Comparison of copolymer emulsions of fluorine and siloxane‐containing acrylates with core–shell structure for water‐repellent cotton fabrics coatings

This paper described the synthesis of copolymer emulsions of fluorine and siloxane‐containing acrylates for water‐repellent cotton fabrics coatings. Chemical composition, morphology structure, and properties of the latex copolymers were investigated by Fourier transform infrared (FTIR), dynamic light scattering (DLS), gel permeation chromatography (GPC), and transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Effects of water‐repellent functional monomers (R_f) on surface morphology, water contact angle, and water‐repellent properties of the coated fabric surface were also studied. The results indicated that R_f greatly influenced molecular mass distribution of the latex copolymers, the molecular aggregation states and orientation of R_f on the coated fabric surface, and water‐repellency of coated cotton fabrics. Copyright © 2014 John Wiley & Sons, Ltd.     

Using graphene/TiO2 nanocomposite as a new route for preparation of electroconductive,self-cleaning,antibacterial and antifungal cotton fabric without toxicity

A novel and efficient process is reported for fabrication of electroconductive, self-cleaning, antibacterial and antifungal cellulose textiles using a graphene/titanium dioxide nanocomposite. Cotton fabric was loaded with graphene oxide using a simple dipping coating method. The graphene oxide-coated cotton fabrics were then immersed in TiCl₃ aqueous solution as both a reducing agent and a precursor to yield a fabric coated with graphene/titanium dioxide nanocomposite. The crystal phase, morphology, microstructure and other physicochemical properties of the as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and UV-Vis reflectance spectroscopy. Electrical resistance, self-cleaning performance, antimicrobial activity and cytotoxicity of treated fabrics were also assessed. The electrical conductivity of the graphene/titanium dioxide nanocomposite-coated fabrics was improved significantly by the presence of graphene on the surface of cotton fabrics. The self-cleaning efficiency of the treated fabrics was tested by degradation of methylene blue in aqueous solution under UV and sunlight irradiations. The results indicated that the decomposition rates of methylene blue were improved by the addition of graphene to the TiO₂ treatment on fabrics. Moreover, the graphene/titanium dioxide nanocomposite-coated cotton samples had negligible toxicity and possessed excellent antimicrobial activity.     

Cotton fabrics treated with acylhydrazone-based polyviologen to create innovative multi-stimulus responsive textiles

Novel multi-stimuli responsive cotton fibers were developed via spray-coating with an acylhydrazone-based polyviologen (AHPV). Polyviologen was prepared by supramolecular condensation polymerization of bipyridinium dialdehyde with a hydroxyl-substituted aryldihydrazide in an acidified aqueous medium. Transparent AHPV/resin nanocomposite film was deposited onto the surface of cotton fabric by well-dispersion of AHPV as a chromogenic substance in a resin binding agent. Increasing the temperature of the AHPV-coated cotton fabric from room temperature to 85 °C reversibly triggered a change in color from pale yellow (437 nm) to green (607 nm), respectively. The transparent layer immobilized onto the white cotton surface transformed into green under ultraviolet source as demonstrated by CIE Lab parameters. The photochromic impacts were explored at various AHPV. In addition, the AHPV-coated cotton immediately displayed a vapochromic activity upon exposure to NH_3(g), and then recovered to pale yellow after removing the ammonia source away. The current AHPV-coated cotton fabric displayed a limit of detection (LOD) to NH_3(aq) in the range of 50–150 ppm. The spray-coated cotton fabrics demonstrated a reversible photochromism, thermochromism and vapochromism with high stability. The produced AHPV nanoparticles were also studied by transmission electron microscopy (TEM), demonstrating particle diameter of 74–92 nm. The mechanical and morphological properties of the spray-coated cotton fabrics were also explored. The surface morphology of AHPV-finished samples was examined by Fourier-transform infrared (FTIR) and scanning electron microscopy (SEM). No considerable defects were observed in permeability to air and bending length of AHPV-finished samples. Additionally, high colorfastness was monitored for the AHPV-finished cotton substrates. The cytotoxic activity of the AHPV-finished cotton was also examined. Mechanistic study accounting for the multichromic activity of acylhydrazone-based polyviologen is explored.     

