Dual-phase microporous polymer nanofilms by interfacial polymerization for ultrafast molecular separation
Abstract
Fine-tuning microporosity in polymers with a scalable method has great potential for energy-efficient molecular separations. Here, we report a dual-phase molecular engineering approach to prepare microporous polymer nanofilms through interfacial polymerization. By integrating two micropore-generating units such as a water-soluble Tröger’s base diamine (TBD) and a contorted spirobifluorene (SBF) motif, the resultant TBD-SBF polyamide shows an unprecedentedly high surface area. An ultrathin TBD-SBF membrane (~20 nm) exhibits up to 220 times improved solvent permeance with a moderate molecular weight cutoff (~640 g mol-1) compared to the control membrane prepared by conventional chemistry, which outperforms currently reported polymeric membranes. We also highlight the great potential of the SBF-based microporous polyamides for hydrocarbon separations by exploring the isomeric effects of aqueous phase monomers to manipulate microporosity.
Funding: This work was supported by ExxonMobil through the MIT Energy Initiative. I.P. acknowledges support from the King Abdullah University of Science and Technology (BAS/1/1323/01-01). Author contributions: All authors contributed to the scientific discussion and manuscript preparation. Z.P.S. contributed to conceptualization, supervision, and funding acquisition. T.H.L. led the experimental design, data curation, and writing of the original manuscript. W.-N.W. performed the synthesis and characterization of monomers. I.P. and M.B. carried out the molecular simulations. Competing interests: The authors declare that they have no competing interests. Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials.