Uncoated Fabric Research Articles

Ultraviolet Protection and Antibacterial Properties of Polylactic Acid Nonwoven Fabrics Coated with Water-Borne Polyurethane/Zinc Oxide Composite Coatings

This study aimed to create thermally curable, water-borne polyurethane/zinc oxide (WPU/ZnO) composite coating pastes with varying ZnO concentrations. ZnO nanoparticles were synthesized using a wet chemical process, and the resulting WPU/ZnO coating pastes were applied to PLA nonwoven fabrics (NWFs). In characterization studies, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses were conducted. Ultraviolet (UV) protection and antibacterial activity of fabrics were investigated. With WPU/ZnO composite coatings, the UV protection properties of the coated fabrics were enhanced compared to the uncoated fabric. The highest UPF value of 53.57 was obtained with the fabric coated with the formulation containing a ZnO concentration of 10%. This fabric also demonstrated more effective antibacterial activity against both S. aureus and E. coli bacteria. Inhibition zone diameters against E. coli and S. aureus bacteria were measured as 15.5 ± 0.70 mm and 18.25 ± 0.35 mm, respectively. The results of this study illustrate that functional composite coatings for bio-based NWF structures hold great promise for producing effective UV protective and antibacterial materials, potentially setting the stage for future applications.

Development of bio-active cotton fabric coated with betalain extract as encapsulating agent for active packaging textiles

The development of bio-active cotton fabric based on natural polymers and pigments has been a significant material for biodegradable textile packaging in recent years. Betalain extracted (BE) from Red beet root (RBR) is a rich source of natural pigments and has potential health benefits as an antioxidant and in biological activities which used as food, beverage, and drug colorant. However, BE pigments are photochromically unstable and have interest applications, thereby motivating the use of microencapsulation technology to maintain their stability and increase their shelf lifetime. Thus, in the present work Incorporating BE into gelatinized corn starch (GS) and Arabic gum (AG) for manufacturing stabilized BE microcapsules with tunable antioxidant and biological properties by freeze-drying method. The produced encapsulating agent (EA) powders were analyzed by scanning electron microscope (SEM) for particle morphology and FTIR of selected EA was carried out. Monitoring of coloring strength values (K/S) and Color parameters before and after storage as well as storage stability of these microcapsules at different pH’s was also studied. The current study was performed to design multifunctional cotton fabric, for this purpose the cotton fabric was treated with keratin to improve its affinity toward 100 % BE, with and without (BE) EA were determined using a pad dry process. The chemical properties, physical properties, mechanical properties, thermal stability, and functional properties of the coated fabrics with and without (BE) as well as color parameters were determined. The results showed that the fabric coated with 100 % BE and 30 % BE incorporating or encapsulating with 60 % GS and 10 % AG exhibited good mechanical properties, excellent thermal stability, and significant antioxidant and antimicrobial activity compared to the uncoated fabric. The antioxidant release of BTE from the fabric coated with 60/10/30 EA was controlled by diffusion. According to the results, the developed multifunctional coated fabrics with BE encapsulating agent can be considered as a good potential material for active packaging textiles for various applications.

