Tunable functional properties on polyester fabric using simultaneous green reduction of graphene oxide and silver nitrate

Here, a novel method is introduced to create tunable properties on the polyester fabric through diverse chemical modifications. The polyester fabric was primarily modified with NaOH or ethylenediamine to enhance the surface activity. This will produce diverse chemical groups on the polyester fabric surface including carboxylate, hydroxyl and amine groups. The fabric was treated with grahene oxide through exhaustion method. The silver nitrate was then added and simultaneously reduced with grapheme oxide using ascorbic acid and ammonia to produce reduced graphen oxide/silver nanocomposites (rGO/Ag) on the fabric surface. The synthesized nanocomposites were characterized by TEM and Raman spectra. The presence and uniform distribution of the nanocomposites on the fabric surface was also confirmed by SEM images and EDX patterns. The electrical resistivity was varied on the raw and modified polyester fabric due to the diverse formation of the graphene nanosheets network on the fabric surface. More Ag particles were formed on the surface of the alkali hydrolyzed polyester whereas more graphene nanosheets deposited on the aminolyzed polyester fabric. Also the hydrolyzed polyester fabric exhibited higher antibacterial properties with the lowest silver nitrate in the processing solution. The aminolyzed fabric showed a lower electrical resistance than the hydrolyzed and raw fabrics with the same amount of GO in the procedure bath. The aminolyzed polyester fabric indicated higher affinity towards GO produced higher antibacterial properties before reduction and without silver nitrate however lower electrical resistance obtained after reduction comparing with other samples.     

Preparation of electroconductive,magnetic, antibacterial,and ultraviolet-blocking cotton fabric using reduced graphene oxide nanosheets and magnetite nanoparticles

The main goal of present study was the fabrication of cotton fabric with special functions, including electrical conductivity, magnetic, antibacterial, and ultraviolet (UV) blocking. In this regard, the cotton fabric was primarily coated with graphene oxide and then reduction of graphene oxide and synthesis of magnetite nanoparticles accomplished in one step. The alkaline hydrolysis of magnetite precursors and reduction of graphene oxide was simultaneously performed using sodium hydroxide to produce reduced graphene oxide/Fe₃O₄ nanocomposite on the fabric surface. The prepared cotton fabrics were characterized with field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The treated fabrics with reduced graphene oxide/Fe₃O₄ nanocomposite displayed a low electrical resistivity i.e. 80 kΩ/sq. Furthermore, the coated fabrics showed reasonable magnetic properties due to the presence of magnetite nanoparticles on the surface of cotton fabrics. Moreover, this process imparted proper antibacterial properties and UV blocking activity to cotton samples.     

Surface modification of polyester fibers by thermal reduction with silver carbamate complexes

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.     

Multifunctional modification of wool fabric using graphene/TiO<Subscript>2</Subscript> nanocomposite

In this study, a new finishing technique is introduced through treatment of wool fabric with graphene/TiO₂ nanocomposite. Graphene oxide/titanium dioxide nanocomposite first applied on the wool fabric by hydrolysis of titanium isopropoxide in graphene oxide suspension and then this coating chemically converted by sodium hydrosulfite to graphene/TiO₂ nanocomposite. The homogenous distribution of the graphene/TiO₂ nanocomposite on the fiber surface was confirmed by field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDS) and X-ray mapping. X-ray diffraction patterns proved the presence of titanium dioxide nanoparticles with a crystal size of 127 Å on the treated wool fabric. Also, the defect analysis based on X-ray photoelectron spectroscopy (XPS) established the composition of the nanocomposite. Other characteristics of treated fabrics such as antibacterial activity, photo-catalytic self-cleaning, electrical resistivity, ultraviolet (UV) blocking activity and cytotoxicity were also assessed. The treated wool fabrics possess significant antibacterial activity and photo-catalytic self-cleaning property by degradation of methylene blue under sunlight irradiation. Moreover, this process has no negative effect on cytotoxicity of the treated fabric even reduces electrical resistivity and improves UV blocking activity.     

