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Ju J, Hayward RC. Interconnected Nanoporous Polysulfone by the Self-Assembly of Randomly Linked Copolymer Networks and Linear Multiblocks. ACS APPLIED MATERIALS & INTERFACES 2024; 16:34079-34088. [PMID: 38889392 DOI: 10.1021/acsami.4c05207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Porous materials have attracted considerable attention due to their versatile applications, especially in water purification. Interconnected nanoporous structures are distinguished by their high degree of porosity and resistance to clogging, as well as their insensitivity to nanostructural orientation. Previous works on randomly linked copolymer systems have shown that they can effectively produce disordered cocontinuous nanostructures, which upon removal of one component yield interconnected nanoporous materials. However, the cocontinuous nanomaterials previously developed using polystyrene (PS) and poly(d,l-lactic acid) (PLA) strands, and the resulting interconnected nanoporous PS monoliths, were far too brittle to enable practical use as membranes. Here, we study the self-assembly of randomly linked copolymer networks prepared using blocks of the engineering polymer polysulfone (PSU). A wide cocontinuous regime (spanning 40 wt %) was found for randomly end-linked copolymer networks (RECNs) constructed from PSU and PLA strands, via a combination of mechanical testing, gravimetry, small-angle X-ray scattering, and scanning electron microscopy. The PSU/PLA cocontinuous nanomaterial with symmetric composition showed 2.4 times higher Young's modulus and ∼100 times greater toughness than the corresponding PS/PLA sample. The interconnected nanoporous PSU fabricated after etching of PLA even exhibited 1.6 times greater toughness than PS/PLA prior to PLA removal. To facilitate the production of thin films of cocontinuous nanomaterials, we applied solution-processable randomly linked linear PSU/PLA multiblock polymers onto ultrafiltration membranes. The interconnected nanoporous PSU thin film generated by etching PLA was found to effectively reject 50 nm diameter particles without significantly compromising permeability. This discovery presents a valuable addition to the existing techniques used to fabricate PSU membranes. In contrast to traditional methods, which are sensitive to processing conditions, produce a wide range of pore sizes, and offer limited adjustability of pore size, the current technique is anticipated to enable interconnected PSU membranes with more uniform and tailorable porosity.
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Affiliation(s)
- Jaechul Ju
- Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Ryan C Hayward
- Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
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2
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Lee K, Corrigan N, Boyer C. Polymerization Induced Microphase Separation for the Fabrication of Nanostructured Materials. Angew Chem Int Ed Engl 2023; 62:e202307329. [PMID: 37429822 DOI: 10.1002/anie.202307329] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 06/30/2023] [Accepted: 07/10/2023] [Indexed: 07/12/2023]
Abstract
Polymerization induced microphase separation (PIMS) is a strategy used to develop unique nanostructures with highly useful morphologies through the microphase separation of emergent block copolymers during polymerization. In this process, nanostructures are formed with at least two chemically independent domains, where at least one domain is composed of a robust crosslinked polymer. Crucially, this synthetically simple method is readily used to develop nanostructured materials with the highly coveted co-continuous morphology, which can also be converted into mesoporous materials by selective etching of one domain. As PIMS exploits a block copolymer microphase separation mechanism, the size of each domain can be tightly controlled by modifying the size of block copolymer precursors, thus providing unparalleled control over nanostructure and resultant mesopore sizes. Since its inception 11 years ago, PIMS has been used to develop a vast inventory of advanced materials for an extensive range of applications including biomedical devices, ion exchange membranes, lithium-ion batteries, catalysis, 3D printing, and fluorescence-based sensors, among many others. In this review, we provide a comprehensive overview of the PIMS process, summarize latest developments in PIMS chemistry, and discuss its utility in a wide variety of relevant applications.