Bioinspired Diffuse Reflectance Coatings for Fabric-Based Radiative Coolers

As global temperatures rise due to anthropogenic climate change, thermal comfort becomes an increasingly critical area of research. While most buildings are equipped to cool and heat their interiors, this process is very energy intensive; a smarter approach is to enable personal thermal management using clothing and textiles. In particular, we are interested in the ability to use textiles and clothing to cool bodies in extreme heat, both to maintain comfort and prevent deaths in urban deserts due to heat stroke. One innovative category in this realm is radiative coolers—surfaces adept at manipulating light to passively regulate temperature. These coolers achieve sub-ambient surface temperatures by selectively reflecting or refracting sunlight wavelengths (200nm-2.5µm) while emitting infrared light (8-13µm). This unique capability allows them to maintain cooler temperatures, even when exposed to direct sunlight and the open sky. Coatings facilitating this cooling action typically consist of a porous media filled with refractive gaps, requiring specific substrates and custom production processes, thereby limiting their applications. Furthermore, the necessity of low light transmission presents issues in creating fabrics that radiatively cool while still retaining high breathability and durability. In this study we present a method whereby an optically active coating comprised of a mixture of CaCO3 and BaSO4 microcrystals was applied to multiple fabric substrates to create a radiative cooler. Through the use of photoinitiated chemical vapor deposition (pICVD), a 5 µm thick layer of a hydrophilic polymer polyhydroxyethyleneacrylate (pHEA) was deposited on the fabric substrate. Subsequently, through serial immersion in solutions containing Ca and Ba ions and solutions containing CO3 and SO4 ions, inorganic microcrystals were grown directly on the surface of the fabric. These microcrystals formed with a large polydispersity, endowing the coating with excellent reflective properties in the solar spectrum. Mie scattering calculations confirmed that the CaCO3 and BaSO4 microcrystals were primarily responsible for scattering. Further simulations using finite difference time domain software revealed, surprisingly, that surface-immobilized crystals provided the highest reflection efficiency, indicating that composite fibers with embedded particles are not as efficient. Upon outdoor testing, the device showed a cooling ability of 8°C compared to an uncoated fabric, achieving a maximum cooling of 4°C below ambient temperature. Washing and durability testing of the coating found no degradation in the material's performance, affirming its resilience and long-term effectiveness.

Smart Fabrics with Integrated Pathogen Detection, Repellency, and Antimicrobial Properties for Healthcare Applications

AbstractHealthcare textiles serve as key reservoirs for pathogen proliferation, demanding an urgent call for innovative interventions. Here, a new class of Smart Fabrics (SF) is introduced with integrated “Repel, Kill, and Detect” functionalities, achieved through a blend of hierarchically structured microparticles, modified nanoparticles, and an acidity‐responsive sensor. SF exhibit remarkable resilience against aerosol and droplet‐based pathogen transmission, showcasing a reduction exceeding 99.90% compared to uncoated fabrics across various drug‐resistant bacteria, Candida albicans, and Phi6 virus. Experiments involving bodily fluids from healthy and infected individuals reveal a significant reduction of 99.88% and 99.79% in clinical urine and feces samples, respectively, compared to uncoated fabrics. The SF's colorimetric detection capability coupled with machine learning (96.67% accuracy) ensures reliable pathogen identification, facilitating accurate differentiation between healthy and infected urine and fecal contaminated samples. SF holds promise for revolutionizing infection prevention and control in healthcare facilities, providing protection through early contamination detection.

Load-bearing behavior of short-fiber-reinforced textile-reinforced concrete for a wrapping process

In the research project titled Wrapping process for highly fiber-reinforced concrete using the example of a pump sump (WiFaPu), a new production process for components made of short-fiber-reinforced textile-reinforced concrete was developed. The idea of wrapping concrete continuously around a formwork evokes high-level requirements on the workability of concrete while matching reinforcement properties. In this study, the load-bearing behavior of wrappable short-fiber-reinforced textile-reinforced concrete with an uncoated textile reinforcement made of AR-glass is investigated via tensile and bending tests. The concrete inserted into the wrapped layers by casting, laminating or spraying and the short fiber content and warp/weft direction of the uncoated fabric have a major influence on the load-bearing behavior of the tested specimens with regard to the utilized tensile strength and crack spacing. Members produced by inserting the concrete in a spraying or laminating process showed low tensile strength and unsatisfactory cracking patterns in the warp direction of the fabric due to the lacing of rovings, which led to lower matrix penetration. For rovings in the weft direction without lacings, higher utilized tensile strengths and fine crack patterns are observed. The casting of specimens leads to significantly higher utilized textile tensile strengths if the reinforcement is slightly tightened in the formwork. Compacting fine-grained concrete leads to better roving penetration than does the spraying process. The addition of short fibers generally benefits the cracking pattern and partially compensates for the negative effects of the textile weave on the utilized tensile strength as well as on the warp direction of the crack pattern. The load increase in tensile and bending tests is proportional to the increase in short fiber content and fiber length. Finally, the influence of different coatings is examined for another uncoated textile reinforcement made of AR-glass with a more favorable textile weave. The utilized tensile strength of the reinforcement is almost doubled when impregnated with a fine cement suspension and directly installed in the formwork and cast. An impregnation process such as this can also be integrated into the wrapping process.