Characteristics of Electrical Heating Elements Coated with Graphene Nanocomposite on Polyester Fabric: Effect of Different Graphene Contents and Annealing Temperatures

This paper reports the fabrication of electrical heating elements based on the graphene/waterborne polyurethane (WPU) composite coated on polyester fabric with toughness like that of artificial leather. Samples were prepared with 0, 4, 8, and 16 wt% of graphene by using the knife edge method, and then, the samples were annealed from 100 oC to 160 °C. The graphene content had a large effect on the electrical and electrical heating properties. The surface resistivity was decreased by approximately 6 orders of magnitude with an increase from 0 wt% to 16 wt% graphene/WPU composite fabric. The electric heating properties were also improved, as indicated by the percolation threshold. Samples with various graphene contents were annealed, and it was found that the electrical and electrical heating properties were improved, and the most enhanced properties were obtained when the samples were annealed at 120 °C. The initial modulus and tensile strength were increased in comparison with those of 0 wt% and 16 wt% graphene/WPU composite coated on fabrics, but the elongation at break value was slightly decreased with an increasing graphene content. When the samples were annealed, initial modulus and tensile strength of samples were improved at 120 °C and 140 °C, and they were slightly decreased at 160 °C. However, the elongation at break showed an opposite tendency to the tensile strength. With the increase in content of graphene and annealing at 120 °C and 140 °C, the samples were more stiff and tough, and at 160 °C, the samples were softer. Therefore, graphene/WPU composite coated on polyester fabric by use of the annealing process may have applications in electrical heating elements due to its excellent heating performance and toughness like that of artificial leather.     

Microstructure and properties of Ni-Fe3O4 composite plated polyester fabric

In this study, electroless Ni-Fe₃O₄ composite plating on polyester fabric modified with 3-aminopropyltrimethoxysilane (APTMS) was investigated under ultrasonic irradiation. Effects of deposit weight on microstructure and properties of Ni-Fe₃O₄ composite coating were studied. Surface morphology, chemical composition and state, crystal structure of the electroless Ni-Fe₃O₄ composite plated polyester fabric were characterized by SEM, EDX, XPS and XRD. Magnetic properties, electrical resistivity and electromagnetic interference (EMI) shielding effectiveness (SE) of Ni-Fe₃O₄ plated polyester fabric were also evaluated. The presence of co-deposition of Fe₃O₄ in Ni coating on the polyester fabric is demonstrated by an XPS analysis. At a higher deposit weight, there is an increase in particle size and saturation magnetization, and a decrease in electrical resistivity with respect to the rise of deposit weight, respectively. As the Ni-Fe₃O₄ weight on the treated fabric is 32.90 g/m², the EMI SE of the Ni-Fe₃O₄ plated polyester fabric arrives 15–20 dB at frequencies that range from 8 to 18 GHz. The results indicate the Ni-Fe₃O₄ plated polyester fabrics are used as super-paramagnetic, conductive and EMI shielding materials.     

Evaluation of Laundering Durability of Electro-conductive Textile Dip-coated on Para Aramid Knit with Graphene/Waterborne Polyurethane Composite

This study aims to fabricate an electro-conductive textile dip-coated with graphene/waterborne polyurethane (WPU) composite, and an evaluation of the laundering durability of this composite was conducted in order to confirm the application of the protective clothing. Samples were coated five times on the para-aramid knit with the graphene/WPU composite by the dip-coating method, and then hot-pressed processes were applied with various temperatures. The samples were washed 5, 10, 15, and 20 times, and then, morphology, surface resistance, and surface temperature were measured. After five laundering cycles, control and hot-pressed samples maintained surface resistivity from 10 kΩ/sq to 100 kΩ/sq. The surface resistivity of the control sample, however, was gradually increased up to 20 laundering cycles. The sample that was hot-pressed at 120 °C showed the lowest value of about 15 kΩ/sq with almost no variation from zero laundering cycles to 20, thus, it is the most stable sample up to 20 laundering cycles. When applied voltage at 50V, the surface temperature of the nonlaundering samples was presented as over 40.0 °C. In the case of the control sample, there was almost no electrical heating performance remaining after the fifth laundering test, but the hot-pressed samples maintained 40.0 °C or more at 50 V after the 10th laundering test. The sample that was hot-pressed at 120 °C in particular could maintain electrical heating performance at about an 80 % level up to the 10th laundering cycle. Therefore, the sample that was hot-pressed at 120 °C was the most stable in terms of electrical properties after 20 laundering cycles, and its electrical heating performance could be maintained even after 10 laundering cycles. It is expected that this process can be applied and used to make functional clothes for apparel and other applications.     

Screen printed silver patterns on functionalised aramid fabric

In this work, a simple and low cost method based on screen printing is presented to synthesize a conductive silver pattern on aramid fabric. The aramid fiber was treated with (3-mercaptopropyl)-trimethoxysilane to introduce a tail mercapto group promoting the ordered binding of silver nanoparticles. SEM and AFM images indicated a uniform distribution of silver nanoparticles on fiber surface. FTIR and XRD patterns confirmed the silver layer on the fibers. Furthermore, the electrical property of conductive fiber was characterized by conductive AFM and a digital multimeter, the surface resistance of conductive fabric was as low as 0.20 Ω/cm. And single fiber tensile test indicated that the mild treating process has no significant influence on the mechanical properties of the fiber.     

Electrical properties of graphene/waterborne polyurethane composite films

Graphene is classified as a carbon-based material. Structurally, graphene is made up of carbon-based two-dimensional atomic crystals and a one atom thick planar sheet of sp²-bonded carbon atoms. This sort of arrangement in graphene makes it a unique material with exceptional mechanical, physicochemical, thermal, electrical, optical, and biomedical properties. Methods for graphene-based fabric production mainly use graphene-based materials such as graphene (G), graphene oxide (GO), and reduced graphene oxide (rGO) coated on fabric or yarn. Waterborne polyurethane (WPU) is one of the most rapidly developing and active branches of polyurethane chemistry. More and more attention is being paid to graphene-coated fabrics owing to their low temperature flexibility, the presence of zero or very few VOCs (volatile organic compounds), water resistance, pH stability, superior solvent resistance, excellent weathering resistance, and desirable chemical and mechanical properties. It is used as a coating agent or adhesive for fibers, textiles, and leather. Also, graphene-containing materials have been used to enhance the properties of WPU. In this study, graphene/WPU composite solution and film was prepared to conduct basic research for developing electrical heating textiles which is not harmful to the human body, flexible and excellent in electrical properties. Graphene/WPU composite solutions were prepared with a graphene content of 0, 2, 4, 8, and 16 wt%, and graphene/WPU film was prepared with solution casting method. The graphene contents were analyzed for their surface morphology, electrical properties, and electrical heating properties.     

Surface characterization of sputter silver-coated polyester fiber

The present study concerns modification of surface of polyester fiber by magnetron sputtering using a silver (Ag) target. A detailed characterization of the silver-coated polyester fiber was investigated by scanning electron microscopy (SEM), X-ray diffraction technique (XRD) and X-ray photoelectron spectroscopy (XPS). The results revealed the remarkable changes in the surface morphology and microstructure of silver film on polyester fiber after sputtering for 10 and 30 min respectively. The SEM results showed that the silver particles were uniformly and densely deposited on the surface of polyester fiber. The XRD pattern of silver coated fabric showed that silver film is polycrystalline structure and dominated by the very strong (220) peak. Depth profiling results of silver coated fabric by XPS indicated that mainly metallic silver is existed throughout the whole depth region.     

Layer by layer assembly of nanosilver for high performance cotton fabrics

High performance cellulosic fabrics are of increasing attention as a wearable fabric with special functions. The current report deals with preparation of multifunctional cotton fabrics by using simple and facile layer by layer technique. Firstly, silver nitrate was reacted with carboxymethyl cellulose to prepare Ag nanoparticles-carboxymethyl cellulose composite. Multi-layers of the so-obtained composite were applied on the cotton fabrics using pad-dry-cure method. Ag nanoparticles were deposited with mean size of 18.2 nm onto cotton fabrics which served as a cross linker between carboxymethyl cellulose macromolecules and cotton macromolecular blocks. Application of composite multilayers brought new properties for the finished cloths such like coloration, ultraviolet resistance, electrical resistance and biocidal action. The ultraviolet transmission radiation was significantly reduced to 7-10 % after applying ten composite layers. Valuable antibacterial textiles which are required in different medical purposes could be successfully produced, as excellent antibacterial activities were achieved by using the reported method. The developed process can be easily adapted to the existing textile machinery, making it industrially viable to produce fabric’s versatility.     

Multifunctional colored polyester fabric treated with dopamine hydrochloride at room temperature: higher tensile,hydrophilicity and anti-bacterial properties along with aminolysis

In this work, dopamine hydrochloride, an environmental friendly compound, was applied on polyester fabric through conventional simple impregnation method in alkaline solution (pH=8.5) at room temperature. In situ spontaneous oxidative polymerization of dopamine form polydopamine (PDA) along with aminolysis of polyester fabric surface. Also, a range of colored polyester fabric were successfully achieved by formation of polydopamine adhesive coating layer at different concentration of dopamine hydrochloride (0.001-4 g/l). Fourier transform infrared spectroscopy and field emission scanning electron microscopy showed deposition of polydopmaine on the polyester fabric surface. The modified colored polyester fabric showed reasonable durability against washing, rubbing and light. The treated polyester fabric with 2 g/l dopamine hydrochloride as optimum concentration indicated not only lower spreading time for water droplet and electrical resistance with higher tensile strength but also very good bactericidal activity against Staphylococcus aureus and Escherichia coli.     

Electrical Resistivity of Plasma Treated Viscose and Cotton Fabrics with Incorporated Metal Ions

Cellulose fabrics (viscose and cotton) were treated with atmospheric pressure dielectric barrier discharge (DBD) in air. After DBD treatment, samples were characterized and volume electrical resistance was measured under different relative humidity conditions (φ=40-55 %). Results have shown that DBD treatment increases wettability and polar surface functional groups content, which consequently causes a decrease of volume electrical resistivity of cellulose fabrics in measured relative humidity range (φ=40-55 %). Metal ions (silver, copper, and zinc) were incorporated in untreated and plasma treated samples through sorption from aqueous solutions and incorporation of metal ions into plasma treated cellulose samples decreased electrical resistivity even further. Resistivity of cotton and viscose fabrics with incorporated metal ions followed the order Zn²⁺ > Cu²⁺ > Ag⁺. The most pronounced decrease, for entire order of a magnitude, was obtained by modification of cotton fabric with DBD and silver ions, where value of resistivity dropped from GΩ to a several dozens of MΩ.     

Polyester metallisation with electroless silver plating process

In this paper, electroless silver plating process for polyester was reported. The electroless silver plating is basically divided into four stages including pre-cleaning, sensitisation, electroless silver deposition and post-treatment. As the electroless silver plating stage is the key stage in affecting the brilliant appearance and various functional properties such as conductivity and ultra-violet protection, we will study the effect of process variables, i.e. amount of silver nitrate (AgNO₃), concentration of ammonium hydroxide (NH₄OH), concentration of sodium hydroxide (NaOH) and process temperature, using increased amount of silver in fabric surface as an indicator, for optimising the electroless silver plating process for possible industrial application. Experimental results revealed that amount of silver nitrate (AgNO₃)=1.77×10^?3 mole; concentration of ammonium hydroxide (NH₄OH)=6.25 %; concentration of sodium hydroxide (NaOH)=0.008 g/ml and process temperature=25 °C can give the best electroless silver plating for polyester fabric. The surface characteristics of the electroless silver-plated polyester fabric were evaluated by scanning electron microscope, X-ray photoelectron spectroscopy and X-ray diffraction analysis. Meanwhile, the performance properties of the electroless silver-plated polyester fabric were measured by CIE L*, a* and b* values, conductivity as well as ultraviolet protection. The experimental results would be discussed thoroughly in this paper.     

Electrical conductivity and chromic behavior of poly (3-methylthiophene) — coated polyester fabrics

Electrically conductive substrates with chromic behavior are prepared using conductive polymer coating of the substrate. Poly (3-methylthiophene) (P3MT) — coated polyester fabric with specific electrical and chromic properties, for instance electrochromic and piezochromic behavior, was successfully obtained by chemical polymerization with the help of continuous and speed stirring technique. The effect of polymerization time, temperature and oxidant concentration on conductivity of the P3MT-coated fabric was studied. The presence of P3MT particles on the surface of the coated substrate was confirmed by scanning electron microscopy (SEM), fourier transform infrared (FTIR) and UV-Vis spectroscopy, electrical surface resistivity, pressure and applied voltage dependence visible reflectance spectrophotometer measurements, and X-ray diffraction (XRD) analysis. The blue shift of c95 nm in wavelength of maximum absorption observed in the reflectance spectra of coated polyester fabric. Under high pressure, the P3MT-coated polyester fabric demonstrated piezochromism. The coated substrate also showed electrochromic behavior under an electrical applied voltage of 12 V.     

Preparation and properties of polypropylene nanocomposites reinforced with exfoliated graphene

We have prepared a series of polypropylene/exfoliated graphene (PP/EG) nanocomposite films via efficient meltcompounding and compression, and investigated their morphology, structures, thermal transition behavior, thermal stability, electrical and mechanical properties as a function of EG content. For the purpose, EG, which is composed of disordered graphene platelets as reinforcing nanoscale fillers, is prepared by the oxidation/exfoliation process of natural graphite flakes. SEM images and X-ray diffraction data confirm that the graphene platelets of EG are well dispersed in PP matrix for the nanocomposites with EG contents less than 1.0 wt%. It is found that thermo-oxidative degradation of PP/EG nanocomposites is noticeably retarded with the increasing of EG content. Electrical resistivity of the nanocomposite films was dramatically changed from ∼10¹⁶ to ∼10⁶ Ω·cm by forming electrical percolation threshold at an certain EG content between 1 and 3 wt%. Tensile drawing experiments demonstrate that yielding strength and initial modulus of PP/EG nanocomposite films are highly improved with the increment of EG content.     

