Surface engineering of intrinsically microporous poly(ether-ether-ketone) membranes: From flat to honeycomb structures
KAUST DepartmentAdvanced Membranes and Porous Materials Center, Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
Physical Science and Engineering (PSE) Division
Chemical Engineering Program
Advanced Membranes and Porous Materials Research Center
Embargo End Date2022-12-25
Permanent link to this recordhttp://hdl.handle.net/10754/666692
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AbstractSurface engineering of polymeric membranes can induce subtle changes in membrane properties and enhance their performance. Numerous membrane surface modification methods have been developed to improve the material performance. However, these methods can be complex, thus limiting their practical applications. Herein, we present a simple method for fabricating membranes with honeycomb surfaces by controlling the polymer molecular weight (Mw). Spirobisindane-based intrinsically microporous poly(ether-ether-ketone) (iPEEK-SBI) homopolymers with low and high Mws were synthesized and used to prepare organic solvent nanofiltration (OSN) membranes. The significant effects of polymer Mw on its physical properties, membrane morphology, and OSN performance were systematically investigated. iPEEK showed excellent solution processability, high Brunauer–Emmett–Teller surface area, and remarkable thermal stability. Three mechanically flexible OSN membranes exhibiting honeycomb surfaces with different honeycomb cell sizes were prepared using iPEEK-SBI homopolymers with low Mws at concentrations of 27–39 wt% in N-methyl-2-pyrrolidone. By contrast, the use of iPEEK-SBI homopolymers with high Mws yielded membranes with flat surfaces. The Mw cutoffs of the membranes were fine-tuned in the range of 408–772 g mol−1 by adjusting the dope solution concentration. Although the Mw cutoffs were unaffected by polymer Mw, the membranes derived from the polymer with low Mw exhibited substantially higher solvent permeance (18%–26%) than that of the high Mw membrane prepared at the same dope solution concentration. Stable performance was demonstrated over seven days of continuous cross-flow filtration and a six-month aging of the membranes. This work shows the importance of surface engineering for OSN membranes by adjusting polymer Mw. These findings open a new avenue for fine-tuning the properties of OSN membranes.
CitationAbdulhamid, M. A., Park, S.-H., Zhou, Z., Ladner, D. A., & Szekely, G. (2021). Surface engineering of intrinsically microporous poly(ether-ether-ketone) membranes: From flat to honeycomb structures. Journal of Membrane Science, 621, 118997. doi:10.1016/j.memsci.2020.118997
SponsorsThe research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST). The graphical abstract and Fig. 2 were created by Heno Hwang, scientific illustrator at KAUST. Zuo and David acknowledge partial funding from the US National Science Foundation, project #1534304, and computational support from the Palmetto Cluster, Clemson University's primary high-performance computing resource. The authors acknowledge SARS-CoV-2 for lab closure to allow the six-month aging study of the membranes.
JournalJournal of Membrane Science