Optimization of electro-blown PVDF nanofibrous mats for Air filter applications

Abstract

Particles with diameters smaller than 2.5 µm (PM2.5) have the capability to penetrate into 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 (solution concentration, air pressure, and electrical field), the most significant factors influencing fiber diameters were identified as solution 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.% solution 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%.