In this study, pure polyvinylidene fluoride (PVDF), pure thermoplastic polyurethane (TPU), and PVDF/TPU blend nanofibers (1:3, 2:2, 3:1 ratios) were produced via electrically assisted solution blow spinning for air filtration applications. Scanning electron microscopy (SEM) analysis was conducted to investigate the diameters and morphology of nanofibers. The filtration performance of nanofibrous mats was examined by air filtration test with challenging with 0.26 ± 0.07 μm salt particles. Moreover, the flexibility and strength of the samples were determined via tensile tests. Results showed that pure TPU nanofibers had better mechanical properties, while pure PVDF nanofibers showed better filtration performance. However, 3PVDF/1TPU nanofibrous sample had high filtration efficiency (98.86%) close to pure PVDF (99.85%) and better flexibility (32.80% elongation) compared to pure PVDF (11.64% elongation).
Particles with diameters smaller than 2.5 µm (PM2.5) have the capability to penetrate respiratory system, thereby exerting adverse effects on human health. High-efficiency nanofiber mats present a viable and efficient solution for the purification of ambient air contaminated with such particulate matter. In this study, PVDF based electret nanofiber mats were optimized via electro-blowing technique. The experimental parameters were systematically devised utilizing a Taguchi three-level L9 orthogonal design, and the results were subsequently analyzed using ANOVA. In this context, among the examined parameters (concentration, air pressure, and electrical field), the most significant factors influencing fiber diameters were identified as concentration and electric field strength. While an increase in air pressure exhibited a negligible influence on fiber diameters, it was observed to mitigate undesired droplet density. The optimal parameters yielding the thinnest fiber (124 ± 71 nm) were determined as 9 wt.% concentration, 2 bar air pressure, and 30 kV electrical voltage. Furthermore, the application of corona discharge treatment to the specimens resulted in a remarkable enhancement of quality factors by over 70%.
Air pollution is a significant global health concern, causing respiratory diseases, cardiovascular disorders, and various cancers. The increasing population, industrial activities, fuel emissions, and construction activities contribute to the formation of particulate matter, leading to air pollution. The inhalation of fine particulate matter (PM2.5) and various toxic gases substantially exacerbates these health risks. Traditional air filtration systems, while relatively effective at capturing larger particles, fall short in capturing nanoscale pollutants. To address these deficiencies, nanofibrous air filters have emerged as a significant innovation. Due to their large surface area and high porosity, nanofibrous filters can effectively capture smaller particles and harmful gases. Research has demonstrated that nanofibrous filters exhibit high efficiency in filtering PM2.5 and smaller particles, as well as bacteria, and viruses. Furthermore, the long-term use of these filters presents a significant potential to reduce health risks associated with air pollution. This study emphasizes the critical importance of developing and implementing nanofibrous filter technology and the innovative research in this field to improve air quality and protect public health. The widespread adoption of this technology is viewed as an effective strategy to mitigate the adverse health effects of air pollution and create healthier living environments. In this context, the study presents insights into the current and future applications of nanofibrous air filters.