UV Protection Properties Research Articles

Antibacterial Superhydrophobic Cotton Fabric with Photothermal, Self-Cleaning, and Ultraviolet Protection Functionalities.

Cotton fabrics with superhydrophobic, antibacterial, UV protection, and photothermal properties were developed using Ag/PDMS coatings, and the role of coating formulations on the obtained functionalities was studied. Specific attention was paid to understanding the relationships between the fabrics' superhydrophobicity and antibacterial activity against Escherichia coli (E. coli) bacteria. UV protection performance of Ag/PDMS coatings was thoroughly evaluated based on the variation of UV transmission rate through coated fabrics and photoinduced chemiluminescence spectra. Moreover, the effect of silver nanoparticles (Ag NPs) and PDMS on developing a photothermal effect on fabrics was discussed. It was found that the content of Ag NPs and PDMS played critical roles in determining the water contact angle (WCA) on modified fabrics. The largest WCA was 171.31°, which was durable even after numerous accelerated wash cycles and abrasions. Antibacterial activity of fabrics showed the positive effect of pure PDMS in bacterial growth inhibition. Moreover, it was found that the antibacterial performance was greatly affected by the content of Ag NPs loaded on fabrics rather than their superhydrophobic status. Moreover, increasing the content of Ag NPs boosted the UV protection level of fabrics, improved fabrics photostability, and reduced the UV transmission rate through fabrics. Testing the photothermal effect confirmed that the content of Ag NPs and PDMS both played prominent roles, where Ag acted as a photothermal agent and PDMS determined the NIR reflection rate from the coated surface. The modified fabrics were characterized using TGA, SEM, FTIR, and XRD techniques, and it was confirmed that using a higher amount of PDMS increased the amount of Ag NPs deposition on fabrics.

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.

Preparation of chitosan/gelatin-based functional films integrated with carbon dots from banana peel for active packaging application

Carbon dots (CDs) were manufactured with banana peels using a hydrothermal method (200 °C for 6 h). The synthesized CDs were spherical particles with a size of 1–3 nm having carboxyl groups and amine groups on the surface. CDs have been impregnated into chitosan/gelatin films to synthesize multifunctional packaging films. The composite film showed a slight decrease in transparency but a significant increase in UV protection properties. The fabricated film displayed strong antioxidant efficacy showing >74 % DPPH and 99 % ABTS radical scavenging potential. The film also unveiled substantial antibacterial activity against the foodborne pathogenic bacteria, Listeria monocytogenes, fully eliminating the growth of these bacteria within 6 h of exposure. The chitosan/gelatin film containing CD was used for minced meat packaging, and the film delayed bacterial growth (< 1 Log CFU/g after 24 h) and maintained the meat color even after 24 h of storage at 20 °C. The CD-added chitosan/gelatin functional film has a high probability of application in active food packaging, especially for extending the shelf life of packaged meat and maintaining its aesthetic quality.

Dyeing of Silk with Natural Lac Dye from Laccifer lacca Kerr. and Evaluation of Antibacterial and UV-Protective Properties

Dyeing of Silk with Natural Lac Dye from Laccifer lacca Kerr. and Evaluation of Antibacterial and UV-Protective Properties

Fully Biobased Polyhydroxyalkanoate/Tannin Films as Multifunctional Materials for Smart Food Packaging Applications.

Fully biobased and biodegradable materials have attracted a growing interest in the food packaging sector as they can help to reduce the negative impact of fossil-based plastics on the environment. Moreover, the addition of functionalities to these materials by introducing active molecules has become an essential requirement to create modern packaging able to extend food's shelf-life while informing the consumer about food quality and freshness. In this study, we present an innovative bioplastic formulation for food packaging based on poly(hydroxybutyrate-co-valerate) (PHBV) and tannins as multifunctional additives. As a proof of concept, PHBV/tannin films were prepared by solvent casting, increasing the tannin content from 1 to 10 per hundred of resin (phr). Formic acid was used to reach a homogeneous distribution of the hydrophilic tannins into hydrophobic PHBV, which is remarkably challenging by using other solvents. Thanks to their well-known properties, the effect of tannins on the antioxidant, UV protection, and gas barrier properties of PHBV was evaluated. Samples containing 5 phr bioadditive revealed the best combination of these properties, also maintaining good transparency. Differential scanning calorimetry (DSC) investigations revealed that films are suitable for application from the fridge to potentially high temperatures for food heating (up to 200 °C). Tensile tests have also shown that Young's modulus (900-1030 MPa) and tensile strength (20 MPa) are comparable with those of the common polymers and biopolymers for packaging. Besides the improvement of the PHBV properties for extending food's shelf-life, it was also observed that PHBV/tannin could colorimetrically detect ammonia vapors, thus making this material potentially applicable as a smart indicator for food spoilage (e.g., detection of fish degradation). The presented outcomes suggest that tannins can add multifunctional properties to a polymeric material, opening up a new strategy to obtain an attractive alternative to petroleum-based plastics for smart food packaging applications.

