Reduction of 4-nitrophenol to 4-aminophenol over sonoimmobilized silver/reduced graphene oxide nanocomposites on polyester fabric

The current paper is aimed to compare different arrangement of Ag nanoparticles within silver/reduced graphene oxide (Ag/rGO) nanocomposites on the polyester fabric. rGO sheets cannot be dispersed in the water for long time however, thin layer surfactant-free Ag/rGO nanocomposites were immobilized on the surface of polyester. This leads to attain the preserved array of nanocomposites for a long time. TEM, FESEM/EDX, XRD, XPS, cyclic voltammetry, catalytic activity and electrical resistivity were used to characterize Ag/rGO nanocomposites coated polyester fabric. Interestingly, sonoimmobilization of Ag/GO produced an even coating layer of nanocomposites on the polyester fabric. The prepared fabric can be used as a high active and stable nanocatalyst for reduction of 4-nitrophenol (4-NP) in water at room temperature. The created flexible and light fabric showed low electrical resistance and high catalytic activity, wherein sonoimmobilization of Ag/rGO treated samples indicated highest catalytic activity as 4-NP solution completely reduced to 4- AP with assistance of 2×4 cm2 treated polyester after 25 min. On the other hand, introducing sonoprepared silver nanoparticles among graphene nanosheets led to significant lowering of electrical resistivity from 43 kΩ/square in mechanical stirring methodto 2 kΩ/square using ultrasound.     

Impregnation of zinc oxide mediated chitosan nano-composites on polyester fabric for performance characteristics

Present study dealt with the fabrication of chitosan/zinc oxide nano-composites (CZNCs) using a facile preparation method. The structural features of nano-composites were investigated by using advanced analytical techniques. The developed nano-composites exhibited hexagonal structural pattern with an average particle size of about 51 nm. The developed CZNCs were dispersed in 2-propanol and applied on polyester by using the pad-dry-cure method. The treated fabric specimens were characterized for surface, functional and textile properties including antibacterial activity and (ultra violet) UV- blocking. The nano-composite treated polyester fabric exhibited durable antibacterial, UV- blocking and textile properties with fair whiteness index.     

Photo-thermal conversion and thermal insulation properties of ZrC coated polyester fabric

Zirconium carbide (ZrC) films are deposited onto polyester fabric through magnetron sputtering. The deposited films are then examined by using field scanning electron microscopy and energy dispersive X-ray spectroscopy. The photothermal conversion property, film thickness, infrared reflectance and transmittance, and thermal conductivity are also evaluated. The results show that the highest far-infrared emissivity of polyester fabric deposited with ZrC is 0.9379. The ZrC deposited samples showed a small increase in thermal conductivity with a difference of 0.0611W/m·K, and a higher photothermal conversion efficiency with a temperature increase of 27.5 °C in 100 s, when the thickness of the ZrC film is 1920 nm. These therefore indicate that coating fabrics with ZrC through magnetron sputtering is an environmentally friendly means to produce textiles with photo-thermal conversion and heat insulation properties.     

Plasma-assisted surface modification of polyester fabric for developing halochromic properties

In the field of textiles, introducing pH-sensitive dyes onto fibrous materials is a promising approach for the development of flexible sensor. In this study, poly(ethylene terephthalate) (PET) textile surface with halochromic properties was fabricated by plasma-assisted sol-gel coating, followed by immobilization of two different azo pH-indicator dyes; namely Brilliant yellow and Congo red by conventional printing technique of fabrics. 3-aminopropyltriethoxysilane (APTES) was used as a coupling agent for attaching the pH-sensitive dyes through its terminal amines. The surface immobilization of APTES on PET fabric was conducted by the pad-dry-cure method. Moreover, the influence of oxygen plasma pre-treatment and the method of post-treatment either by oxygen plasma or by thermal treatment on the stability of sol-gel based matrix was investigated. The morphology and chemistry of 3-aminopropyltriethoxysilane coated PET surfaces were examined by using surface sensitive methods including electrokinetic and time-dependent contact angle measurements as well as X-ray photoelectron spectroscopy (XPS). In addition, fastness tests of the printed fabrics and color strength were carried out to assess the effectiveness of the fabric surface modification. Results indicate that sol-gel matrix exhibited a more stability by thermal post-treatment at 150 C for 5 min. Also, the results revealed that the printed fabrics with halochromic properties demonstrated sufficient stability against leaching by washing. The current work opens up a novel opportunity to develop flexible sensors based on fibrous materials, which have the potential to be employed in variable industrial applications.     