Improvement of thermal stability, flame retardancy, hydrophobicity, tear and wear performance of polyester fabrics with graphene nanoplatelet coating

AbstractIn this study, graphene nanoplatelets were applied to polyester fabrics using the knife‐coating method at different concentrations (50, 100, and 150 g/kg). SEM, DSC, and TGA/DTG analyses were performed. The influence of graphene coating on hydrophobicity and surface roughness was examined by water contact angle (WCA) measurement and root mean square roughness, respectively. Abrasion resistance and tear strength tests were also performed. The effect of graphene used as a filler on the flammability of polyester fabric was evaluated for the first time according to the BS 5852 standard. No significant weight loss (only in the range of 0.4%–1.5%) was observed in the graphene‐coated samples even after 100,000 cycles. While the WCA value was 0 for the uncoated fabric, the blind coating and maximum graphene‐coated sample measured 86° and 95°, respectively. The coating process reduced the roughness of the base fabric, and the decrease continued with the increasing graphene ratio. The tear strength values that were 45.5 N in the warp and 53.6 N in the weft direction in the blind coating, increased to 52.2 and 59.1 N, respectively, at the maximum graphene concentration. Graphene coating enhanced thermal stability, increased hydrophobicity, and improved flame retardancy in the test using a smoldering cigarette.

Innovative coating of cotton textile fabrics for integrating outstanding flame hazard safety, UV protection, tensile strength strengthening and antibacterial properties

A rational green synthesis method was developed to produce sustainable nanocoatings for cotton fabrics that are flame retardant, strengthened, antibacterial, and UV protective. The nanocoatings were created using silica nanoparticles with an average size of 73.2 nm derived from rice husk (RH-SNP). These nanoparticles were adorned with ZnONPs with an average size of 7.6 nm, which were reduced and capped with molokhia extract made from molokhia stems by-products. The ultimate nanocomposite was evenly distributed in a chitosan solution using ultrasonication. The mass ratio of RH-SNP in the nanocoating was adjusted and fine-tuned for optimization. The coated cotton fabrics were analyzed using spectroscopic and microscopic techniques. The flammability of cotton fabrics treated with sustainable coatings was assessed. The coated fabrics exhibited significantly greater flame retardancy, achieving a zero burning rate compared to 110 mm/min for the untreated one. The enhanced flame-retardant properties were a result of the combined flame-retardant effects of RH-SNP and molokhia stem extract, along with decorated ZnONPs, which created a more robust protective char layer. The coated cotton's antibacterial characteristics showed significant inhibition of bacterial growth, resulting in a 10 mm distinct inhibition zone, while pure cotton had no inhibition zone. Additionally, the coated cotton fabrics had exceptional UV shielding properties with a UPF rating of 167.8, which was more than fourth the value of the uncoated fabric. The tensile strength and elongation of the cotton fabrics were enhanced after applying a sustainable nanocoating, indicating a beneficial effect on tensile strength. Furthermore, the coated fabrics exhibited exceptional durability characteristics.