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Affiliation(s)
- Kenny Lee
- Cluster for Advanced Macromolecular Design (CAMD), School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
| | - Nathaniel Corrigan
- Cluster for Advanced Macromolecular Design (CAMD), School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
- Australian Centre for NanoMedicine (ACN), School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
| | - Cyrille Boyer
- Cluster for Advanced Macromolecular Design (CAMD), School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
- Australian Centre for NanoMedicine (ACN), School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
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3
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Ju J, Hayward RC. Cocontinuous Nanostructures by Microphase Separation of Statistically Cross-Linked Polystyrene/Poly(2-vinylpyridine) Networks. ACS APPLIED MATERIALS & INTERFACES 2023; 15:49633-49641. [PMID: 37843430 DOI: 10.1021/acsami.3c10985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
Cocontinuous polymeric nanostructures have drawn considerable attention due to their ability to combine distinct, percolation-dependent properties of two different polymer domains. Randomly end-linked copolymer networks (RECNs) have previously been shown to support the formation of disordered cocontinuous nanostructures across wide composition windows in a robust way. However, achieving highly efficient linking of telechelic polymers with excellent end-group fidelity often requires complex synthetic routes. As an alternative, we study here statistically cross-linked copolymer networks (SCCNs) composed of polystyrene and poly(2-vinylpyridine) (PS and P2VP) with cross-linkable allyl pendent groups that are conveniently synthesized by controlled radical copolymerization. Via selective extraction of P2VP, coupled with gravimetry, small-angle X-ray scattering, and electron microscopy, we find disordered cocontinuous phases across wide composition ranges (up to ≈ 35 wt %), approaching values previously determined for RECNs. Remarkably, even for samples that appear to exhibit full percolation, a substantial fraction of P2VP (≈ 20-30 wt %) cannot be removed, which we ascribe to short strands between nearby cross-linkers that are physically embedded within PS domains. The resulting PS porous monoliths with residual surface P2VP layers enable facile surface modification to resist protein adsorption and templating of porous gold nanostructures.
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Affiliation(s)
- Jaechul Ju
- Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Ryan C Hayward
- Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
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Le ML, Grzetic DJ, Delaney KT, Yang KC, Xie S, Fredrickson GH, Chabinyc ML, Segalman RA. Electrostatic Interactions Control the Nanostructure of Conjugated Polyelectrolyte–Polymeric Ionic Liquid Blends. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- My Linh Le
- Materials Department, University of California, Santa Barbara, California 93106, United States
| | - Douglas J. Grzetic
- Chemical Engineering Department, University of California, Santa Barbara, California 93106, United States
| | - Kris T. Delaney
- Chemical Engineering Department, University of California, Santa Barbara, California 93106, United States
| | - Kai-Chieh Yang
- Chemical Engineering Department, University of California, Santa Barbara, California 93106, United States
| | - Shuyi Xie
- Chemical Engineering Department, University of California, Santa Barbara, California 93106, United States
| | - Glenn H. Fredrickson
- Materials Department, University of California, Santa Barbara, California 93106, United States
- Chemical Engineering Department, University of California, Santa Barbara, California 93106, United States
| | - Michael L. Chabinyc
- Materials Department, University of California, Santa Barbara, California 93106, United States
| | - Rachel A. Segalman
- Materials Department, University of California, Santa Barbara, California 93106, United States
- Chemical Engineering Department, University of California, Santa Barbara, California 93106, United States
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Nano- to macro-scale control of 3D printed materials via polymerization induced microphase separation. Nat Commun 2022; 13:3577. [PMID: 35732624 PMCID: PMC9217958 DOI: 10.1038/s41467-022-31095-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 06/02/2022] [Indexed: 11/09/2022] Open
Abstract
Although 3D printing allows the macroscopic structure of objects to be easily controlled, controlling the nanostructure of 3D printed materials has rarely been reported. Herein, we report an efficient and versatile process for fabricating 3D printed materials with controlled nanoscale structural features. This approach uses resins containing macromolecular chain transfer agents (macroCTAs) which microphase separate during the photoinduced 3D printing process to form nanostructured materials. By varying the chain length of the macroCTA, we demonstrate a high level of control over the microphase separation behavior, resulting in materials with controllable nanoscale sizes and morphologies. Importantly, the bulk mechanical properties of 3D printed objects are correlated with their morphologies; transitioning from discrete globular to interpenetrating domains results in a marked improvement in mechanical performance, which is ascribed to the increased interfacial interaction between soft and hard domains. Overall, the findings of this work enable the simplified production of materials with tightly controllable nanostructures for broad potential applications.