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.     

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.     

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.     

Optimization of electroless nickel plating on polyester fabric

Electrical conductivity is an important property of electroless nickel plated fabric. The optimized electroless nickel plating method can provide useful information for textile industries to obtain optimum surface resistance and stable plating. In this study, a screening experiment with factorial design and response surface method (RSM) with central composite design (CCD) was used to optimize the electroless nickel plating on polyester fabric. A two-level full factorial design (FFD) was used to determine the effects of five factors, i.e. the concentrations of nickel sulfate, sodium hypophosphite and sodium citrate, pH and temperature of the plating solution on surface resistance of the electroless nickel plated fabric. It is found that the nickel sulfate concentration and temperature of the plating solution are the most significant variables affecting the surface resistance of electroless nickel plated fabric. The optimum operating condition is finally obtained by using a desirability function. The test for reliability for predicting response surface equations shows that these equations give an excellent fitting to the observed values. In addition, the deposit composition, surface morphology, crystal structure and electromagnetic interference (EMI) shielding effectiveness (SE) were studied. The EMI SE of the nickel plated polyester fabric obtained under the optimal condition is about 60 dB at the frequency ranging from 2 to 18 GHz.     

The effect of fabric balance and fabric cover on surface roughness of polyester fabrics

The effects of fabric balance and fabric cover on surface roughness values of textured polyester woven fabrics with different constructional parameters were investigated. The warp yarn properties (type, count and warp density) were kept constant while the effect of variation in weft yarn density and weave pattern were studied. Measurements were conducted on pre-treated white fabric samples and the results assessed in relation to their constructional properties. A general overview of the results showed that surface roughness values of polyester fabrics affected by fabric balance and fabric cover and the effects were related to fabric thickness, yarn densities, yarn crimp, positioning of yarns in fabric structure. A change in weave pattern from sateen to plain increased the fabric balance and fabric cover, but decreased the surface roughness. Similarly, an increase in weft density increased the fabric balance and fabric cover, but decreased surface roughness. In order to produce fabrics with smooth surface properties yarn density should be increased, yarn float lengths decreased, cover of fabrics increased and fabric balance improved.     

Antibacterial cotton fabric with enhanced durability prepared using L-cysteine and silver nanoparticles

L-cysteine (Cys) and silver nanoparticles (Ag NPs) were successfully linked onto the cotton fabric surfaces. The Cys molecules were covalently linked to the cotton fibers via esterification with the cellulose hydroxyl groups, and the Ag NPs tightly adhered to the fiber surface via coordination bonds with the Cys thiol groups. As a result, the Ag NPs coating on the cotton fabric showed an excellent antibacterial function with an outstanding laundering durability. The bacterial reduction rates (BR) efficiency reached 100 % for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). After 50 consecutive laundering cycles, the bacterial reduction rates (BR) against E. coli and S. aureus were maintained over 97 %. It has potential applications in a wide variety of fields such as sportswear, socks, and medical textile.     

Warp and weft directional tensile properties of multistitched woven fabric E-glass/polyester nano composites

The aim of this study was to understand the warp and weft directional tensile properties of the developed two dimensional (2D) multistitched multilayer E-glass/polyester woven nano composites. It was found that the warp and weft directional specific tensile strength and modulus of unstitched structure were higher than those of the machine stitched and machine stitched/nano structures due to stitching caused filament breakages. When the nano silica material in the unstitched E-glass/polyester composite structure increased, the warp and weft directional specific tensile strength and the modulus of the unstitched/nano structures increased. The failure of warp and weft directional 2D unstitched and unstitched/nano woven E-glass/polyester composite structures had a complete delamination in their cross-sections. But, the failure of warp and weft directional 2D stitched and stitched/nano woven E-glass/polyester composite structures had a local delamination in their cross-sections and the failure was confined at a narrow area. The warp and weft directional specific damaged areas of unstitched structure were higher than those of the stitched and stitched/nano structures. Also, the warp and weft directional specific damaged areas of machine stitched structure were slightly higher than those of the machine stitched/nano structure. It could be concluded that the addition of nano silica to the stitched structures improved to their damage resistance.     