LOAD-BEARING BEHAVIOR OF SHORT-FIBER-REINFORCED TEXTILE CONCRETE FOR A WRAPPING PROCESS

In the research project WiFaPu (Wrapping Process for highly fiber-reinforced concrete using the example of a pump sump), a new manufacturing process for components made of Short-Fiber-Reinforced Textile Concrete is being developed. Wrapping concrete continuously around a formwork places high-level requirements on concrete and reinforcement properties. This paper presents the investigations on the load-bearing behavior of wrappable Short-Fiber-Reinforced Textile Concrete with uncoated textile reinforcement made of AR-glass in tensile tests. The placing of the concrete into the wrapped layers by casting, laminating or spraying as well as the short fiber content and warp/weft direction of the uncoated fabric have major influence on the load-bearing behavior of the tested specimens. Members produced in a spraying or laminating process showed low ultimate fabric stresses and unsatisfactory crack pattern in warp direction of the fabric due to the lacing of rovings leading to lower matrix penetration. Casting of specimens lead to significantly higher textile fracture stresses if textile fabrics are slightly tightened while installing in the formwork. Also vibrating the fine-grained concrete leads to better roving penetration compared to the spraying process. The addition of short fibers partially compensates negative effects of the textile weave in the warp direction.

LOAD-BEARING BEHAVIOR OF SHORT-FIBER-REINFORCED TEXTILE CONCRETE FOR A WRAPPING PROCESS

In the research project WiFaPu (Wrapping Process for highly fiber-reinforced concrete using the example of a pump sump), a new manufacturing process for components made of Short-Fiber-Reinforced Textile Concrete is being developed. Wrapping concrete continuously around a formwork places high-level requirements on concrete and reinforcement properties. This paper presents the investigations on the load-bearing behavior of wrappable Short-Fiber-Reinforced Textile Concrete with uncoated textile reinforcement made of AR-glass in tensile tests. The placing of the concrete into the wrapped layers by casting, laminating or spraying as well as the short fiber content and warp/weft direction of the uncoated fabric have major influence on the load-bearing behavior of the tested specimens. Members produced in a spraying or laminating process showed low ultimate fabric stresses and unsatisfactory crack pattern in warp direction of the fabric due to the lacing of rovings leading to lower matrix penetration. Casting of specimens lead to significantly higher textile fracture stresses if textile fabrics are slightly tightened while installing in the formwork. Also vibrating the fine-grained concrete leads to better roving penetration compared to the spraying process. The addition of short fibers partially compensates negative effects of the textile weave in the warp direction.

Surface modification of jute-cotton union fabric using TiO2 and ZnO nanoparticles for multifunctional properties

In this study TiO2 and ZnO nanoparticles were employed as a protective coating to impart multifunctional properties, i.e. self-cleaning, water repellency, UV protection and antimicrobial activity onto jute-cotton union fabric. Through the sol-gel method, using titanium (IV) isopropoxide (TTIP) and zinc acetate as precursors, TiO2 and ZnO nanoparticles have been synthesized. Following the dip-pad-dry-cure method along with a 2 wt% of acrylic binder, the synthesized particles were applied on the jute-cotton union fabric. Subsequently, antibacterial activity, self-cleaning properties and physical properties like water absorbency, crease recovery, water vapor permeability, tensile strength, and tear strength of the treated fabric were tested and evaluated. The structural properties of the nano-particles were distinguished by Fourier Transform Infrared Spectroscopy (FTIR) and SEM. Upon comparing the test results of the coated fabric with the uncoated fabric, the results were found to be extremely satisfactory. This study provided valuable insights into the potential of TiO2 and ZnO coating in enhancing properties of jute-cotton union fabric.

In Vitro and In Vivo Testing of Microbe Growth on Antimicrobial Nursing Scrubs.

