Naimul Hasan
Textile Fabric Coatings for UV Protection
The swift advancement in the utilization of textile fabrics across diverse industrial and household contexts necessitates the integration of smart features to attain optimal comfort and safety attributes for end-users. One of the functions of this is to provide protection against harmful UV rays specially during the summer season, which can have detrimental effects on both human health and textile materials. In order to achieve this objective, it is necessary to integrate coatings designed for smart textile fabrics into textile apparel. Several treatment methods have been employed to coat textile surfaces, with the aim of endowing them with enhanced protection against deleterious ultraviolet radiation. In this article, we will discuss various treatment processes, including immersion, electrophoretic deposition, vacuum filtration deposition, dip-coating, and layer-by-layer techniques, used to apply textile fabric-based coatings such as graphene, spherical nanoparticles, and sustainable inorganic nanotubes. Graphene sheets, which are a type of sustainable material, were easily produced from renewable sources. Therefore, this article will concentrate on the potential of material-based coatings proposed for applications in UV protection. The UPF value can be easily assessed within the 280 nm to 400 nm range according to the Australian/New Zealand Standard (AS/NZS 4399:1996).
Graphene-Based Coatings
Since its production from graphite flakes, graphene (GRP) has proven to be an incredibly useful two-dimensional (2D) material due to the unique properties of its sp2 carbon atom structure. Graphene’s exceptional electronic, electrical, thermal, chemical, mechanical, and physical characteristics make it a viable material for use in a wide range of commercial settings. Graphene can be synthesized in a number of ways, both top-down and bottom-up, leading to single-layer graphene and multi-layer graphene sheets. Our most recent study includes the results of extensive research on the various methods of graphene synthesis. The GRP sheets were recently made using water-soluble polymers and sustainable precursors like biomass. According to reports, the GRP sheets made by recycling sugar beet leaves as biomass are an effective UV filter since they effectively block UV radiation while remaining transparent to visible light. This allows for a transparent UV filter that is not only adaptable but also smart and self-contained.
Researchers Hongtao Zhao et al. observed that unwashed polyamide weave fabric had a UPF rating of only 2.5, indicating that it is not very effective at shielding UV radiation. Electrophoretic deposition was used to apply the coating layer to the fabric’s surface, and graphene oxide (GO) nano-platelets were incorporated into the polyamide fabric. polyethylenimine was used to impart various polar groups into the fabric’s surface, hence facilitating the grafting propensity. Then, using a green hot-press method, GO was reduced on-site to produce reduced graphene oxide (rGO). With a UPF value of over 500, the created coating layer (polyamide/rGO nanocomposite) affords exceptional UV protection capabilities, around 200 times better than that of the control fabric. Even after being washed 10 times, the treated textile textiles maintained their durability attributes. In another experiment, knit polyester (PES) textiles were dipped in a solution containing GO, reduced GO (rGO), and rGO/silver nanoparticles. Stretchiness, foldability, and pliability were all significantly improved in the untreated materials. Polyester fabric coated with a nanocomposite of rGO/AgNPs contained little concentration of AgNPs (PES-rGO/Ag) achieved UV protection ability superior to that of polyester fabric coated with graphene oxide (PES-GO), and reduced the graphene oxide (PES-rGO) recording reduction in UV transmittance by 73%, 43%, and 33%, respectively. The synergistic impact of rGO and AgNPs may explain the improvement in UV blocking capabilities. In addition, Xiaoning Tang et al. polymerized the polyaniline layer after fabricating a cotton fabric coating based on GO nanosheets using vacuum filtration deposition (VFD). According to the findings, compared to GO-based coated cotton fabric and uncoated cotton fabric, PANI and GO incorporated into the cotton fabric (PANI-GO-cotton fabric) provides a remarkable UPF value of 445 with easy durability. This exemplifies the protection provided by the PANI layer against ultraviolet light. When the GO sheets were coated with zinc oxide quantum dot (ZnO QD), wrapped with polyvinyl alcohol (PVA), and used as green coating for cotton textiles, a synergistic UV blocking effect was produced. Compared to uncoated fabric (15), cotton fabric coated just with GO (40), and cotton fabric coated solely with ZnO QD (34), the UPF value of GO-ZnO QD-PVA-coated cotton textiles was determined to be 61.
Spherical Nanoparticles-Based Coatings
TiO2 nano particles (NPs), ZnO NPs, and SiO2 NPs are only a few examples of the spherical nanoparticles used widely as a UV protection coating for textile materials. TiO2 NPs is one of the most popular nanoparticles used in fabric treatments because of its many useful properties, including its ability to inhibit the growth of germs and fungi and to clean itself. This is because its band gap is optimised for absorbing radiation with a wavelength between 280 and 400 nm. Coatings of well distributed TiO2 NPs and ZnO NPs were described for a variety of textiles by Attia et al., both alone and in combination. The results showed that the UV protection capacity was drastically enhanced in comparison to the UPF values of 58, 9, and 20, respectively, recorded by pure cotton fibres and coating devoid of nanoparticles. Additionally, the coated textile textiles achieved remarkable antimicrobial capabilities. Alternatively, the same team had produced a textile fabric coating based on SiO2 NPs obtained from rice husk biomass, which they coated with silver nanoparticles and used as a UV protective layer. When comparing the UPF values of untreated cotton (9), coated cotton (124), and SiO2 NPs-AgNPs-free coating (20), the new coating provides a significant improvement for the treated cotton. Recently, it was discovered that while using SiO2 NPs-chitosan as a coating layer, the textural structure of the textile fabric significantly influenced the coating layer’s potential to protect damaging UV radiation.
