A facile method to prepare hybrid cellulose acetate nanofibers containing TiO2 (TiO2-CA nanofibers) by emulsion electrospinning technique was developed for the denitrification and filtration of particulate matters (PMs). This work found that hybrid TiO2-CA nanofibers mainly contain the anatase form of TiO2, contributing to the photodecomposition of NO gas under UV irradiation. The TiO2-CA nanofibers also showed an excellent filtration efficiency of 99.5% for PM0.5 and a photocatalytic efficiency of 78.6% for NO removal. Furthermore, the results implied that the morphology of the TiO2-CA nanofibers, such as micro-wrinkles and protrusions, increased the surface hydrophobicity up to 140°, with the increased addition of TiO2 nanoparticles. The proposed TiO2-CA nanofibers, as a result, would be promising materials for highly efficient and sustainable air filters for industrial and home appliance systems.
Microplastics reach the aquatic environment through wastewater. Larger debris is removed in sewage treatment plants, but filters are not explicitly designed to retain sewage sludge’s microplastic or terrestrial soils. Therefore, the effective quantification of filtration system to mitigate microplastics is needed. To mitigate microplastics, various devices have been designed, and the removal efficiency of devices was compared. However, this study focused on identifying different fabrics that shed fewer microplastics. Therefore, in this study, fabric-specific analyses of microplastics of three different fabrics during washing and drying processes were studied. Also, the change in the generation of microplastics for each washing process of standard washing was investigated. The amount of microplastics released according to the washing process was analyzed, and the collected microplastics’ weight, length, and diameter were measured and recorded. According to the different types of yarn, the amount of microplastic fibers produced during washing and drying varied. As the washing processes proceed, the amount of microplastics gradually decreased. The minimum length (>40 µm) of micro-plastics generated were in plain-woven fabric. These results will be helpful to mitigate microplastics in the production of textiles and in selecting built-in filters, and focusing on the strict control of other parameters will be useful for the development of textile-based filters, such as washing bags.
With the increasing production of synthetic materials, more microplastic fibers are being generated while washing clothes. Consequently, these particles are increasingly detected in the aquatic environment. Synthetic fibers produced via washing have a relatively high contribution to microplastic pollution. Hence, recent research on reducing the release of microplastic fibers is attracting considerable attention. In this study, fabric-specific analysis was performed by strictly controlling various factors, and each washing and drying process was improved by focusing on the mechanical factors affecting microplastic release. Furthermore, the mass of the collected microplastic fibers and their length distribution were measured. Fabric construction, including chemical composition and yarn type, impacted the microplastics released during washing and drying. Differences in the mechanical factors during washing helped to identify the physical factors affecting microplastic release. These results on the release of microplastics may provide a basis for developing a filter system that can minimize the unintended environmental consequences.
Synthetic fibers released during washing are the primary source of microplastic pollution. Hence, research on reducing the release of microplastic fibers during washing has recently attracted considerable attention. As a result of previous studies, there is a difference in the amount of microplastic emission according to various types of fabrics. To mitigate the release of microplastics, the study of the reason for the difference in the amount of microplastics is needed. Therefore, this study investigated different synthetic fabrics that release microplastics and the physical properties of the fabrics that affect the release of fibers. Three types of fabrics with different chemical compositions were analyzed. The washing and drying processes were improved by focusing on the mechanical factors that affected microplastic release. Furthermore, based on the mass of the collected microplastic fibers, it was found that the chemical compositions of the fabric can affect the microplastics released during washing and drying. This evaluation of physical properties helped to identify the physical factors that affect microplastic release. These results may provide a basis for reducing microplastic fiber types, thereby minimizing unintended environmental pollution.
6 April 2022 in Journal of Science: Advanced Materials and Devices
Waterborne polyurethane-acrylate (WPUA) grafted with polyurethane was prepared to improve the film-forming ability of hard-type acrylic latex. To balance the film-formation ability and hardness, the WPUA latex was designed with a hard core (polyacrylate) and soft shell (polyurethane). The grafting ratio was controlled through varying the content of 2-hydroxyethyl methacrylate (HEMA) used to cap the ends of the polyurethane prepolymer. The morphologies of the latex particles, film surface, and fracture surface of the film were characterized through transmission electron microscopy, atomic force microscopy, and scanning electron microscopy, respectively. An increase in the grafting ratio resulted in the enhanced miscibility of polyurethane and polyacrylate but reduced adhesion between particles and increased minimum film formation temperature. In addition, grafting was essential to obtain transparent WPUA films. Excessive grafting induced defects such as micropores within the film, leading to the decreased hardness and adhesive strength of the film. The optimal HEMA content for the preparation of a WPUA coating with excellent film-forming ability and high hardness in ambient conditions was noted to be 50%. The final WPUA film was prepared without coalescence agents that generate volatile organic compounds.