Durable multifunctional properties on acrylic fabric using nano TiO2 and polysiloxane

Producing fabric with multifunctional properties has been recently a center of research and utilizing nanoparticles is an efficient approach to gain this purpose. Here, nano TiO₂ photo catalyst and polysiloxane softener were utilized as stabilizer on the acrylic fabric to obtain soft handle, hydrophilic, and self-cleaning features on the fabric. The effect of various concentrations of nano TiO₂ and polysiloxane on the fabric handle, water droplet absorption time, and self-cleaning properties of the fabric has been mathematically modeled based on the response surface methodology (RSM). The optimized treatment conditions indicated that treated acrylic fabric with 2.19 % polysiloxane and 0.68 % nano TiO₂ produced the rigidity of 26.8 g.cm, water absorption time of 15.8 s and self-cleaning of ΔE _T *=18.1. Also increasing the concentration of polysiloxane enhanced both wettability and photoactive properties of nano TiO₂ treated acrylic fabrics. Further, the nano TiO₂/polysiloxane treated acrylic fabrics is significantly enable to absorb the light with wavelength lower than 400 nm and improve discoloration of C.I. Reactive Yellow 1.     

Effects of deposition parameters of electroless copper plating on polyester fabric

Properties of electroless copper-plated polyester fabric mainly depend on the plating bath constituents/conditions. The nickel serves to catalyze the copper deposition when hypophosphite is used as a reducing agent. In this study, the effects of deposition parameters including additive NiSO₄ concentration and pH on microstructure and properties of the electroless copper plating on polyester fabric using hypophosphite as a reducing agent were investigated. The results show that at a higher NiSO₄ concentration, the copper content present in the coating decreases whereas the nickel content increases slightly. On the other hand, the copper content present in the coating increases, whereas the nickel content and phosphorus decreases with respect to the rise of pH. The morphology of the copper deposits show that the particle size increase with respect to the rise of NiSO₄ concentration and pH. The XRD patterns indicate that the copper-plated polyester fabrics are crystalline. In addition, there is a decrease in the surface resistance and an increase in the electromagnetic interference (EMI) shielding effectiveness (SE) with respect to the rise of Ni²⁺ concentration and pH of the solution as a result of gaining a greater weight in the deposits. The results suggest that the copper-plated polyester fabrics have a great potential application as an EMI shielding material.     

Effect of various shapes of zinc oxide nanoparticles on cotton fabric for UV-blocking and anti-bacterial properties

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.     

Preparation and photocatalytic activity of bismuth tungstate coated polyester fabric

Bi₂WO₆ particles were prepared and then coated on the polyester fabric. Surface morphology, crystal structure, and chemical structure of the Bi₂WO₆ particle coated polyester fabric were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Photocatalytic activity was evaluated by the degradation of methylene blue (MB) under ultraviolet light irradiation. Influences of the different concentrations of Bi₂WO₆ on the deposit weight and the photocatalytic activity of the Bi₂WO₆ particle coated polyester fabric were investigated. In addition, UV protection of the Bi₂WO₆ particle coated polyester fabric was examined. The results show that Bi₂WO₆ particles are uniformly coated on the surface of the polyester fabric. The Bi₂WO₆ particles coated on the polyester fabric are irregular and are orthorhombic. In addition, the Bi₂WO₆ particle coated polyester fabric exhibits excellent photocatalytic activity and UV protection. The average degradation efficiency of MB in the presence of the Bi₂WO₆ particle on the polyester fabric coated with 10 g/l Bi₂WO₆ reaches 98.6 % after being illuminated for 7 h. Therefore, the Bi₂WO₆ particle coated polyester fabric shows excellent photocatalytic stability for dyes degradation.     

Effect of chelating agent in disperse dye dyeing on polyester fabric

In this study, mild acid based chelating agents (glycolic acid, gluconic acid, ethylenediaminetetraacetic acid, and citric acid) were used for the dyeing of polyester fabrics with metal sensitive disperse dye in closed dyeing process. The chelating and pH adjustment efficiencies were compared in disperse dyeing condition. In the comparative analysis with different chelating agents, glycolic acid showed a higher chelation efficiency and consequently showed higher dye bath exhaustion and color strength. Slight differences in the color fastness of the dyed samples obtained by employing four different chelating agents were observed.     