The Preparation of Self-Cleaning Wool-Fiber–TiO2-Pillared Montmorillonite Composites with UV-Protection Properties

The Preparation of Self-Cleaning Wool-Fiber–TiO2-Pillared Montmorillonite Composites with UV-Protection Properties

Coinage Metals Doped ZnO Obtained by Sol-Gel Method—A Brief Review

ZnO is one of the most studied oxides due to its nontoxic nature and remarkable properties. It has antibacterial and UV-protection properties, high thermal conductivity, and high refractive index. Various ways have been used to synthesize and fabricate coinage metals doped ZnO, but the sol-gel technique has received a lot of interest because of its safety, low cost, and facile deposition equipment. Coinage metals are represented by the three nonradioactive elements of group 11 of the periodic table: gold, silver, and copper. This paper, which was motivated by the lack of reviews on the topic, provides a summary of the synthesis of Cu, Ag, and Au-doped ZnO nanostructures with an emphasis on the sol-gel process and identifies the numerous factors that affect the morphological, structural, optical, electrical, and magnetic properties of the produced materials. This is accomplished by tabulating and discussing a summary of a number of parameters and applications that were published in the existing literature over the previous five years (2017-2022). The main applications being pursued involve biomaterials, photocatalysts, energy storage materials, and microelectronics. This review ought to serve as a helpful reference point for researchers looking into the many physicochemical characteristics of coinage metals doped ZnO, as well as how these characteristics vary according to the conditions under which experiments are conducted.

Responsive polymer thin films

Responsive polymer thin films

Silk textile finished with natural dyes and UV resistance agents from agricultural waste Aloe vera rinds

Aloe vera is an agricultural resource widely used in many fields, but it has not been fully exploited as a biological dye in textile substrates. This work explored an approach for using Aloe vera rinds (AVRs) for the simultaneous dyeing and UV-protective functional finishing of silk fabrics. The optimal extraction conditions and the chemical composition of Aloe vera dye (AVD) were investigated. The colour parameters, colour-fastness, and UV-protective properties of silk fabrics dyed with AVD were tested. The results showed that the extracts mainly included polyphenols and flavonoids. The dyed fabrics obtained a colour depth (K/S) of 7.9447 and > 4 grades of colour-fastness to washing and rubbing without using a mordant. The dyed fabrics exhibited a surprising ultraviolet protection factor (UPF) of 2075.76 and remained at 1241.23 after 25 washing cycles, which was much higher than standard recommended. This research provides a method for the value-added management of agricultural waste for natural dyeing and functional finishing of textiles.

Functionalization of silk with chitosan and Rubia cordifolia L. dye extract for enhanced antimicrobial and ultraviolet protective properties

Natural dyes have attained the interest of scientists over the last decade due to their functional activities in addition to their primary role of color impartation on textile materials. This study is the first report on the functionalization of silk with antimicrobial and ultraviolet protective properties using a dye extract from the roots of Rubia cordifolia L. in conjunction with chitosan as a bio-mordant. Alum mordant was also used in the dyeing process alongside chitosan for comparison purposes. Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy were utilized to determine the anthraquinone-based components of the dye extract. Furthermore, the structure and surface morphology of silk fibers before and after dyeing were investigated. The dyed silk samples exhibited good fastness against washing, rubbing, and lighting. The chitosan mordanted-dyed silk presented remarkable antimicrobial properties with maximum inhibitions of 96.71% and 99.08% against Escherichia coli and Staphylococcus aureus, respectively, and only 2.3% spore germination of white mold ( Aspergillus spp.). Likewise, an excellent ultraviolet protection factor was achieved in the chitosan modified-dyed silk. The findings of this study demonstrated the potential of the Rubia cordifolia L. extract as a functional dye, as well as the advanced properties of chitosan in increasing the fastness and functional performance for the dyed silk compared to alum mordant.