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Park J, Easterling CP, Armstrong CC, Huber DL, Bowman JI, Sumerlin BS, Winey KI, Taylor MK. Nanoscale layers of precise ion-containing polyamides with lithiated phenyl sulfonate in the polymer backbone. Polym Chem 2022. [DOI: 10.1039/d2py00802e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Precise polyamide ionomer produces well-defined nanoscale layers.
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Affiliation(s)
- Jinseok Park
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Charles P. Easterling
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - Christopher C. Armstrong
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - Dale L. Huber
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - Jared I. Bowman
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA
| | - Brent S. Sumerlin
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA
| | - Karen I. Winey
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Mercedes K. Taylor
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
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Xu H, Xiao H, Ellison CJ, Mahanthappa MK. Flexible Nanoporous Materials by Matrix Removal from Cylinder-Forming Diblock Copolymers. NANO LETTERS 2021; 21:7587-7594. [PMID: 34460249 DOI: 10.1021/acs.nanolett.1c02097] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We describe a straightforward self-assembly route to nanoporous materials derived from a hexagonally-packed cylinder (HEX) morphology of a polyisoprene-block-polylactide (PI-b-PLA) diblock copolymer, by thermal cross-linking of the minority PI domains followed by selective chemical etching of the PLA matrix. The resulting mechanically stable and porous samples defy the expectation that the remaining cylinders cannot yield a robust, integrated material upon matrix removal. Scanning electron microscopy imaging reveals that this unexpected structural integrity stems from the interconnected nanofibrils therein, reflecting topological defects at the grain boundaries of the parent polydomain HEX nanostructure. Hydrodynamic radius-dependent poly(ethylene oxide) (Mn = 0.4-35 kg/mol) permeation behavior through these monoliths directly demonstrated the continuity and size selectivity of the nanoporous material. The ready accessibility of block copolymer HEX morphologies of varied chemistries suggests that this matrix etching strategy will enable the future design of functional, size-selective nanofiltration membrane materials.
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Affiliation(s)
- Hongyun Xu
- Department of Chemical Engineering & Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Han Xiao
- Department of Chemical Engineering & Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Christopher J Ellison
- Department of Chemical Engineering & Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Mahesh K Mahanthappa
- Department of Chemical Engineering & Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Lee J, Seo M. Downsizing of Block Polymer-Templated Nanopores to One Nanometer via Hyper-Cross-Linking of High χ-Low N Precursors. ACS NANO 2021; 15:9154-9166. [PMID: 33950684 DOI: 10.1021/acsnano.1c02690] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Synthesizing nanoporous polymer from the block polymer template by selective removal of the sacrificial domain offers straightforward pore size control as a function of the degree of polymerization (N). Downscaling pore size into the microporous regime (<2 nm) has been thermodynamically challenging, because the low N drives the system to disorder and the small-sized pore is prone to collapse. Herein, we report that maximizing cross-linking density of a block polymer precursor with an increased interaction parameter (χ) can help successfully stabilize the structure bearing pore sizes of 1.1 nm. We adopt polymerization-induced microphase separation (PIMS) combined with hyper-cross-linking as a strategy for the preparation of the bicontinuous block polymer precursors with a densely cross-linked framework by copolymerization of vinylbenzyl chloride with divinylbenzene and also Friedel-Crafts alkylation. Incorporating 4-vinylbiphenyl as a higher-χ comonomer to the sacrificial polylactide (PLA) block and optimizing the segregation strength versus cross-linking density allow for further downscaling. Control of pore size by N of PLA is demonstrated in the range of 9.9-1.1 nm. Accessible surface area to fluorescein-tagged dextrans is regulated by the relative size of the pore to the guest, and pore size is controlled. These findings will be useful for designing microporous polymers with tailored pore size for advanced catalytic and separation applications.
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Affiliation(s)
| | - Myungeun Seo
- Department of Chemistry, KAIST, Daejeon 34141, Korea
- KAIST Institute for Nanocentury, KAIST, Daejeon 34141, Korea
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Li M, Zhou L, Zhang Z, Wang Q, Gao J, Zhang S, Lei L. One-step synthesis of poly(methacrylate)- b-polyester via “one organocatalyst, two polymerizations”. Polym Chem 2021. [DOI: 10.1039/d1py00892g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In a “one organocatalyst, two polymerizations” system, triarylsulfonium hexafluorophosphate salt could spontaneously catalyze photo-ATRP and ROP. A well-defined PTMC-b-PMMA block copolymer was successfully synthesized in one-step.
