (IFSS) of PBO fibers after electroless nickel plating had a significant improvement, which reached maximum at 85 °C for 20 min. Single fiber tensile strength of nickel-plated PBO fibers was slightly lower than that of untreated one. Thermo gravimetric analysis (TGA) indicated that nickel-plated PBO fiber had excellent thermal stability. 相似文献
6.
In this study, the surface of polyester fiber was modified by means of thermal treatment with a silver carbamate complex. We used scanning electron microscopy (SEM), an X-ray diffraction technique (XRD), and X-ray photoelectron spectroscopy (XPS) to allow a detailed characterization of the silver-coated polyethylene terephthalate (PET) fibers. The results revealed remarkable changes in the surface morphology and microstructure of the silver film after thermal reduction. On SEM, the silver nanoparticles (AgNPs) were seen to be uniformly and densely deposited on the fiber surface. The XRD pattern of the silver-coated fiber indicated that the film has a crystalline structure. A continuous layer of AgNPs, between 30 and 100 nm in size, was assembled on the PET fibers. The PET/Ag composite was found to impart high conductivity to the fibers, with an electrical resistivity as low as 0.12 kΩ·cm. 相似文献
7.
Necla Yaman 《Fibers and Polymers》2009,10(4):413-418
Organic-inorganic hybrid coatings containing phosphoric acid (PA) bonded to the organic-inorganic network were prepared from
tetraethoxysilane (TEOS) using a sol-gel process. The effect of sol-gel phosphate-based flame retardant coating on polyacrylonitrile
fabric properties (flammability, stiffness, and strength) was investigated. Sample characterization of the coated samples
were investigated using differential thermal/thermogravimetric analysis (DTA/TGA), Fourier transform infrared spectroscopy
(FTIR), X-ray diffractometer (XRD), and scanning electron microscopy (SEM). The results showed that hybrid coating on the
polyacrylonitrile fabrics influenced fabric stiffness, strength, and flammability. And also, flammability of the coated samples
after washing cycles was investigated, and the flame retardancy properties of the samples after 10 repeated washings were
not completely lost. 相似文献
8.
Jute fibers have immense potential to be used as natural fillers in polymeric matrices to prepare biocomposites. In the present study jute fibers were surface treated using two methods: i) alkali (NaOH) and ii) alkali followed by silane (NaOH+Silane) separately. Effects of surface treatments on jute fibers surface were characterized using fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyses. Further, the effects of surface treatments on jute fibers properties such as crystallinity index, thermal stability, and tensile properties were analyzed by X-ray diffraction method (XRD), thermo gravimetric analysis (TGA), and single fiber tensile test respectively. The effects of surface treatment of jute fibers on interphase adhesion between of poly(lactic acid) (PLA) and jute fibers were analyzed by performing single fiber pull-out test and was examined in terms of interfacial shear strength (IFSS) and critical fiber length. 相似文献
9.
Novel composite nanofibrous materials of poly(vinylidene fluoride) (PVDF) or poly(vinylidene fluoride-cohexafluoropropylene) (PVDF-HFP) and ZnO nanoparticles were prepared by conjunction of electrospinning and electrospraying techniques. Simultaneous electrospinning of concentrated solution of PVDF or PVDF-HFP and electrospraying of suspension of ZnO in diluted PVDF or PVDF-HFP solution enable the preparation of materials consisting of fibers on which ZnO was deposited on the fibers’ surface (design type “on”). These fibrous materials were compared with materials consisting of PVDF or PVDF-HFP fibers in which ZnO was incorporated in the fibers (design type “in”) and which were obtained by one-pot electrospinning of a suspension of ZnO nanoparticles in concentrated PVDF or PVDF-HFP solution. The fiber morphology and the presence of ZnO “in” or “on” the fibers were observed by scanning electron microscopy (SEM) and by transmission electron microscopy (TEM). The effect of the used technique on the type, size and shape of the obtained structures was discussed. The fibrous mats were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), contact angle measurements and mechanical tests as well. It was found that the decoration of fibers with ZnO resulted in increase of their thermal stability and hydrophobicity. The microbiological tests showed that the materials of design type “on” possessed strong antibacterial activity against the pathogenic microorganism Staphylococcus aureus. The results suggest that, due to their antibacterial activity, the obtained composite materials are suitable for wound dressing applications. 相似文献
10.
Polypropylene fabrics were coated with copper particles using electroless plating, screen printing and wire arc spray coating techniques. Surface morphology of the fabrics was studied using optical and scanning electron microscopes (SEM). Furthermore, tensile strength, electrical conductivity, thermal conductivity, air permeability, water contact angle and fog collection efficiency of the coated fabrics were measured and the obtained results were analyzed. SEM micrographs showed that a very thin and uniform layer of copper deposited on the surface of the electroless plated polypropylene fibers. In the printed or spray coated fabrics the copper particles filled the spaces between yarns and fibers. The polypropylene electroless copper plated fabrics showed higher tensile strength, electrical conductivity, air permeability and thermal conductivity when compared with the fabrics coated with copper screen printed and copper spray coated fabrics. Finally, the obtained results showed that copper electroless plating could increase the fog collection efficiency of polypropylene fabrics considerably. As a conclusion, the surface modified copper electroless polypropylene fabrics are good candidates for fog collection in appropriate regions which need further investigations. 相似文献
11.
