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Title: Grafting polysiloxane onto ultrafiltration membranes to optimize surface energy and mitigate fouling
Conventional approaches to mitigate fouling of membrane surfaces impart hydrophilicity to the membrane surface, which increases the water of hydration and fluidity near the surface. By contrast, we demonstrate here that tuning the membrane surface energy close to that of the dispersive component of water surface tension (21.8 mN m −1 ) can also improve the antifouling properties of the membrane. Specifically, ultrafiltration (UF) membranes were first modified using polydopamine (PDA) followed by grafting of amine-terminated polysiloxane (PSi-NH 2 ). For example, with 2 g L −1 PSi-NH 2 coating solution, the obtained coating layer contains 53% by mass fraction PSi-NH 2 and exhibits a total surface energy of 21 mN m −1 , decreasing the adsorption of bovine serum albumin by 44% compared to the unmodified membrane. When challenged with 1 g L −1 sodium alginate in a constant-flux crossflow system, the PSi-NH 2 -grafted membrane exhibits a 70% lower fouling rate than the pristine membrane at a water flux of 110 L (m 2 h) −1 and good stability when cleaned with NaOH solutions.  more » « less
Award ID(s):
1635026
PAR ID:
10205461
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Soft Matter
Volume:
16
Issue:
21
ISSN:
1744-683X
Page Range / eLocation ID:
5044 to 5053
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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