This content will become publicly available on August 9, 2023
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- Polymer Chemistry
- Page Range or eLocation-ID:
- 4547 to 4556
- Sponsoring Org:
- National Science Foundation
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The combination of precision control with wide tunability remains a challenge for the fabrication of porous nanomaterials suitable for studies of nanostructure–behavior relationships. Polymer micelle templates broadly enable porous materials, however micelle equilibration hampers independent pore and wall size control. Persistent micelle templates (PMT) have emerged as a kinetic controlled platform that uniquely decouples the control of pore and wall dimensions. Here, chain exchange is inhibited to preserve a constant template dimension (pore size) despite the shifting equilibrium while materials are added between micelles. Early PMT demonstrations were synthesis intensive with limited 1–1.3× pore size tuning for a given polymer. Here we demonstrate PMT swelling with homopolymer enables 1–3.2× (13.3–41.9 nm) pore size variation while maintaining a monomodal distribution with up to 250 wt% homopolymer, considerably higher than the ∼90 wt% limit found for equilibrating micelles. These swollen PMTs enabled nanomaterial series with constant pore size and precision varied wall-thickness. Kinetic size control here is unexpected since the homopolymer undergoes dynamic exchange between micelles. The solvent selection influenced the time window before homopolymer phase separation, highlighting the importance of considering homopolymer–solvent interactions. This is the first PMT demonstration with wide variation of both the pore and wall dimensions using amore »
The cellular glycocalyx and extracellular matrix are rich in glycoproteins and proteoglycans that play essential physical and biochemical roles in all life. Synthetic mimics of these natural bottlebrush polymers have wide applications in biomedicine, yet preparation has been challenged by their high grafting and glycosylation densities. Using one-pot dual-catalysis polymerization of glycan-bearing α-amino acid
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Extraction and reconstitution of membrane proteins into lipid nanodiscs encased by zwitterionic styrene-maleic amide copolymers
Membrane proteins can be reconstituted in polymer-encased nanodiscs for studies under near-physiological conditions and in the absence of detergents, but traditional styrene-maleic acid copolymers used for this purpose suffer severely from buffer incompatibilities. We have recently introduced zwitterionic styrene-maleic amide copolymers (zSMAs) to overcome this limitation. Here, we compared the extraction and reconstitution of membrane proteins into lipid nanodiscs by a series of zSMAs with different styrene:maleic amide molar ratios, chain sizes, and molecular weight distributions. These copolymers solubilize, stabilize, and support membrane proteins in nanodiscs with different efficiencies depending on both the structure of the copolymers and the membrane proteins.
Installation of synergistic binding sites onto porous organic polymers for efficient removal of perfluorooctanoic acid
Herein, we report a strategy to construct highly efficient perfluorooctanoic acid (PFOA) adsorbents by installing synergistic electrostatic/hydrophobic sites onto porous organic polymers (POPs). The constructed model material of PAF-1-NDMB (NDMB = N,N-dimethyl-butylamine) demonstrates an exceptionally high PFOA uptake capacity over 2000 mg g−1, which is 14.8 times enhancement compared with its parent material of PAF-1. And it is 32.0 and 24.1 times higher than benchmark materials of DFB-CDP (β-cyclodextrin (β-CD)-based polymer network) and activated carbon under the same conditions. Furthermore, PAF-1-NDMB exhibits the highest
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