Preparation, characterization, and antimicrobial property of cotton cellulose fabric grafted with poly (propylene imine) dendrimer

Two generations of poly (propylene imine) dendrimer with amino terminated groups (G2- and G5-PPI-NH₂) were grafted on cotton cellulose fabric using cross linking agents (citric or glutaric acids). Fourier transform infrared (FTIR) spectroscopy identified ester groups which were formed between hydroxyl groups of the cotton fabric and carboxylic groups of the cross linking agents. Also, attenuated total reflectance-FTIR (ATR-FTIR) analysis confirmed formation of amide groups between the carboxylic groups of the cross linking agents and the amino end groups of the dendrimers. Nitrogen content (N-content) analysis revealed the presence of the dendrimers on the cotton fabric even after 5 washing cycles. In order to study the dispersion of the PPI dendrimers on the surface of the cotton fabric, field emission scanning electron microscopy (FE-SEM) was performed. The particle size distribution of the G2- and G5-PPI-NH₂ aqueous solutions was also determined by dynamic light scattering (DLS) analysis. Antimicrobial activity of the PPI dendrimer aqueous solutions and the cotton cellulose fabric grafted with the dendrimers was evaluated both quantitatively and qualitatively against Gram-positive bacterium (Staphylococcus aureus), Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) and fungus (Candida albicans). The dendrimer grafted cotton cellulose fabric exhibited a 99 % reduction in bacterial counts against S. aureus, E. coli and C. albicans. The antimicrobial activities of the grafted cotton cellulose fabric with the PPI dendrimers were maintained even after 5 washing cycles.     

Synthesis of gold nanoparticles using herbal Acorus calamus rhizome extract and coating on cotton fabric for antibacterial and UV blocking applications

Gold nanoparticles (AuNPs) have been synthesized by greener method using chloroauric acid as precursor and extract of Acorus calamus rhizome as reducing agent. Formation of AuNP was confirmed by the presence of Surface Plasmon Resonance (SPR) peak in UV–Visible spectral analysis. XRD and FT-IR spectral analyses were performed for characterization. SEM images show spherical morphology and HR-TEM images reveal nanosize of AuNPs. The AuNPs were then coated on cotton fabric by pad-dry-cure method and characterized by SEM with EDAX technique. The results reveal the deposition of AuNPs on the surface of cotton fabric. Uncoated cotton, neat extract coated cotton and extract containing AuNPs coated cotton fabrics were then tested for antibacterial activity against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli) bacterial strains by AATCC 100 test method. It showed that the extract containing AuNPs coated cotton fabric had higher antibacterial activity than other test samples against E. coli. UV-DRS analysis performed on extract containing AuNPs coated cotton fabric showed improved UV-blocking property than uncoated cotton fabric and neat extract coated cotton fabric.     

The antimicrobial activity of the cotton fabric grafted with an amino-terminated hyperbranched polymer

An amino-terminated hyperbranched polymer (HBP-NH₂) was grafted to cotton fabric by a reaction between the aldehyde groups of oxidized cotton fabric and the amino groups of the HBP-NH₂ to provide cotton fabric with durable antimicrobial properties. The antimicrobial activities of the HBP-NH₂ aqueous solutions and the HBP-NH₂ grafted cotton fabrics were evaluated quantitatively against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The results indicated that the HBP-NH₂ grafted cotton fabric showed 92% of bacterial reduction to S. aureus and 95% of bacterial reduction to E. coli, respectively. The antimicrobial activities of the HBP-NH₂ grafted cotton fabrics were maintained at over 91% reduction level even after being exposed to 20 consecutive home laundering conditions. Several influence factors, which may affect the amount of HBP-NH₂ grafted onto the cotton fabrics, were also discussed.     