However, it has been shown that antibacterial silver nanoparticles (AgNPs) added to a product have a UV protective effect. Therefore, the nanocomposite based on rGO-AgNPs applied to PET improved the fabric’s UV protection. Thus, the produced coated textiles registered a UPF value of 6145, as opposed to the UPF value of 34 obtained by pure cotton. The finished product eventually shows off both antibacterial and UV-filtering abilities. In addition, a fruit extract-based AgNPs-ZnO composite cotton fabric covering with effective UV protection and antibacterial capabilities was produced. Therefore, the UPF value for coated cotton was determined to be 70, while it was just 7.
Sustainable Nanotube-Based Coatings
Yet, there has been some focus on coatings with a single dimension for the purpose of adding UV protection to textiles. Attia et al. produced a coating for linen textile textiles, which are commonly used in historical textile conservation, using naturally occurring halloysite nanotubes (HNTs) adorned with molokhia extract. The green coating was evenly distributed throughout the linen’s surface and adhered to the cloth through supramolecular interactions. This meant that the produced linen textiles provided substantial protection from UV radiation, with a 57% increase in UPF factor compared to uncoated materials.
Notably, our team has recently devised a green and simple method for wrapping cellulose nanocrystals obtained from natural cotton fibres around HNTs, creating a transparent nanocomposite layer. The translucent green layer was then sprayed over HP, and its UV protection capabilities was shown to be superior to that of HP, with a UPF rating of 58 compared to 39 for unblemished HP, all without affecting the readability of the text. Sustainable development objectives (SDGs) that promote reliance on renewable precursors were adhered to in this method.
Mechanistic UV Protection Action
The coating layer’s UV protective chemicals always absorb UV rays and/or reflect UV rays to provide the necessary UV protection. Therefore, the gap between the valence and conduction bands of these materials mostly governs the absorption propensity of these materials. However, the structure and crystallinity played a crucial impact in the performance of UV ray reflection for those materials whose primary function was based on the reflection trend. Therefore, the band gap of semiconducting materials must be regulated by engineering of the band gap in order to provide high UV blocking performance for the first class of UV protective agents. For UV absorption, it is common practise to decorate and dope such materials with unusual metal nanoparticles capable of bridging the gap and therefore decreasing the band gap. Fabricating a coating layer based on nanocomposites rather than a single com- ponent offers a novel synergistic characteristic for UV reflection action materials.
UV rays are a major contributor to the degradation of natural and manufactured materials over time. Therefore, they need to be filtered before they can be sold to the public. Natural and synthetic textile textiles are among the sensitive materials used in a wide range of contexts, from medical research to archival preservation. Sustainable textile fabric coatings for the preservation of a wide range of textiles were the topic of discussion in this overview. The use of coatings made of graphene sheets, a special 2D material with organic origins, to block ultraviolet light has received some attention. Additionally, the feasibility of filtering out UV radiation and their damaging effects using naturally occurring inorganic nanotubes, silica nanoparticles, and cellulose nanocrystals was investigated. The most important measures for preventing UV damage were also suggested.
References
- Attia, N. F., Osama, R., Elashery, S. E., Kalam, A., Al-Sehemi, A. G., & Algarni, H. (2022). Recent Advances of Sustainable Textile Fabric Coatings for UV Protection Properties. Coatings, 12(10), 1597.
- Attia, N.F.; Rao, J.P.; Geckeler, K.E. Nanodiamond–polymer nanoparticle composites and their thin films. J. Nanopart. Res. 2014, 16, 2361.
- Attia, N.F.; Soliman, M.H.; El-Sakka, S.S. Facile Route for synthesis of novel flame retardant, reinforcement and antibacterial textile fabrics coatings. Coatings 2020, 10, 576.
- Tang, X.; Tian, M.; Qu, L.; Zhu, S.; Guo, X.; Han, G.; Sun, K.; Hu, X.; Wang, Y.; Xu, X. Functionalization of cotton fabric with graphene oxide nanosheet and polyaniline for conductive and UV blocking properties. Synth. Met. 2015, 202, 82–88.
- Zhao, H.; Tian, M.; Hao, Y.; Qu, L.; Zhu, S.; Chen, S. Fast and facile graphene oxide grafting on hydrophobic polyamide fabric via electrophoretic deposition route. J. Mater. Sci. 2018, 53, 9504–9520.