Around 5% to 10% of hospitalized patients develop a hospital-acquired infection (HAI). Scrubs are a potential vector of HAIs. To compare the antimicrobial characteristics of scrubs with and without an antimicrobial fabric coating, as tested in the laboratory (in vitro) and hospital (in vivo) environments. Two protocols were conducted to address the purpose. The in vitro protocol was a laboratory study that involved observing the microbe growth after inoculating coated and uncoated scrub fabric swatches with S. aureus and then processing them in moist and dry environments. The in vivo protocol was a clinical trial that measured microbe growth on coated and uncoated scrubs prior to and following nursing staff completing a 12-hr shift on an acute care unit, as measured by colony forming units (CFUs). For high-humidity environments, the in vitro study indicated that swatches treated with an antimicrobial coating exhibited minimal microbe growth, while untreated swatches exhibited significant microbe growth. For low-humidity environments, coated and uncoated swatches were all found to exhibit minimal microbe growth. In the in vivo study, the CFUs increased on scrubs worn by nurses over a 12-hr shift with no significant difference in CFUs for coated and uncoated scrubs. For bacteria in a warm and moist environment, the antimicrobial coating was found to be important for inhibiting growth. For bacteria in a warm and dry environment, both coated and uncoated fabrics performed similarly as measured at 24 hr, with minimal bacterial growth observed. In a hospital environment, microbe growth was observed, but no significant difference was detected when comparing coated and uncoated scrubs. This may have been due to the short time between exposure and culturing the scrubs for analysis immediately at the end of the shift not allowing for enough time to kill or inhibit growth. Contact time between the bacteria and scrub fabric (coated or uncoated) in the in vivo study more directly correlated with the 0-hr observations for the in vitro study, suggesting that the ineffectiveness of the treated scrubs in the clinical results may be due in part to short residence times before collection.

Optimization and development of workwear fabric coated with TiO2 nanoparticles in order to improve thermal insulation properties and air permeability

Workwear clothing is one of the essential personal protective equipment for workers and plays a crucial role in preventing the entry of environmental heat into the body and facilitating thermal exchanges between the human body and the environment. Improving the coating of workwear fabrics while maintaining air permeability is considered an engineering control measure to protect workers in environments with thermal stress. This study aimed to optimize the coating of workwear fabrics with TiO2 nanoparticles to enhance thermal insulation properties and air permeability using the response surface methodology (RSM) and MATLAB. The input variables were the titanium isopropoxide volume and reaction time in the ultrasonic, while the output variables were the coating percent, air permeability, and thermal conductivity coefficients. The morphology of TiO2 nanoparticle and coated fabric (FE-SEM, EDS, FTIR, FTIR-ATR, DLS, and XRD), The intrinsic properties of fabrics (Yarn Count, Abrasion Resistance, Tensile, Tearing Strength), the Water Vapor permeability, Surface wetting resistance, and Durability test were evaluated according to the standard methods. No significant differences were observed in the intrinsic properties between the coated and uncoated fabrics. Increasing the coating percent of fabrics with TiO2 nanoparticles was accompanied with a decrease in the thermal conductivity coefficient and an increase in air permeability. The positive effect of nanoparticle coating is a significant step towards introducing a new generation of smart textiles with the potential to improve thermal insulation properties while maintaining air permeability. This advancement aims to preserve and enhance the health and safety of workers exposed to thermal stress.

Synergizing mechanical properties and vibrant aesthetics: Nanosilver-treated flax woven fabric reinforcement for polymeric composites

Innovation and research in the field of natural fiber-reinforced composites have garnered significant attention in recent times due to the pursuit of sustainable materials for diverse applications in the automotive, building and construction, marine, defense, and aviation industries. Woven fabric lamination has emerged as a crucial reinforcement technique for fabricating structural composites using thermosetting polymers. Advanced characteristics of nanoparticles renders them instrumental in enhancing the thermomechanical and physical properties of composites. Researches are actively going on to explore alternative approaches to develop AgNPs that are safe, environmentally friendly, and conducive to their integration into composites. In this study, hornbeam leaves (Carpinus betulus), abundant in central European countries like Hungary, were employed as a stabilizing and reducing agent to in situ synthesize AgNPs onto flax woven fabrics at varying concentrations. The resulting nanosilver-coated and uncoated fabrics were then laminated with MUF (melamine urea formaldehyde) resin using five layers of flax, thereby producing nanocomposites. Extensive analyses were conducted on the compositted products, encompassing inductively coupled plasma optical emission spectroscopy (iCP-OES), morphological examinations of both fractured and intact samples, assessment of mechanical properties, evaluation of physical characteristics (including water absorption, moisture content, and thickness swelling), thermal stability using TGA (Thermogravimetric analysis)/DTG (Derivative thermogravimetry) study, FTIR (Fourier transform infrared spectroscopy), and colorimetric data. The nanocomposites treated with AgNPs exhibited vibrant colors and uniform dispersion of nanoparticles across the surface compared to the control samples. These results suggest that AgNPs were successfully incorporated into flax-woven fabrics, facilitating the production of sustainable composite production.