Preparation of durable superhydrophobic surface by sol–gel method with water glass and citric acid

Durable superhydrophobic surface on cotton fabrics has been successfully prepared by sol–gel method. Cellulose fabric was first coated with silica sol prepared with water glass and citric acid as the acidic catalyst. The silica coated fabric was then padded with hydrolyzed hexadecyltrimethoxysilane afterwards obtaining low surface energy. Water contact angle and hydrostatic pressure were used to characterize superhydrophobicity and washing durability. Scanning electron microscopy was used to characterize the surface morphology changes after certain washing times. All results showed good durable hydrophobicity on cellulose fabrics. In addition, the influence of citric acid and sodium hypophosphite (NaH₂PO₂) on the durability of hydrophobicity was also investigated. The durability of treated cotton improved with the increase of concentration of citric acid in the presence of NaH₂PO₂. It could be concluded that citric acid acted as multi-functional heterogeneous grafting chemicals to improve washing durability of hydrophobicity by forming the ester bonds between cotton fabric and silica sol and improved the durability of hydrophobicity.     

Functionalization of cotton fabrics with rutile TiO<Subscript>2</Subscript> nanoparticles: Applications for superhydrophobic,UV-shielding and self-cleaning properties

The superhydrophobic cotton fabrics were prepared by combining the coating of titanium dioxide (TiO₂) with the subsequent dodecafluoroheptyl-propyl-trimethoxysilane (DFTMS) modification. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) measurements revealed that the nanosized TiO₂ sphere consisted of granular rutile. The TiO₂ layer coated on the cotton altered both the surface roughness for enhancing the hydrophobicity and UV-shielding property. The cotton fabric samples showed excellent water repellency with a water contact angle as high as 162°. The UV-shielding was characterized by UV-vis spectrophotometry, and the results indicated that the fabrics could dramatically reduce the UV radiation. The photocatalytic progress showed that organic stains were successfully degraded by exposure of the stained fabric to UV radiation. Such multifunctional cotton fabrics may have potentials for commercial applications.     

Polyhedral oligomeric silsesquioxane‐based fluoroether‐containing terpolymers: Synthesis,characterization and their water and oil repellency evaluation for cotton fabric

A series of polyhedral oligomeric silsesquioxane (POSS) based hybrid copolymers poly(POSS‐co‐methyl methacrylate ?co‐ 4‐vinylbenzyl fluoroether carboxylate) ( P(POSS‐MMA‐VBFC) ) were prepared via radical polymerization and characterized by nuclear magnetic resonance, fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, gel permeation chromatography, X‐ray powder diffraction, scanning electron microscopy and transmission electron microscopy. The thermal properties of these polymers (T_d > 250 °C) were improved by the introduction of POSS cage. The cotton fabrics coated with the polymers possessed excellent water and oil repellency. The water and salad oil contact angle could be achieved from 133° to 159° and from 127° to 141° respectively as the content of POSS in the polymer increased from 0 to 7.1 wt %. Moreover, the cotton fabric coated with the terpolymer was less flammable than the uncoated one. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Application of ZnO nanoparticles to enhance the antimicrobial activity and ultraviolet protective property of bamboo pulp fabric

Hyperbranched polymer HSDA was synthesized from methyl acrylate, tetraethylenepentamine, and dodecanoic acid by melt polycondensation. ZnO nanoparticle colloidal solution was prepared in one step by mixing Zn(NO₃)₂ and HSDA aqueous solution under hydrothermal condition. The results of transmission electron microscopy and ultraviolet–visible (UV–Vis) spectroscopy indicated that ZnO nanoparticles were formed in colloidal solution. Bamboo pulp fabric was treated with ZnO nanoparticle colloidal solution by an impregnation method to provide the bamboo pulp fabric with antibacterial and UV protective properties. The whiteness, antibacterial activity, UV protective property, and washing durability of the ZnO nanoparticle-treated fabrics were determined. The results indicated that the bamboo pulp fabric treated with ZnO nanoparticles showed good UV protective properties and its ultraviolet protection factor (UPF) can reach 90.38. The UPF value of treated fabric drops to 70.42 after washing for 20 times, but it retains good UV protective properties. The ZnO nanoparticle-treated fabric showed 99.91 % bacterial reduction of Staphylococcus aureus and 99.97 % bacterial reduction of Escherichia coli. The fabric retained over 98.93 % reduction level even after being exposed to 20 consecutive home-laundering conditions. In addition, the results of scanning electron microscopy and X-ray spectroscopy confirmed that ZnO nanoparticles were fixed and well dispersed on bamboo pulp fabric.     