Mohammad Abu Shayed Heike Hund Rolf Dieter Hund Chokri Cherif 《Fibers and Polymers》2016,17(2):229-240
Thermal and oxidation resistant coating is necessary for carbon fiber (CF) in CF reinforced concrete (CFRC) composite application in order to fulfil a high level of safety standard in case of fire. Pre-ceramic coatings such as Polysilazane, Polysiloxane, and Methyl silicone resin have been deposited on CF filament yarn by means of wet chemical continuous dip coating method. The surface analyses e.g. scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) results showed the changes of surface morphology by the coatings. Thermo gravimetric analysis (TGA) revealed that the high temperature (up to 800 °C) oxidation stability of CF was significantly improved with coatings. Thermo-mechanical properties also significantly enhanced up to 600 °C. CF yarn retains its original strength and elasticity modulus/stiffness at 700 °C due to thermal and oxidation resistant coatings. 相似文献
12.
Polyhydroxy butyrate-co-valerate (PHBV) ?? Zinc oxide (ZnO) nano composite fibers were prepared using electrospinning. The structural and optical properties were studied using Fourier transform infrared spectroscopy (FT-IR), Xray diffraction (XRD) and photoluminescence study (PL). The morphology observed with scanning electron microscope (SEM) revealed no significant changes in the nano composite fibers as compared to bare polymer. The low concentration of ZnO nanoparticles resulted in an increase in overall crystallinity of the polymer matrix which was confirmed from FT-IR and XRD results. The photoluminescence (PL) study indicated the quenching of visible emission in the composite fibers. The ratio of UV to visible emission (Iuv/Ivis) intensity was found to be 12.8 times enhanced in the composite fibers compared to bare ZnO nanoparticles. The nanofibrous mats are self supported and hence offer potential applications in optoelectronic devices and the biomedical imaging. 相似文献
13.
The chemical and morphological properties of ramie fibers treated by chemical surface modification were examined with Fourier
transform infrared (FT-IR) spectroscopy. The mechanical and thermal decomposition properties were evaluated with respect to
tensile strength, tensile modulus and thermogravimetric analysis (TGA). Surface morphological changes were investigated with
scanning electron microscopy (SEM). Finally, the capabilities of composites reinforced with various chemically treated fibers
were analyzed by investigating tensile and impact strengths. Additionally, the thermal mechanical properties of the composites
were investigated with thermal mechanical analysis (TMA). Based on the results of these analyses, we concluded that pectin,
lignin and hemicellulose were removed and thermal stability was increased with chemical treatments. The composites reinforced
with ramie fiber showed better properties compared with pure PLA matrix with respect to tensile and impact strengths. The
peroxide-treated fiber composite had the smallest thermal expansion. 相似文献
14.
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
15.
Sulfur-modified chitosan hydrogel (SMCH) was successfully synthesized by grafting dimethyl 3,3′-dithiodipropionate onto chitosan and then crosslinking with N,N′-methylene diacrylamide (MBA). The structure and properties of chitosan and sulfur-modified chitosan (SMC) were characterized and analyzed by Fourier transform infrared spectroscopy (FT-IR), Nuclear magnetic resonance (1H NMR), X-ray diffraction (XRD) and Thermogravimetric analysis (TGA). Meanwhile, chitosan hydrogel and SMCH were characterized by Scanning electron microscope (SEM). In addition, static adsorption Hg(II) ions properties of chitosan hydrogel and SMCH were also investigated. The FT-IR and 1H NMR manifested that SMC was synthesized successfully. The XRD and TGA showed that the crystallinity and thermal stability of SMC decreased. SEM showed that the SMCH had much more pores and bigger specific surface area than chitosan hydrogel. The result of adsorption experiment indicated that the SMCH showed noticeable improvements in the adsorption capacity of Hg(II), and had the highest adsorption capacity (187.5 mg/g) at pH 5.0. The equilibrium was achieved at 40 min. And the maximum adsorption capacities were 186.9 mg/g of SMCH. 相似文献
16.
In order to improve thermal stability of Acrylonitrile-butadiene-styrene (ABS) polymer, ABS/natural clinoptilolite (Clino) nanocomposite was produced using solvent/non-solvent method. The influence of natural clinoptilolite nanoparticles on scratch resistance and adherence properties of ABS coating on steel coupons was investigated. In order to study the scratch resistance and adherence properties, thin (20 µm) coatings of ABS and ABS/Clino nanocomposites, were prepared by solution casting method. The formation of ABS/Clino nanocomposite was characterized using FTIR spectroscopy, X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM). Results showed that there is a strong interaction such as hydrogen bonding between ABS and clinoptilolite nanoparticles. The thermal stability of the nanocomposite was examined using thermogravimetric analysis (TGA). TGA results showed an increase in the thermal degradation temperature of the nanocomposite. TGA results indicated that the thermal stability of ABS increases by increasing the Clino content of nanocomposite up to 5 % w/w. Scratch resistance and adherence properties of ABS/Clino nanocomposite coatings were also evaluated. Results showed that the scratch resistance and adherence strength of ABS/Clino nanocomposite coatings are higher than that of pure ABS coatings. 相似文献
17.