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Affiliation(s)
- Mengmeng Li
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Lin Zhou
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Ziqi Zhang
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Qi Wang
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Jiani Gao
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Shiping Zhang
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
| | - Lin Lei
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China
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Zhang B, Xie S, Lodge TP, Bates FS. Phase Behavior of Diblock Copolymer–Homopolymer Ternary Blends with a Compositionally Asymmetric Diblock Copolymer. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Bo Zhang
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Shuyi Xie
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Timothy P. Lodge
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Frank S. Bates
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Hampu N, Werber JR, Chan WY, Feinberg EC, Hillmyer MA. Next-Generation Ultrafiltration Membranes Enabled by Block Polymers. ACS NANO 2020; 14:16446-16471. [PMID: 33315381 DOI: 10.1021/acsnano.0c07883] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Reliable and equitable access to safe drinking water is a major and growing challenge worldwide. Membrane separations represent one of the most promising strategies for the energy-efficient purification of potential water sources. In particular, porous membranes are used for the ultrafiltration (UF) of water to remove contaminants with nanometric sizes. However, despite exhibiting excellent water permeability and solution processability, existing UF membranes contain a broad distribution of pore sizes that limit their size selectivity. To maximize the potential utility of UF membranes and allow for precise separations, improvements in the size selectivity of these systems must be achieved. Block polymers represent a potentially transformative solution, as these materials self-assemble into well-defined domains of uniform size. Several different strategies have been reported for integrating block polymers into UF membranes, and each strategy has its own set of materials and processing considerations to ensure that uniform and continuous pores are generated. This Review aims to summarize and critically analyze the chemistries, processing techniques, and properties required for the most common methods for producing porous membranes from block polymers, with a particular focus on the fundamental mechanisms underlying block polymer self-assembly and pore formation. Critical structure-property-performance metrics will be analyzed for block polymer UF membranes to understand how these membranes compare to commercial UF membranes and to identify key research areas for continued improvements. This Review is intended to inform readers of the capabilities and current challenges of block polymer UF membranes, while stimulating critical thought on strategies to advance these technologies.
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Affiliation(s)
- Nicholas Hampu
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jay R Werber
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Wui Yarn Chan
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Elizabeth C Feinberg
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Marc A Hillmyer
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Hampu N, Werber JR, Hillmyer MA. Co-Casting Highly Selective Dual-Layer Membranes with Disordered Block Polymer Selective Layers. ACS APPLIED MATERIALS & INTERFACES 2020; 12:45351-45362. [PMID: 32986409 DOI: 10.1021/acsami.0c13726] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Highly selective and water permeable dual-layer ultrafiltration (UF) membranes comprising a disordered poly(methyl methacrylate-stat-styrene)-block-poly(lactide) selective layer and a polysulfone (PSF) support layer were fabricated using a co-casting technique. A dilute solution of diblock polymer was spin coated onto a solvent-swollen PSF layer, rapidly heated to dry and disorder the block polymer layer, and subsequently immersed into an ice water coagulation bath to kinetically trap the disordered state in the block polymer selective layer and precipitate the support layer by nonsolvent-induced phase separation. Subsequent removal of the polylactide block generated porous membranes suitable for UF. The permeability of these dual-layer membranes was modulated by tuning the concentration of the PSF casting solution, while the size-selectivity was maintained because of the narrow pore size distribution of the self-assembled block polymer selective layer. Elimination of the thermal annealing step resulted in a dramatic increase in the water permeability without adversely impacting the size-selectivity, as the disordered nanostructure present in the concentrated casting solution was kinetically trapped upon rapid drying. The co-casting strategy outlined in this work may enable the scalable fabrication of block polymer membranes with both high permeability and high selectivity.
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Affiliation(s)
- Nicholas Hampu
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jay R Werber
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Marc A Hillmyer
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Hampu N, Hillmyer MA. Nanostructural Rearrangement of Lamellar Block Polymers Cured in the Vicinity of the Order–Disorder Transition. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicholas Hampu
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Marc A. Hillmyer
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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