In situ production of silver nanoparticle on cotton fabric and its antimicrobial evaluation

An ecological and viable approach for the in situ forming silver nanoparticles (AgNPs) on cotton fabrics has been used. Silver nanocoated fabric of brownish yellow color (AgNPs, plasmon color) was characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). SEM images revealed that the surface of the modified cotton was rougher than that of normal cotton. In addition, SEM images showed the presence of AgNPs on the surface of the treated fabric. Silver mapping and elemental analysis of the silver nanocoated cotton fabric using EDS confirmed the presence of AgNPs in a homogeneous distribution. Also, FTIR spectra of silver nanocoated sample showed more intense and broad peaks with a slight red shift if compared with those of blank sample indicating the binding of AgNPs with cellulose macromolecules. Different coating levels and the impact of repeated washings have been evaluated against different microbial strains by growth inhibition zone. The results of antimicrobial studies reveal that the presence of a low coating level of nanosilver is enough for producing an excellent and durable antimicrobial cotton fabrics.     

Effects of plasma treatments for improving extreme wettability behavior of cotton fabrics

A simple, environmentally benign and energy efficient process for fabricating single faced superhydrophilic/hydrophobic cotton fabrics by controlling surface texture and chemistry at the nano/microscale is reported here. Stable ultra-hydrophobic surfaces with advancing and receding water droplet contact angles in excess of 146° as well as extreme superhydrophilic surfaces are obtained. Hydrophobic water-repellent cotton fabrics were obtained following plasma treatment through diamond-like carbon (DLC) coating by plasma enhanced chemical vapour deposition. The influence of changing different precursor’s plasma pre-treatments such as H₂, Ar or O₂ on the properties of DLC coatings is also evaluated using atomic force microscopy, X-ray photoelectron spectroscopy, attenuated total reflection Fourier transform infrared spectroscopy, and analysed in terms of contact angle measurements. Because of the DLC coating, the coated fabric showed to endure its superhydrophobic character even after 12 months.     

Bactericidal Effect of Poly(Acrylamide/Itaconic Acid)–Silver Nanoparticles Synthesized by Gamma Irradiation Against Pseudomonas Aeruginosa

Antimicrobial activity of silver nanoparticles is gaining importance due its broad spectrum of targets in cell compared to conventional antimicrobial agents. In this context, silver nanoparticles were synthesized by gamma irradiation-induced reduction method of acrylamide and itaconic acid with irradiation dose up to 70 kGy. Silver nanoparticles were examined by Fourier-transform infrared, scanning electron microscopic images (SEM), and ultraviolet–visible spectrophotometer. The particle size was determined by X-ray diffraction, transmission electron microscopy (TEM), and dynamic light scattering. The antibacterial effect was studied by disk diffusion method against some bacterial pathogenic strains. Silver nanoparticles showed promising activity against Pseudomonas aeruginosa and slightly active against Escherichia coli, methicillin-resistant Staphylococcus aureus, and Klebsiella pneumonia. The bactericidal effect of silver nanoparticles was tested against P. aeruginosa. The killing rate of P. aeruginosa was found to be 90 % of viability at (100 μl/ml) of silver nanoparticles. Exposure of P. aeruginosa cells to silver nanoparticles caused fast loss of 260 nm absorbing materials and release of potassium ions. The TEM and SEM observation showed that silver nanoparticles may destroy the structure of bacterial cell membrane in order to enter the bacterial cell resulting in the leakage of the cytoplasmic component and the eventual death.     

