UV Blocking Research Articles

Sustainability and textiles are major upcoming areas in the world today. Textiles being the second largest economy generating as well as one of the polluting industries in India. Sustainable strategies are to be adopted for effective utilization of textile waste. Many attempts are being undertaken to find sustainable ways such as recycling fibres, yarns and fabrics. Textile fibres contribute nearly 4.6 % of the total pre-consumer waste materials being recycled in India. Agrotech is one of the fields of technical textiles which has gained importance in recent years. Hence, a study was undertaken in which needle punched non-woven fabric of 100%, 50:50 and 70:30 combinations was prepared using cotton waste fibers with wool waste, hemp waste, viscose rayon waste and natural nettle fiber waste fibers A comparative study of herbal finish treated and untreated composites was done. The results revealed that when herbal finish was applied on the developed composites and were tested on physical parameters as well as for specialised finishes; Hemp: Cotton 50:50 (herbal finish treated) combination showed 97% UV blocking and the moisture content increased to 11.7 % with good antimicrobial property. It was found that composites with herbal finish treatment showed better results and can be used for agrotech applications like shade nets, mulches, fruit covers and natural fruit ripeners.

Owing to its natural degradability and excellent film-forming characteristics, sodium alginate (SA) is gaining growing popularity in the field of food packaging. However, the insufficient antioxidant and antibacterial properties hinder its application. In the current research, protocatechuic acid (PCA) and Fe3+ were utilized to fabricate a metal polyphenol network structure. Subsequently, geranium essential oil emulsion (GEOE) was incorporated into the SA matrix, and SA-based films were prepared through the flat-sheet casting method. The impacts of PCA/Fe and various concentrations of GEOE on the physical, structural, as well as functional characteristics of SA-based films were comprehensively examined. The thickness of the prepared SA-based films was between 30 and 50 μm. The results showed that PCA/Fe, GEOE, and SA exhibited good biocompatibility, and the formed films were uniform. The incorporation of PCA/Fe and GEOE significantly improved the UV blocking ability, thermal stability, and antibacterial activity of SA-based films. In addition, PCA/Fe and GEOE enhanced the total antioxidant capacity of SA-based films from 3.5% to 88%. This research could provide some theoretical basis for the utilization of metal polyphenol networks and natural essential oils within the realm of food active packaging films.

Abstract This study investigates the effects of the isolated and combined addition of titanium dioxide (TiO2) and hexagonal boron nitride (hBN) nanoparticles on the thermal, mechanical, and optical properties of a linear low‐density polyethylene (LLDPE) and ethylene vinyl acetate (EVA) blend. Microscopy observations showed that hBN nanoparticles coarsened the co‐continuous LLDPE/EVA morphology. Thermal analysis revealed altered properties, including increased transition temperatures and reduced stability with nanoparticle incorporation. While individual nanoparticles had minimal effects on elastic modulus (E), their combined use increased E by 21% compared to pure LLDPE/EVA, indicating a synergistic effect. The results suggest that the location may have influenced the UV blocking. TiO2, effectively dispersed in EVA, enhanced UV‐B radiation blocking, whereas hBN showed less efficacy. The combination of TiO2 and hBN nanoparticles in LLDPE/EVA blends resulted in significant changes to the mechanical properties, suggesting a synergistic potential between the particles, with TiO2 being particularly effective in blocking UV‐B radiation.Highlights The combination of nanoparticles altered the thermal and mechanical properties. TiO2 showed greater effectiveness in blocking UV‐B. hBN influenced the co‐continuous morphology of the LLDPE/EVA blend. The dispersion of TiO2 in EVA was effective in blocking UV‐B radiation. Hybrid nanocomposites resulted in a 21% increase in Young's modulus.