Rational strategy for construction of multifunctional coatings for achieving high fire safety, antibacterial, UV protection and electrical conductivity functions of textile fabrics

Sustainable and innovative multifunctional organic coatings were designed and developed for integrating effective flame retardancy, ultraviolet (UV) radiation protection, electrical conductivity and antibacterial functions to viscose textiles. The coatings-based nanocomposites were prepared from cellulose nanocrystal phosphate derived from waste cotton clothes, graphene sheets derived from mandarin shell, polyaniline nanofibers and polypyrrole (PPy) and elucidated using microscopic and spectroscopic tools. The nanomaterials-based coatings were first synthesized individually from their sustainable precursors and then utilized in nanocoatings fabrication. Variety of nanocoatings were developed from different combinations of nanofillers and mass ratios and then coated on viscose textile fabrics. The flammability, thermal stability, UV protection, electrical conductivity and antibacterial properties of the treated textile fabrics were studied and optimized. The flame retardancy properties of the developed textile fabrics were significantly improved achieving zero rate of burning compared to 193 mm/min for uncoated fabrics. This outstanding fire safety was ascribed to synergistic flame retardancy effect of coating layer based phosphorylated cellulose nanocrystals, graphene sheets and polyaniline nanofibers affording protective char barrier. The flame retardancy action was further elucidated using scanning electron microscopy (SEM) and Raman spectroscopy of protective char layer developed. Moreover, the coated fabrics affords excellent UV protection properties achieving ultraviolet protection factor (UPF) value of 90 compared to 2.7 for uncoated one. Additionally, new electrical conductivity feature was incorporated to the developed fabrics achieving reduction in electrical resistivity by 10,000 time affording conductive fabrics with convenient dissipation factor. Interestingly, the fabricated nanocoating integrates superior antibacterial properties against different bacteria strains Staphylococcus aureus (Gram-positive) and E-coli (Gram-negative) achieving clear antibacterial inhibition zone of 14.5 and 18.4 mm compared to zero mm inhibition for untreated one respectively. Furthermore, the influence of different nanocoatings on tensile strength properties of coated fabrics was studied and optimized.

Tungsten-based hybrid nanocomposite thin film coated fabric for gamma, neutron, and X-ray attenuation

Ionizing radiation such as x-ray, γ-ray and neutron ray have serious negative health effects on human being. Hence, new and smart textile fabric nanocoating was facilely developed and coated on lab coat cloth. The newly hybrid nanocoatings were fabricated from uniform dispersion of PbWO4 NPs and Bi2WO6 NPs of an average sizes of 47.38 ± 7.6 and 9.1 ± 1.8 nm, respectively in chitosan solution. The dispersion of tungsten-based nanoparticles was performed using ultrasonication process, then well dispersed hybrid nanocoatings were coated on textile fabrics derived lab coat. The mass ratio of nanoparticles in nanocoatings were altered and optimized. The attenuation properties of x-ray/gamma ray and neutron ray were studied and achieving good shielding properties compared to uncoated fabrics. Additionally, the antibacterial and mechanical properties of coated fabrics were evaluated. The coated textile fabrics achieved clear inhibition zone of 4 mm compared to zero clear inhibition zone for uncoated ones against E-Coli. Moreover, the developed coating layer achieved good reinforcement effect recording superior tensile strength by 11.5% than uncoated sample. The dispersion properties of nanoparticles in coating nanocomposites were investigated using microscopic tools.