UV–Visible–NIR camouflage textiles with natural plant based natural dyes on natural fibre against woodland combat background for defence protection

Woodland combat background (CB) is a common source of natural plant based natural dyes (NPND). Swietenia Macrophylla, Mangifera Indica, Terminalia Arjuna, Corchorus Capsularis, Camellia Sinensis, Azadirachta Indica, Acacia Acuminata, Areca Catechu and Cinnamomum Tamala were dried-grinded-powdered-extracted-polyaziridine encapsulated-dyed-coated-printed with leafy design on cotton fabric and tested against woodland CB under the reflection engineering of ultraviolet (UV)–visible (Vis)–near infrared (NIR) spectrums and photographic versus chromatic techniques of Vis imaging. The reflection properties of NPND treated and untreated cotton fabric were experimented by UV–Vis–NIR spectrophotometer from 220 to 1400 nm. Six segments of field trialling for NPND treated woodland camouflage textiles were also investigated for concealment, detection, recognition and identification of target signature against forest plants/herbs species; common tree of woodland CB such as Shorea Robusta Gaertn, Bamboo Vulgaris, Musa Acuminata; and a wooden bridge made by Eucalyptus Citriodora & Bamboo Vulgaris. The imaging properties such as CIE L*, a*, b* and RGB (red, green, blue) of NPND treated cotton-garments were captured by digital camera from 400 to 700 nm against tree stem/bark, dry leaves, green leaves and dry wood of woodland CB. Therefore, a colorful matching for concealment, detection, recognition and identification of target signature against woodland CB was verified by Vis camera imaging and UV–Vis–NIR reflection mechanism. UV-protection property of Swietenia Macrophylla treated cotton fabric was also investigated by diffuse reflection for defence clothing. Simultaneous ‘camouflage textiles in UV–Vis–NIR’ and ‘UV-protective’ property of Swietenia Macrophylla treated fabric have been investigated for NPND materials-based textiles coloration (dyeing-coating-printing) which is a new concept for camouflage formulation of NPND dyed-NPND mordanted-NPND coated-NPND printed textiles in terms of ecofriendly source of woodland camouflage materials. Therefore, technical properties of NPND materials and methodologies of camouflage textile assessment have been advanced in addition to coloration philosophy of natural dyed-coated-printed textiles.

Polyacrylic Acid and Chitosan Treatments on Silk Fabric for Protection Enhancements

Silk is utilized as most valuable fibers based on the unique properties like shiny sheen, remarkable comfort performance and bio considerations. Silk materials possess high applications as a natural substrate in the textile/garment industry and as a bio component in the medical applications. As silk is fine, delicate and sensitive it needs more care to protect from the ill effects of insects, light and chemicals. Hence, in this work an attempt is carried out on silk fabric by treatment with polyacrylic acid and chitosan followed by dyeing using few natural dyes and one synthetic reactive dye and subsequently subjected for different tests towards physical properties, colorimetric and fastness properties, low stress mechanical properties, antimicrobial and uv protection properties, SEM and XRD studies. The results of these tests give very good improvement of the protection behavior on the silk fabric suitable for the garments and other end use products.

Electrospun PVA membranes reinforced with cellulose nanocrystals and thermally reduced graphene oxide: Thermal, mechanical and UV-protection properties

Polyvinyl alcohol (PVA) has been widely proposed as biodegradable films, but it suffers rapid UV degradation affecting mechanical properties, low water resistance and poor antimicrobial properties. To overcome these difficulties, it has been blend with nanocrystalline cellulose (CNC) to produce nanocomposite membranes; however, adding a third element such as reduced graphene oxide (rGO) to the blend with potential packaging applications has not been reported. Herein, CNC was isolated from agroindustrial wastes (sugarcane bagasse; SCB) and used along with thermally reduced graphene oxide (TrGO) to be incorporated into PVA for the production of electrospun membranes for packaging applications. A wide variety of electrospinning parameters were analyzed to obtain PVA:CNC:TrGO composite membranes and their effects on thermal stability, mechanical properties, UV protection and moisture absorption, were evaluated. The results show that the isolation of CNC from SCB presented two phases: monoclinic and triclinic of type I cellulose. The highest crystallinity index (78.96%) and the diameter (10–20 nm)-length (150–200 nm) relation were found at 50 °C using a fiber:acid solution ratio of 1:50. In the case of ternary composite membranes, only free-defect morphologies with a composition of 84.5:15.0:0.5 wt% (PVA:CNC:TrGO) were observed. As a result of the adequate orientation and dispersion of the CNC:TrGO in the PVA matrix an improved was observed in the thermal stability, mechanical (137.48 MPa, HIT), UV barrier (up to 6% compared to pure PVA) and moisture absorption (reducing from 4.8% to 0.05%) properties. The eco-friendly structured ternary nanocomposites support the desired properties to produce food packaging materials.