In this study, we utilized Achillea Wilhelmsii C. Koch to extract its active components using a unique technique. These active substances were then employed to create a nanocomposite, with and without nano TiO2, using an electrospinning device. We examined the morphology of the resulting nanocomposite using a FESEM and found that the electrospinning method and conditions were appropriate. Moreover, we conducted an investigation and analysis of the anti-eczema effectiveness of both samples produced from the nanocomposite. Additionally, we compared and evaluated the strength, resistance to abrasion, and UV-blocking properties of the samples, and we generated them according to specific standards. In conclusion, the nanocomposite derived from Achillea Wilhelmsii C. Koch exhibited promising characteristics that could be applied in various industries.

Interband plasmons (IBPs) enable plasmonic behavior in nonmetallic materials, such as semiconductors. Originating from interband electronic transitions, IBPs are characterized by negative real permittivity that can extend into deep ultraviolet (DUV) spectrum, as demonstrated using silicon. However, the practical applications of IBPs are limited by their inherently broad resonances. In this study, we address this limitation by hybridizing the localized plasmon resonance of silicon nanostructures with the Fabry-Pérot resonance of a SiO2 dielectric layer atop a silicon substrate. This design achieves a simulated quality factor (Q-factor) of ∼43, with experimental measurements yielding a Q-factor of 37 at ∼4.6 eV within the DUV region. Furthermore, we demonstrate a 5.4-fold enhancement in DUV absorption for lignin-modified polyethylene glycol films when integrated with the hybridized DUV cavity, showcasing the potential for UV blocking applications. Our findings offer a versatile platform that can be adapted to other IBP systems and open new opportunities in UV-specific applications.

A strong, excellent water resistance, and anti-ultraviolet poly(vinyl alcohol)/lignocellulose/poly(butylene adipate-co-terephthalate) composite with "sandwich" structure.

An oxidative metal ions-free lignin-catalyzed multifunctional hydrogel bioelectronics for codable eye communication

A novel PVP-ALG/ZnO hydrogel nanocomposite film was synthesized using a solution casting method. By incorporating ZnO nanoparticles into a polyvinylpyrrolidone (PVP) and sodium alginate (ALG) hydrogel, the nanocomposite film demonstrated enhanced antimicrobial, mechanical and UV-blocking properties. Characterization techniques, including XRD, SEM, TEM and UTM, revealed an optimal tensile strength at a 0.0075 g ZnO composition. The composite exhibited superior swelling behaviour compared to pure PVP-ALG hydrogel in distilled water and buffer solution of pH 6.8. Drug-loading studies with cephalexin showed slower, sustained release under intestinal pH (6.8), attributed to ZnO-induced interactions. Antimicrobial analysis confirmed enhanced effectiveness and UV-blocking tests highlighted a high sun protection factor (SPF) of 7.9 for the nanocomposite film. The results highlighted the potential of the PVP-ALG/ZnO hydrogel as an excellent option for use in biomedical and pharmaceutical fields, especially for sustained drug delivery and protective applications.

CMX-0.04 composite films exhibited high UV (≈100%) and HEBL (≈97.5%) blocking performance with enhanced mechanical properties (303% and 830% increased tensile and Young's modulus, respectively) and excellent film flexibility.

This research examined the properties of a nanoweb created using the electrospinning technique, incorporating Halloysite clay nanotubes. The main focus was to understand how different vibration speeds affected the characteristics of the nanoweb. By utilizing FESEM and elemental mapping, it was confirmed that the Halloysite clay nanotubes were present and provided valuable insights into the structure of the samples. The results regarding electrical conductivity were remarkable, showing that the treated specimens had higher crease recovery properties compared to the untreated ones(more than 24%), thanks to the presence of Halloysite clay nanotubes and the different vibration speeds applied. In addition, the samples showed improved UV blocking capabilities up to about 75%, as well as exceptional strength (~33%) and abrasion resistance (~93%). Overall, the nanocomposite webs exhibited promising qualities that could have applications in various industries.