Investigation of mechanical properties of developed antimicrobial PPsuture/Ag nanocomposite

In order to prevent surgical complications due to microbial infections, we have developed polypropylene suture grafted with silver nanoparticles (PPsuture/Ag nanocomposite) by a simple immersion procedure. Physical and mechanical properties of developed suture are investigated. Suture surface characteristics are examined by scanning electron microscopy (SEM) imaging and atomic force microscopy (AFM). Silver content on suture surface was determined by Inductively coupled plasma atomic emission spectroscopy (ICP-AES). The mechanical properties of developed antibacterial PP suture/Ag were studied. We note that proposed silver coating method has not affected mechanical performances of suture. Antimicrobial performances of PP suture/Ag nanocomposites against S. aureus and E. coli colonies were also investigated.     

Antibacterial effect of carbon nanofibers containing Ag nanoparticles

Silver nanoparticles imbedded in polyacrylonitrile (PAN) nanofibers and converted into carbon nanofibers by calcination was obtained in a simple three-step process. The first step involves conversion of silver ions to metallic silver nanoparticles, through reduction of silver nitrate with dilute solution of PAN. The second step involves electrospinning of viscous PAN solution containing silver nanoparticles, thus obtaining PAN nanofibers containing silver nanoparticles. The third step was converting PAN/Ag composites into carbon nanofibers containing silver nanoparticles. Scanning electron microscopy (SEM) revealed that the diameter of the nanofibers ranged between 200 and 800 nm. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) showed silver nanoparticles dispersed on the surface of the carbon nanofibers. The obtained fiber was fully characterized by measuring and comparing the FTIR spectra and thermogravimetric analysis (TGA) diagrams of PAN nanofiber with and without imbedded silver nanoparticles, in order to show the effect of silver nanoparticles on the electrospun fiber properties. The obtained carbon/Ag composites were tested as gram-class-independent antibacterial agent. The electrosorption of different salt solutions with the fabricated carbon/Ag composite film electrodes was studied.     

Application of silver nanoparticles to cotton fabric as an antibacterial textile finish

A novel nano-silver colloidal solution was prepared in one step by mixing AgNO₃ aqueous solution and an amino-terminated hyperbranched polymer (HBP-NH₂) aqueous solution under vigorous stirring at room temperature. All results of Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM) and UV/Visible Absorption Spectrophotometry indicated that silver nanoparticles had been formed in colloidal solution. Cotton fabric was treated with nano-silver colloid by an impregnation method to provide the cotton fabric with antibacterial properties. The whiteness, silver content, antibacterial activity and washing durability of the silver-treated fabrics were determined. The results indicated that the silver-treated cotton fabric showed 99.01 % bacterial reduction of Staphylococcus aureus and 99.26 % bacterial reduction of Escherichia coli while the silver content on cotton was about 88 mg/kg. The antimicrobial activity of the silver-treated cotton fabric was maintained at over 98.77 % reduction level even after being exposed to 20 consecutive home laundering conditions. In addition, the results of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) confirmed that silver nanoparticles have been fixed and well dispersed on cotton fabrics’ surface and the major state of the silver presented on the surface was Ag⁰.     

Synthesis of silver nanoparticles with sericin and functional finishing to cotton fabrics

This research presents a novel strategy to fabricate multi-functional cotton textiles. In this study, silver nanoparticles-sericin (Ag NPS-sericin) hybrid colloid has been prepared using sericin as reducing agent and dispersing agent. Cotton fabrics was oxidized selectively with sodium periodate (NaIO₄) to generate oxidized cotton fabrics, and which has then been finished using Ag NPS-sericin hybrid colloid prepared to obtain multi-functional cotton textiles. The finished cotton fabric not only possessed excellent antibacterial activity, but also it was modified functionally by sericin protein, which endowed antibacterial cotton fabrics relatively smooth surface and good wear ability. Fourier transform infrared spectrogram confirmed that sericin protein was grafted onto cellulose fibers. Ag NPs were characterized by UV-Vis spectroscopy, transmission electron microscope (TEM) and X-ray powder diffraction (XRD). The results of SEM, X-ray photoelectron spectroscopy (XPS) and EDS confirmed that silver nanoparticles and sericin been loaded successfully on the surface of cotton fabrics. The antibacterial experiments showed bacterial reduction rates of S.aureus and E.coli were able to reach above 99 %. After washing 20 times, it showed still good antibacterial activity at over 95 % against S.aureus and E.coli.