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Bioinspired membranes offer an alternative approach to improving the fouling resistance of commercial membranes for oil separations. Here, two perfluoropolyether oils, a lower viscosity Krytox 103 (K103) and a higher viscosity Krytox 107 (K107), were infused into commercial polyvinylidene fluoride (PVDF) ultrafiltration membranes to mimic the Nepenthes pitcher plant. The transmembrane pressure required to perform long-term oil permeance tests was optimized by testing the liquid-infused membranes at different applied pressures. Crystal violet staining and variable pressure scanning electron microscopy qualitatively suggest that the oil layer remained on the membranes after the oil separation experiments were conducted. Over 5 cycles, K103- and K107- liquid-infused membranes exhibited a consistent permeance of ∼ 30000 L m-2h−1 bar−1 at 1.0 bar and ∼ 14500 L m-2h−1 bar−1 at 0.5 bar, respectively. The steady performance further supports a long-lasting oil layer persists on the membrane surface and inside membrane’s pores. Next, experiments were conducted to determine the stability of the Krytox oil post accelerated cleaning tests using bleach. No structural changes to the Krytox oils were detected by thermogravimetric analysis or nuclear magnetic resonance spectroscopy. Dynamic fouling experiments using Escherichia coli K12 revealed that the liquid-infused membranes had higher flux recovery ratios (∼95 %) than the bare PVDF control membranes (∼55 %). Our results demonstrate that liquid-infused membranes exhibit chlorine stability and superior fouling resistance, presenting a promising bioinspired membrane that can be used in pressure-driven oil separation applications.
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This content will become publicly available on May 14, 2026
Slippery Liquid-Infused Porous Surfaces Infused with Thermotropic Liquid Crystals Enable Droplet-Based, Naked-Eye Reporting of Changes in Peptide Structure and Protease Activity
- Award ID(s):
- 2309000
- PAR ID:
- 10637884
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 17
- Issue:
- 19
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 27882 to 27894
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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