Effects of TiO<Subscript>2</Subscript> on the hydrophilicity of сotton/polyester (50/50) blend fabric under UV irradiation

Alkaline TiO₂ nanoparticles treated cotton/polyester (50/50) blend fabric were prepared, and then exposed to UV irradiation. It was found that the addition of a small amount of TiO₂ nanoparticles to the coating solution improves the hydrophilicity and mechanical strength of the fabrics. The treated fabrics exhibited high water absorption as well as better hydrophilicity compared to the untreated sample. Compared to the surface of untreated blend fabric, scanning electron microscopy showed that the surface of the modified blend fabric becomes rough and covered by a layer of other materials. Furthermore, X-ray diffraction demonstrated the formation of crystalline material. In addition, thermograms showed that the modification process improved the thermostability of blend fabric.     

Decolourization of vat dyes on cotton fabric with infrared laser light

A method for the decolourization of coloured cotton fabric dyed with vat dyes, based on exposure to infrared laser light, has been tested. Pulsed CO₂ laser has been used for all experiments. To detect changes in colour shade, reflection data of original and dyed cotton irradiated at various fluency of infrared laser light were measured on a UV–VIS spectrophotometer, and then colour intensity was calculated for each vat dye. To observe changes in chemical composition and morphology of fiber surfaces, an analysis was performed by X-ray photoelectron spectroscopy and scanning electron microscopy due to thermal effects. Thermal stability of vat dyes and cotton fabric was determined with differential scanning calorimetry method to simulate the heating process during exposure of samples to the infrared laser irradiation.     

Thermal properties of cotton fabric modified with poly (propylene imine) dendrimers

For the first time, thermal stability and flame retardant properties of cotton fabrics modified with poly (propylene imine) dendrimer (PPI-dendrimer) using cross linking agents have been reported. The PPI-dendrimers can be considered as novel nitrogen flame retardant agents, because they contain a large number of nitrogen-containing groups (amine end groups), which may release nitrogen gas or ammonia. In this paper, the effect of the PPI-dendrimers on thermal behavior of cotton fabric is investigated through thermogravimetric analysis, differential scanning calorimetry, flammability (in vertical configuration) and limiting oxygen index tests. Indeed, both thermal stability and flame retarancy of the modified fabrics have significantly enhanced. Furthermore, field emission scanning electron microscopy micrographs have been studied in order to evaluate morphology of the cotton samples. Crystallinity and physical properties including crease recovery angle, breaking strength, whiteness index and hygroscopicity of the samples have been also assessed.     

In situ growth of MnO2 on pDA-templated cotton fabric for degradation of formaldehyde

Degradation of formaldehyde (HCHO) in interior decoration has been an urgent issue due to its toxicity nature and potential threats to human health. In this work, manganese dioxide nanoparticles (MnO₂ NPs) were in situ grown on the polydopamine (pDA)-templated cotton fabrics for environmentally friendly HCHO degradation applications. The morphology, elemental composition, and crystal structure of the cotton/pDA/MnO₂ were characterized by scanning electron microscopy–energy dispersive X-ray spectrum, Fourier transform infrared, X-ray diffractometer and X-ray photoelectron spectroscopy, respectively. The degradation of HCHO by the as-developed cotton/pDA/MnO₂ was measured in a self-made quartz reactor, and the stability of adsorption was evaluated by cyclic experiments. The results showed that the HCHO removal efficiency reached to 100% within 20 min after three cycles, suggesting that the as-prepared fabrics exhibited good stability for the degradation of HCHO. The development of MnO₂ NPs coated fabrics provides new strategies in degradation HCHO in interior decoration.