Design and fabrication of metal-organic-framework based coatings for high fire safety and UV protection, reinforcement and electrical conductivity properties of textile fabrics

Rational design and fabrication of multifunctional textile fabrics coatings were developed. The green coatings were facilely prepared from metal-organic-framework UiO-66 as porous crystalline framework which was easily decorated with green spherical polypyrrole nanoparticles of an average size of 165 nm and then wrapped with chitosan chains. The nanocomposites were synthesized in one-step method with the aid of cost-effective ultrasonication method to facilitate the individualization of polypyrrole nanoparticles and their decoration on UiO-66 surface. The as developed coating was then coated on cotton fabrics. The structure and crystalline structure of UiO-66 were elucidated, also the structure and morphological properties of polypyrrole nanoparticles were studied using FT-IR, XRD and SEM. The mass loadings of UiO-66 and polypyrrole nanoparticles were varied and their influence was studied. The flammability, thermal stability, mechanical properties, UV protection and electrical conductivity of coated textiles were studied. The newly developed multifunctional coating affords high flame retardancy to coated cotton fabrics achieving reduction in rate of burning by 54 % compared to uncoated sample. Significant thermal stability was attained recording 23 °C increase in temperature of maximum mass loss. Besides, the tensile strength of coated sample achieved 29 % improvement compared to uncoated one. Moreover, outstanding UV protection feature for coated cotton fabrics was obtained recording more than two-fold enhancement in ultraviolet protection factor compared to pristine sample. Interestingly, the smart coating layer fabricated on cotton fabrics impregnated the fabrics with electrical conductivity property recording electrical resistance of 2 MΩ compared to 45 MΩ for pristine fabrics. Additionally, the flame retardancy action was fully studied and elucidated.

Synthesis of a Novel Cationic Dye to Impart Mosquito-Repellent and UV Protection to an Acrylic Fabric.

The growing demand for innovative routes to develop functional textiles initiated the necessity of new efficient functional molecules. Dyes can provide durable functional protection to textiles due to their ability to generate strong dye-fiber interaction. New dyes to improve a dyed substrate's quality and aesthetic appearance are in huge demand. This research aims to prepare a mosquito-repellent and UV-protective acrylic fabric using a novel cationic (basic) dye. The cationic dye was synthesized and thoroughly characterized with the help of FTIR, 1H NMR, 13C NMR, and CHN analysis. The dye was further used for the dyeing of the acrylic fabric by using an infrared dyeing machine. To analyze the suitability of dyed fabrics for daily use, washing, rubbing, and light fastness of dyed fabrics were determined. The amount of dye (%) taken up by the acrylic fabric (exhaustion %) was determined, and more than 72% of exhaustion was obtained. The fixation (%) of the dye on acrylic fabrics was also quantified, and more than 80% fixation was obtained. The coloration properties of the dyed fabrics (L*, a*, b*, and K/S) were examined. The dyed fabrics showed a K/S of more than 3. The mosquito-repellent action provided by the dyed fabrics was also analyzed, and 100% repellency was obtained. The dyed fabrics provided an excellent UV-protective property. The multifunctional properties of dyed fabrics were retained significantly even after laundering treatments. The dyed fabrics were characterized using X-ray diffraction and thermogravimetric analysis. A reduction in crystalline peak intensity after dyeing was obtained. The dyed and undyed fabrics were also tested for their tensile strength.

Double-shell lignin microcapsules were prepared by one - step method for fabric coatings with UV resistance and durable antibacterial activity

The design and application of intelligent biomass microcapsules have gradually attracted widespread attention. In this study, double shell lignin microcapsules (DSLM) were prepared in one step by combining interfacial polymerization with free radical copolymerization. The biomass material lignin was grafted into the polyurethane shell at the interfacial polymerization stage to endow the microcapsule with a certain ultraviolet (UV) protection function. Lemon essential oil (LEO) with fragrance and antibacterial properties was further located at the core of the microcapsule and released by the thermal response. In the study, the morphological structure of the microcapsules and the release of the core material as well as the core-shell framework were characterized. Furthermore, these microcapsules were applied to the fabric coatings to give it UV protection and antibacterial properties. The whole preparation and functionalization process is facile and environmentally friendly. Due to the double-shell design, the encapsulated lemon essential oil is not easy to leak, which extends the antibacterial time and service life of the fabric coatings, and the release of the core material was controlled. At the same time, the outer shell of microcapsule plays a double protective role. These smart microcapsules are expected to be applied in outdoor fabric coatings and daily necessities in the future.