Mechanical and thermal properties of epoxy composites containing graphene oxide and liquid crystalline epoxy

The graphene oxide (GO) sheets are chemically grafted with γ-etheroxygentrimethoxysilane (KH560) and liquid crystalline epoxy (LCE) is synthesized from 4,4′-bis(2-hydroxyhexoxy)biphenyl (BP₂) and epichlorohydrin before being incorporated into epoxy matrix. Then we present a novel approach to the fabrication of advanced polymer composites from epoxy matrix by incorporation of two modifiers, which are grafted GO (g-GO) and LCE. The mechanical properties of epoxy composites are greatly improved by incorporating LCE/g-GO hybrid fillers. For instance, the addition of 3 wt% hybrid filler (2 wt% g-GO and 1 wt% LCE) into the epoxy matrix resulted in the increases in impact strength by 132.6 %, tensile strength by 27.6 % and flexural strength by 37.5 %. Moreover, LCE/g-GO hybrid fillers are effective to increase thermal decomposition temperature, glass transition temperature, and storage modulus by strong affinity between the fillers and epoxy matrix.     

Simultaneous synthesis of nano ZnO and surface modification of polyester fabric

In this study, synthesis of zinc oxide nanoparticles was carried out along with the hydrolysis of polyester fabric using sodium hydroxide to increase the surface activity and enhance the nanoparticles adsorption. The polyester fabrics were treated with zinc acetate and sodium hydroxide at different bath conditions, ultrasound and stirrer, resulting in formation of ZnO nanospheres and ZnO nanorods. The presence of zinc oxide with different shapes on the surface of the polyester fabrics was confirmed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Also, the X-ray diffraction patterns established the composition of wurtzite structure of zinc oxide. The self-cleaning property of treated polyester fabrics was evaluated through discoloring dye stain under sunlight irradiation. The antibacterial activities of the samples against two common pathogenic bacteria including Escherichia coli and Staphylococcus aureus were also assessed. The results indicated that the photocatalytic and antibacterial activities of the ultrasound treated polyester fabrics were superior compared to the stirrer treated samples.     

Surface treatments of jute fabric: The influence of surface characteristics on jute fabrics and mechanical properties of jute/polyester composites

In this study, jute fabrics were modified by alkali, micro-emulsion silicon (MS) and fluorocarbon based agents (FA) in order to enhance the interfacial adhesion between the polyester matrix and the jute fiber. X-ray photoelectron spectroscopy (XPS) and contact angle measurements were used to characterize fiber surfaces. The effects of various surface treatments on the mechanical and morphological of jute/polyester composites were also studied. All surface treatments were shown to improve the tensile, flexural strengths and interlaminar shear strengths of the composites. Moreover, the maximum improvement in the mechanical properties was obtained for the FA treated jute/polyester composites. SEM micrographs of the tensile fracture surface of jute/unsaturated polyester composites also exhibited improvement of interfacial and interlaminar shear strengths by the alkali, MS and FA treatments of jute fibers.     

Novel nanocomposites based on hydroxyethyl cellulose and graphene oxide

In the present study, nanocomposites films formed by hydroxyethyl cellulose (HEC) and graphene oxide (GO) were synthesized and characterized. Compared with pure hydroxyethyl cellulose film, the thermal stability and mechanical properties of the composite materials were significantly improved. When the graphene loading was only 1.0 wt%, the maximum weight loss temperature increased 11.14 °C. The tensile strength and Young’s modulus of HEC/GO nanocomposites films were increased by 30.28 and 75.63 % compared to the pure HEC films, with only 1.0 wt% GO. The X-ray diffraction and Fouriertransform infrared spectroscop showed that GO sheets were completely exfoliated in the HEC matrix and suggested the presence of the weak interaction between HEC and GO sheets because of large number of oxygen-containing hydrophilic functional groups on the surface and edge of GO sheets. Furthermore, the well-dispersed GO nanosheets in the films can be inferred from the SEM and Halpin-Tsai model analysis. On the other hand, the composite films showed improved barrier properties against oxygen. This simple process for preparation of HEC/GO films is attractive for potential development of high-performance films for packing applications.