Study on the Hydrophobicity and Antibacterial Activity of Silica Sol-Chitosan-HDTMS Treated Cotton Fabric Dipped in an Aquas Media

A hydrophobic surface with an antibacterial property has numerous uses, including self-cleaning, anti-sticking, anti-contamination, sports apparel, and wound healing/implant materials. The durability of the coating in an aquas media (pH 7.4) is a vital requirement for use in technical textile sectors, particularly in medical applications. In this study, we used silica sol, chitosan and hexadecyltrimethoxysilane (HDTMS) to create exceptionally hydrophobic surfaces with antibacterial properties on cotton fabrics. First, cotton fabric was treated with silica sol, which was produced by the hydrolysis and condensation of tetraethoxysilane (TEOS) in an alkaline environment. After that, chitosan was applied on the silica sol-treated fabric to add an antibacterial characteristic. The silica sol-chitosan-treated fabric was then given a hydrolysed HDTMS treatment to give a highly hydrophobic property. The hydrophobicity was assessed by measuring the water contact angle, while the AATCC-147 test protocol was used to assess the antibacterial property. The developed fabric exhibited a strong hydrophobic property. The fabric samples were immersed in an aquas media for 30 days to assess the coating durability by observing changes in hydrophobicity and anti-bacterial activity in terms of the zone of inhibition (ZOI). After 30 days of immersion in the aquas media, it was observed that the contact angle decreased from 151.7° to 129.5°, and the ZOI increased from 1 mm to 5 mm, which indicates an increase in anti-bacterial activity in relation to time of immersion. The wicking characteristics of coated and uncoated fabrics were also measured to determine how coating affects the wicking behaviour of fabric. EDS was performed to observe the coating stability for coated-dipped fabric samples after 30 days. SEM analysis was performed to examine the surface morphology, while FTIR was used to determine the surface functional groups after coating and changes after dipping in the aquas media. The developed hydrophobic cotton fabrics with anti-bacterial properties may help in the fabrication of natural biomaterials and other technical textile products.

Flame retardation of polyester/cotton blended fabrics via intumescent sol-gel coatings

Sol-gel coatings have long been applied to improve the flame retardancy of fabrics, but they often exhibit unsatisfactory flame-retardant efficiency for polyester/cotton blended fabrics. Therefore, an intumescent coating called DAM was constructed in this work by modifying 3-aminopropyl triethoxysilane with amino phosphonates and melamine through neutralizition reaction of the ingredients. Then, DAM was deposited on the surface of the fabric as a homogeneous coating via sol-gel technique. It was found that DAM accelerated the dehydration of cotton at a relatively low temperature but did not influence the thermal decomposition of polyester. With DAM add-ons of 8% and 15%, the coated fabrics severally named DAM-8 and DAM-15, self-extinguished in horizontal and vertical flame tests, with liming oxygen index values of 23.0% and 26.0%, respectively. In the cone calorimetry test, the ignition of the fabric was slightly delayed owing to the presence of the DAM, while the total heat release and peak heat release rate of the DAM-15 were reduced by 26.1% and 46.3%, respectively. DAM showed flame-retardant activities in both condensed and gaseous phases. Hand assessment of the fabric via the PhabrOmeter system suggested that the presence of the DAM caused the coated fabric to be smoother but a little more rigid than the uncoated fabric.

UV protection properties of workwear fabrics coated with TiO2 nanoparticles.