     

The comparison of differences in flammability and thermal degradation between cotton fabrics treated with phosphoramidate derivatives

The effectiveness of a phosphoramidate tetraethyl piperazine‐1,4‐diyldiphosphoramidate (TEPP) as a flame retardant on cotton twill fabrics was compared with that of a previously studied diethyl 4‐methylpiperazin‐1‐ylphosphoramidate (DEPP). TEPP was formed in a reaction between two phosphonates and a piperazine then cotton twill fabrics were treated with TEPP at different levels of add‐on (2–19 wt%) and characterized using vertical flammability, limiting oxygen index, microscale combustion calorimetry, and thermogravimetric analysis methods. The results showed better flame retardancy and thermal behavior for TEPP fabrics when compared with DEPP fabrics. When the morphological structure of the formed char from the burned areas was examined by scanning electron microscopy, the results revealed a fairly insignificant difference in the mode of action between the two types of fabric. Copyright © 2014 John Wiley & Sons, Ltd.     

Green synthesis and characterization of silver nanoparticles by Allium cepa L. to produce silver nano‐coated fabric and their antimicrobial evaluation

This research work was proposed to study the antimicrobial activity of the silver nanocoated fabric with the purpose of producing good dressing and clothing material. We synthesized simple, ecofriendly, cost‐effective and sustainable silver nanoparticles by using the aqueous extract of Allium cepa L. Here, A. cepa L. acts as a good reducing and capping agent that produced stable silver nanoparticles having particle size of range 36 ± 1 to 98 ± 2 nm, Poly dispersiblity index 0.234 ± 0.61 to 1.023 ± 0.33 and Zeta potential ‐12 ± 1.5 mV to ‐26 ± 1.2 mV. The effect of temperature and extract volume used was considered for optimization of synthetic procedure. The nanocoated fabric was characterized for morphological study, size (using transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE‐SEM) and zeta‐potential (Zeta Potentiometer). The presence of functional groups were observed by using attenuated total reflection‐Fourier transform infrared (ATR‐FTIR) and Raman spectroscopy. The crystallinity and structural property of the synthesized silver nanoparticles were studied in terms of Powder X‐ray diffraction (PXRD). An IC₅₀ value and zone of inhibition was studied which demonstrate that the silver nanocoated fabric have an excellent antibacterial property against Gram‐negative (Escherichia coli) and Gram‐positive (Staphylococcus aureus) bacteria. Further nanocoated fabric material was washed (with function of time 0, 10, 25, and 50 laundry cycles) and still retained their anti‐bacterial activity towards both strain. Initially there was 52 μg/ml of silver nanoparticles on the cotton fabric but after 50 laundry cycle in 500 ml of distilled water the fabric showed 92% efficiency against gram positive and 90% efficacy toward gram negative bacteria. It was found that 4.16 μg/ml nano particles leached in case of S. Aureus and 5.2 μg/mL silver nanoparticles leached in case of E. coli. Nanocoated fabric material synthesized using green synthesis was found to be economical with good resistance to washing.     

Compound Finishing of Bombyx mori Silk: A Study of Cold Oxygen Plasma/Titania Sols Treatments and Their Influences on Fiber Structure and Performance

Degummed Bombyx mori (B. mori) silk fabrics modified by cold oxygen plasma (COP) and/or titania sols (TSs) were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction, field emission scan electronic microscopy (FE-SEM), thermo-gravimetric and differential thermal analysis, and ultraviolet (UV) transmittance methods in this study. FT-IR analysis demonstrated that titania particles were associated with B. mori silk fibers by forming organic?Cinorganic hybrid blends. Processing sequences of COP and TSs, and curing conditions showed significant impacts on the crystalline, thermal, micro-morphological, and UV resistant characteristics of silk fabrics. Crystallinity index by both area and height methods, and crystallite sizes of silk fabrics were calculated as well. Results showed that crystallinity index of finished samples approximate to that of degummed silk fabric could be obtained by applying TSs and curing at 160?°C for 2?min prior to COP treatment, or vice versa with lower temperature of 140?°C for 3?min, whereas the crystallite sizes of treated samples increased slightly. The initial decomposition temperatures of finished samples were elevated by 23?C35?°C with increased char residues at 600?°C, while the transmittance of UVA and UVB of finished samples decreased by 11.7, 17.7%, respectively. FE-SEM analysis revealed that titania particles were associated on the fiber surfaces with different smoothness.