Bio-based waterborne polyurethanes from castor oil, sorbitan monooleate and sodium lignosulfonate with ultraviolet resistance, photothermal effect, corrosion protection and degradation properties

The influence of lignin's primary oxygen-containing functional groups, phenolic OH (Ph-OH) and methoxyl (OMe) groups, especially the Ph-OH/OMe ratio, on its UV absorptivity and long-lasting UV blocking remains unclear. In this study, organosolv lignins (OLs) with varying Ph-OH and OMe contents were prepared to evaluate their UV absorptivity and photostability by EPR (electron paramagnetic resonance). As the Ph-OH contents increased from 0.32 to 6.09 mmol/g, lignin with a higher Ph-OH content displayed better absorptivity with a strong correlation (Pearson's r = 0.95). However, an excessive Ph-OH content (>5.5 mmol/g) reduced the spin content of lignin, negatively affecting its photostability. Taking Ph-OH and OMe groups as the cofactor, OLs with Ph-OH/OMe ratios between 0.44 and 0.64 showed more favorable UV-blocking performance both in the initial state and after UV irradiation. Moreover, lignin-based sunscreens exhibited increasing SPF value even after 8 h of UV exposure, confirming lignin's long-lasting UV-blocking property.

Purpose: The study investigated the antioxidant, anti-inflammatory, photoprotective and skin-aging retardation activities of Asystasia vogeliana leaf n-hexane extract (AVHE) and its dechlorophyllized equivalent (DAVHE).Methods: The total phenolics, flavonoids, vitamin A and vitamin E contents of the extracts were quantified. Antioxidant (DPPH scavenging, ferric reducing antioxidant power, total antioxidant capacity, lipid peroxidation and metal chelating inhibition), anti-inflammatory (lipoxygenase, trypsin and protein denaturation inhibition), photoprotective (SPF and UV blocking) and skin-aging enzymes (collagenase and tyrosinase inhibition) activities were evaluated using standard methods. The components of the most potent extract were identified via GC-MS technique.Results: AVHE and DAVHE possess slight concentrations of total phenolics (9.89±0.21 mg GAE/g and 1.43±0.08 mg GAE/g),and flavonoids (0.68±0.00 mg GAE/g, 2.13±0.00 mg GAE/g); AVHE exhibited significantly higher vitamin A and E content (87.29±0.84 mg RE/g, 12.04±0.11 mgTE/g) than DAVHE (41.29±0.74 mgRE/g, 7.31±0.82 mg TE/g). Both extracts showed moderate antioxidant activity. AVHE demonstrated higher trypsin inhibition (81.44%±0.83), protein denaturation inhibition (62.07%±0.00) and lipoxygenase inhibition (IC50=0.458±0.041 mg/ml). Both extract had similar collagenase and tyrosinase inhibitory activities. AVHE showed a significantly higher sun photoprotective activity (46.35±0.55) than DAVHE (28.92±5.13) and a commercial sunscreen (11.65±0.01). GC-MS analysis identified major constituents in AVHE, including 9,12,15-octadecatrienoic acid, (Z,Z,Z); n-hexadecanoic acid; 1-octadecyne and phytol.Conclusion: A. vogeliana leaf n-hexane extract is a promising candidate for skin care formulation. However, dechlorophyllization slightly reduces its efficacy.

Sustainable and UV blocking edible films based on pea protein isolate and psyllium mucilage enriched with pomegranate peel extract

ABSTRACTPolyvinyl alcohol (PVA) films are widely used in industry, but they have limitations in mechanical strength, UV‐blocking, and antibacterial performance. This research addresses these challenges by integrating kraft lignin (KL) derivative and cellulose fibers (CFs) into PVA films. The results confirmed that KL enhanced UV blocking and hydrophobicity, but it reduced porosity and water absorption. Cationic KL (CKL) further improved UV‐blocking, hydrophilicity, antibacterial properties, and decreased oxygen permeability of the films. CF in PVA enhanced UV‐blocking and mechanical properties. It also improved hydrophilicity, aiding water absorption in lignin‐containing PVA films. CF also increased Young's modulus, oxygen permeability, and antibacterial properties. A 5 wt.% concentration of CF significantly enhanced oxygen barrier properties and mechanical strength, even though it reduced UV‐blocking. These findings highlighted the positive impact of lignin and cellulose derivatives in PVA films. However, due to high water absorption, these films may not be suitable for food packaging requiring moisture resistance.