The main purpose of this study was to evaluate the ultraviolet protective factor (UPF) of fabrics coated with TiO2 nanoparticles made using an in-situ synthesis method and more accurately assess the intrinsic properties of the textile. The cotton-polyester twill fabric (70–30%) (246.67 g/m2) was coated in-situ with TiO2 nanoparticles. In-situ coating is conducted in 4 steps; washing the fabrics, preparation of nanoparticles, injecting the nanoparticles into fabrics, and drying the fabric after coating. The scanning electron microscope (SEM) and X-ray diffraction (XRD), FTIR spectrometer, dynamic light scattering (DLS) and UV-Vis spectrophotometer were used to analyse the data of the coating and UPF results. Also, four standards such as ASTM D737, ISIRI 8332, ISIRI 4199, and ISIRI 567 were used for analyzing the intrinsic properties of a textile. The results of SEM, XRD and DLS altogether confirmed the in-situ formation of nanoparticles onto textile fibers. Moreover, the UPF value of the uncoated and coated fabrics was 3.67 and 55.82, respectively. It was shown that the in-situ deposition of TiO2 nanoparticles on fabric can provide adequate protection against UVR. Also, the results of analyzing the intrinsic properties of the textile showed that there were no significant differences in the intrinsic properties between the coated and uncoated fabrics. Based on the results, it can be concluded that the UV protective properties of workwear fabrics can be improved by coating TiO2 nanoparticles on them without any effect on the cooling effect of perspiration evaporation.

UV protection properties of workwear fabric coated with metal-organic frameworks

The main purpose of this study was to evaluate the ultraviolet protective factor (UPF) of fabrics coated with titanium-based metal-organic framework (MOFs) (NH2-MIL-125(Ti)) made using an In-situ synthesis method and more accurately assess the intrinsic properties of the fabric. The cotton-polyester twill fabric (70-30%) (246.67 g/m2) was coated. In-situ coating conducted in 4 steps washing the fabrics, preparation of MOFs, injecting the MOFs to fabrics, and drying the fabric after coating. The scanning electron microscope (SEM), FTIR spectrometer, dynamic light scattering (DLS) and UV-Vis spectrophotometer were used to analyses the data of coating and UPF results. Also, four standards such as ASTM D737, ISIRI 8332, ISIRI 4199, and ISIRI 567 were used for analyzing the intrinsic properties of the fabric. The results of SEM and DLS altogether confirmed the in-situ formation of MOFs onto the fabric fibers. Moreover, the UPF value of the uncoated and coated fabrics was 3.67 and 315.73, respectively. It was showed that the in-situ deposition of NH2-MIL-125(Ti) on fabric can provide adequate protection against UVR. Also, the results of analyzing the intrinsic properties of the fabric showed that there was no significant difference in the intrinsic properties between the coated and uncoated fabrics. Based on the results, it can be concluded that the UV protective property of workwear fabrics can be improved by coating NH2-MIL-125(Ti) on them without any effect on the cooling effect of perspiration evaporation.

A simple method for functionalization of polypyrrole-coated cotton fabrics by reduced graphene oxide for UV screening

Here, the modified Hummer’s method was used to prepare reduced graphene oxide (RGO) nanostructures. The functional properties of the prepared RGO nanostructures were studied by using the X-ray diffraction method (XRD), and scanning electron microscopy (SEM). Using the in situ polymerization process, polypyrrole (PPy) was prepared. During polymerization, an ultrasound-assisted coating process was used to coat the cotton fabrics. In addition, the Nafion@RGO composite mixture was deposited on the surface of PPy- coated cotton fabric by dip and dry method. The presence of cellulose crystal structure was confirmed by conducting a structural study of the coated and uncoated (UC) cotton fabrics. The presence of a characteristic functional group was confirmed by the Fourier transform infrared spectroscopy–Attenuated total reflection (FTIR–ATR) study of the fabrics. Wrinkled-like morphology with a proper binding of PPy with RGO was revealed by SEM analysis. Our results showed that the RGO coated fabrics could be distributed on the cotton fabric and possessed better thermal stability and wettability properties than uncoated cotton fabric. Ultraviolet (UV)-screening properties of the coated and uncoated fabrics confirmed the better performance of the coated cotton fabrics in the order of Nafion/RGO coated fabrics (RGPC) > PPy/Cotton (PC) > UC. The transmission and screening efficiency of RGO coated fabrics were 0.02% and 99.98%, respectively. Thus the Nafion/RGO/PPy fabrics is a safe and promising UV screening and have great potential application in the all wearable textile sector.