Cleaner pathway for developing bioactive textile materials using natural dyes: a review

Bioactive textile materials are a promising field in the development of functional textiles. The integration of bioactive compounds, such as natural dyes, into textiles offers a range of benefits, including UV protection, anti-microbial properties, and insect repellency. Natural dyes have been shown to have bioactivity, and their integration into textiles has been extensively studied. The application of natural dyes on textile substrates will be an advantage for their inherent functional properties along with their non-toxic and eco-friendly nature. This review addresses the effect of natural dyes on surface modification of most used natural and synthetic fibers and its subsequent effects on their anti-microbial, UV protection and insect repellent properties with natural dyes. Natural dyes have proved to be environmentally friendly in an attempt to improve bioactive functions in textile materials. This review provides a clear view of sustainable resources for the dyeing and finishing of textiles to develop a cleaner pathway of bioactive textiles using natural dyes. Furthermore, the dye source, advantages and disadvantages of natural dye, main dye component, and chemical structure are listed. However, there is still a need for interdisciplinary research to further optimize the integration of natural dyes into textiles and to improve their bioactivity, biocompatibility, and sustainability. The development of bioactive textile materials using natural dyes has the potential to revolutionize the textile industry and to provide a range of benefits to consumers and society.

Effect of metal ion on UV protective and antimicrobial properties of in-situ synthesized pyrithione complexes on cellulosic textiles

Effect of metal ion on UV protective and antimicrobial properties of in-situ synthesized pyrithione complexes on cellulosic textiles

Prospects of ZnS and ZnO as smart semiconductor materials in light-activated antimicrobial coatings for mitigation of severe acute respiratory syndrome coronavirus-2 infection.

We carried out theoretical and experimental analyses of ZnO and ZnS nanoparticles as smart semiconductor materials in light-activated antimicrobial coating for application in masks. We used low-cost hydrothermally processable precursors to direct the growth of the coatings on cotton fabric. Both ZnO and ZnS coatings had high reactivities as disinfection agents in photocatalysis reactions for the degradation of a methylene blue dye solution. Also, these coatings showed excellent UV protection properties. For understanding at the molecular level, the broad-spectrum biological activities of the ZnO and ZnS coatings against Fusarium Oxysporum fungi, Escherichia coli bacteria, and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus and their variants, were investigated computationally. Hexagonal Zn6O6 and Zn6S6 clusters were used as models for the simulations through excited- and ground-state calculations. The theoretical findings show that changes in the local chemical environment in these excited systems have a profound impact on their physical and chemical properties and thus, can provide a better understanding to engineer new functional materials in light-activated antimicrobial coatings for the mitigation of SARS-CoV-2 infection.

Investigation of The Protective Properties of Bacteria (Agrococcus Citrus) and Fungus (Fusarium Oxysporium) Pigments ın Lettuce Plant Exposed to UV Stress

As a result of climate change and the ozone layer spoilage, harmful rays of the sun such as UV reach the world more and harm agricultural production. To be protected from the harmful effects of UV, not only human beings, but all living organisms have developed different characteristics. In recent years, pigments with radiation absorbing and antioxidant properties have been used against UV damages. In this study, the effect of carotenoid pigments obtained from bacteria and fungi on the lettuce plant (Lettuce Yedikule 5701) was investigated due to its high antioxidant and UV protection properties. Pigment solutions partially purified from microorganisms were sprayed onto the plants. While an increase was detected in the amounts of hydrogen peroxide (H2O2) and lipid peroxidation (LPO) in the lettuce plant with the effect of UV, a decrease was observed in these parameters when applied with pigment solutions. With the same application, microbial pigments protected the plant against the harmful effects of UV by increasing the antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POX) and the amount of chlorophyll.&#x0D; As a result of this study; It has been determined that microbial pigments, which can be obtained easily and with low costs, have protection properties against the harmful effects of UV and provide the plants with properties to resist the stress.