During the global spread of COVID‐19, high demand and limited availability of melt‐blown filtration material led to a manufacturing backlog of N95 Filtering Facepiece Respirators (FFRs). This shortfall prompted the search for alternative filter materials that could be quickly mass produced while meeting N95 FFR filtration and breathability performance standards. Here, an unsupported, nonwoven layer of uncharged polystyrene (PS) microfibers was produced via electrospinning that achieves N95 performance standards based on physical parameters (e.g., filter thickness) alone. PS microfibers 3–6 μm in diameter and deposited in an ~5 mm thick filter layer are favorable for use in FFRs, achieving high filtration efficiencies (≥97.5%) and low pressure drops (≤15 mm H2O). The PS microfiber filter demonstrates durability upon disinfection with hydroxyl radicals (•OH), maintaining high filtration efficiencies and low pressure drops over six rounds of disinfection. Additionally, the PS microfibers exhibit antibacterial activity (1‐log removal of
- Award ID(s):
- 2040464
- PAR ID:
- 10274107
- Date Published:
- Journal Name:
- Environmental Science: Nano
- Volume:
- 8
- Issue:
- 3
- ISSN:
- 2051-8153
- Page Range / eLocation ID:
- 711 to 722
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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