The coating modification of polyacrylonitrile (PAN) fibers with boric acid to enhance the controllability of thermally oxidative
stabilization process. The stabilization process, cross-section morphologies of oxidized and carbonized products were investigated
by means of optical microscopy, SEM, XPS and in-situ thermal shrinkage indicator. The results indicated that the coating with
boric acid on fiber surface was effective to avoid skin-core heterogeneity on the cross section and, in the stabilization
process, that boric acid as a crosslinking agent to tie together the adjacent oxidative molecular chains was confirmed. It
was suggested that the crosslinked structures should play an essential role in controlling the formation of uniform oxidized
structures, which is favorable for tensile properties of carbon fibers. 相似文献
18.
Structural transformations taking place during the thermal stabilization of polyacrylonitrile (PAN) fiber used for the production
of carbon fiber were characterized using a combination of polarized infrared spectroscopy, thermogravimetric analysis (TGA),
scanning electron microscopy (SEM), and density measurements. Direct relationship between the increasing oxygen content and
the density values was confirmed with increasing stabilization time. Linear density values were found to be directly influenced
by the stabilization time. Thermal stability of stabilized precursor fibers was evaluated in terms of weight loss and residual
weight fraction. The results showed that a residual weight fraction of 65 % at 1000 °C can be obtained but longer stabilization
time resulted in a loss of residual weight fraction due to excessive thermal degradation. SEM was used for the observation
of surface morphological features of stabilized precursor fibers. Polarized infrared spectroscopy showed the loss of molecular
orientation of methylene (CH2), nitrile (Ct=N), and carbonyl (C=O) groups in direct response to the effects of cyclization, dehydrogenation, and amorphization
(i.e. decrystallization) processes taking place during the stabilization stage. 相似文献
19.
Nanostructured silver thin films were sputtered onto the aromatic thermotropic liquid crystalline fibers of Vectran by magnetron
sputtering technology. Plasma treatment was used as pre-treatment in order to improve the deposition of the coating layer.
Surface morphology of the coated fibers was examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM).
A full energy dispersive X-ray analysis (EDX) was used to detect the elemental composition of the material. Its conductivity
and mechanical properties were measured and analyzed as well. The study revealed that a very thin conductive silver deposition
exhibited high electrical conductivity as well as less influence on the mechanical properties of the pre-treated Vectran fiber.
The plasma treatment could improved the deposition of the coating layer, but the surface roughness caused by plasma treatment
also affected the surface conductivity. It was found that the surface resistivity could reach very low value of 1.66×10−3 Ω·cm after sputtering deposition for 30 min. 相似文献
20.
Yibing Cai Xiaolin Xu Chuntao Gao Li Wang Qufu Wei Lei Song Yuan Hu Hui Qiao Yong Zhao Qi Chen Hao Fong 《Fibers and Polymers》2012,13(7):837-845
The ultrafine composite fibers consisting of lauric acid (LA) and polyamide 6 (PA6) as form-stable phase change materials (PCMs), were prepared successfully by electrospinning. The effect of carbon nanotubes (CNTs) on the structural morphology, phase change behaviors, thermal stability, flammability and thermal conductivity properties of electrospun LA/PA6 composite fibers was investigated by field-emission scanning electron microscopy (FE-SEM), differential scanning calorimetry (DSC), thermogravimetric analyses (TGA), microscale combustion calorimeter (MCC) and melting/freezing times measurements, respectively. SEM observations indicated that the LA/PA6 and LA/PA6/CNTs composite fibers possessed flat and ribbon-shaped morphologies, but the neat PA6 fibers had cylindrical shape with smooth surface; and the average fiber diameters for LA/PA6 composite fibers decreased generally with the addition of CNTs. DSC measurements indicated that the heat enthalpies of the composite fibers were lower that that of neat LA powders, while the amounts of CNTs had no appreciable effect on the phase change temperatures and heat enthalpies of the composite fibers. TGA results showed that the addition of CNTs increased the onset thermal degradation temperature, maximum weight loss temperature and charred residue at 700 °C of the composite fibers, attributed to the improved thermal stability properties. It could be found from MCC tests that there were two-step combustion processes for composite fibers, and corresponded respectively to combustion of LA and polymer chains (PA6) in composite fibers. The addition of CNTs reduced the peak of heat release rate (PHRR) of electrospun composite fibers, contributing to the decreased flammability properties. The improved thermal conductivity performances of LA/PA6/CNTs composite fibers was also confirmed by comparing the melting/freezing times of LA/PA6 composite fibers with that of neat LA powders. The results from the SEM observation showed that the composite fibers had no appreciable variations in shape and diameter after heating/cooling processes. 相似文献