Plasticized cellulose bioplastics with beeswax for the fabrication of multifunctional, biodegradable active food packaging

Abstract Polyvinyl alcohol (PVA) containing different levels of basic fuchsine (BF) was prepared using the solution casting method. Characterization via Fourier-transform infrared spectroscopy detailed changes in functional groups within the PVA/BF composites, indicates the hydrogen bonding between OH group of PVA and BF molecules. Optical investigations spanning the 190-2500 nm range demonstrated UV blocking properties in prepared PVA/BF composites (fromn 2.05 to 2.56 eV and from 4.08 to 6.32 eV). Moreover, the studies on optical band gap indicated a decrease with increased BF concentrations, reflecting altered electronic transitions within the prepared composites. The study also employed the single oscillator model provided by Wemple-DiDomenico to elucidate refractive index variations. After incorporating BF dye into the PVA polymer, the values of the dielectric constant as the frequency approaches infinity (ε∞), the dielectric constant of lattice (εL), dispersion energy (Ed), and oscillator energy (Eo) in PVA/BF composite samples showed an increase. Moreover, the nonlinear optical properties, including optical susceptibility and nonlinear refractive index were investigated and discussed. These findings underscore the versatility of PVA doped with BF for various applications including optical filters, and solar cell devices.

Active polyvinyl alcohol films with enhanced strength, antioxidant and antibacterial properties by incorporating nanocellulose and tannin

The integration of nanomaterials into the textile industry has significantly advanced the development of high-performance fabrics, offering enhanced properties such as UV blocking, fire resistance, breathability, hydrophobicity, antimicrobial activity, and dust rejection. In this context, our research explores the development and characterization of electrospun membranes composed of polyether ether ketone (PEEK) and various polyimides (PIs (1–6)), focusing on their application in protective clothing. The combination of phosphorus-containing polyimides and PEEK, along with the electrospinning process, enhances the distinctive properties of both PEEK and polyimides, leading to composite membranes that stand out according to key parameters essential for maintaining physiological balance. The structural and morphological characteristics of these membranes have been evaluated using Fourier transform infrared spectroscopy (FTIR) to identify the functional groups and scanning electron microscopy (SEM) to examine their morphology. These analyses provide critical insights into these materials’ properties, which influence key performance parameters such as moisture management, breathability, and barrier functions. The membranes’ breathability and impermeability were assessed through the water vapor transmission rate (WVTR), contact angle measurements, water and air permeability, and flame resistance tests. The results obtained indicate that PEEK/polyimide composite membranes meet the complex requirements of modern protective textiles, ensuring both safety and comfort for users through their optimized structural properties and enhanced functional capabilities.

Abstract. In northern China, exterior window glass significantly impacts heating energy consumption during winter by collecting heat and providing insulation. Additionally, it plays a crucial role in shading by attenuating ultraviolet rays. This paper presents an intelligent optimization algorithm based on genetic algorithms for optimizing the thickness of three-layer insulating glass to maximize solar radiation transmission and minimize ultraviolet radiation below 400nm wavelength, thereby enhancing the glass's heat collection and shading capabilities. The study utilizes MATLAB's genetic algorithm function, running 20 iterations to overcome local optima, achieving an optimal glass thickness configuration of 12mm for each layer. This configuration allows maximum solar energy transmission while substantially reducing UV radiation, balancing energy efficiency with health protection. Future research directions include examining different glass materials' effects on UV blocking, considering climate change impacts on glass performance, and scaling the optimization method for large-scale architectural applications to assess its practical and economic viability. The findings contribute to the development of energy-efficient and health-protective building materials.