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Lu Q, Wang Z, Zhang S, Wang J, Mao X, Xie L, Liu Q, Zeng H. Molecular interaction mechanism for humic acids fouling resistance on charged, zwitterion-like and zwitterionic surfaces. J Colloid Interface Sci 2024; 666:393-402. [PMID: 38603881 DOI: 10.1016/j.jcis.2024.04.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/27/2024] [Accepted: 04/05/2024] [Indexed: 04/13/2024]
Abstract
Humic acids (HA) are ubiquitous in surface waters, leading to significant fouling challenges. While zwitterion-like and zwitterionic surfaces have emerged as promising candidates for antifouling, a quantitative understanding of molecular interaction mechanism, particularly at the nanoscale, still remains elusive. In this work, the intermolecular forces between HA and charged, zwitterion-like or zwitterionic monolayers in aqueous environments were quantified using atomic force microscope. Compared to cationic MTAC ([2-(methacryloyloxy)ethyl]trimethylammonium chloride), which exhibited an adhesion energy of ∼1.342 mJ/m2 with HA due to the synergistic effect of electrostatic attraction and possible cation-π interaction, anionic SPMA (3-sulfopropyl methacrylate) showed a weaker adhesion energy (∼0.258 mJ/m2) attributed to the electrostatic repulsion. Zwitterion-like MTAC/SPMA mixture, driven by electrostatic attraction between opposite charges, formed a hydration layer that prevented the interaction with HA, thereby considerably reducing adhesion energy to ∼0.123 mJ/m2. In contrast, zwitterionic MPC (2-methacryloyloxyethyl phosphorylcholine) and DMAPS ([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide) displayed ultralow adhesion energy (0.06-0.07 mJ/m2) with HA, arising from their strong dipole moments which could induce a tight hydration layer that effectively inhibited HA fouling. The pH-mediated electrostatic interaction resulted in the increased adhesion energy for MTAC but decreased adhesion energy for SPMA with elevated pH, while the adhesion energy for zwitterion-like and zwitterionic surfaces was independent of environmental pH. Density functional theory (DFT) simulation confirmed the strong binding capability of MPC and DMAPS with water molecules (∼-12 kcal mol-1). This work provides valuable insights into the molecular interaction mechanisms underlying humic-substance-fouling resistance of charged, zwitterion-like and zwitterionic materials at the nanoscale, shedding light on developing more effective strategy for HA antifouling in water treatment.
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Affiliation(s)
- Qiuyi Lu
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Zhoujie Wang
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, PR China
| | - Shishuang Zhang
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, PR China
| | - Jingyi Wang
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Xiaohui Mao
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Lei Xie
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, PR China.
| | - Qi Liu
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Hongbo Zeng
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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Song X, Man J, Qiu Y, Wang J, Liu J, Li R, Zhang Y, Li J, Li J, Chen Y. Design, preparation, and characterization of lubricating polymer brushes for biomedical applications. Acta Biomater 2024; 175:76-105. [PMID: 38128641 DOI: 10.1016/j.actbio.2023.12.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/21/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023]
Abstract
The lubrication modification of biomedical devices significantly enhances the functionality of implanted interventional medical devices, thereby providing additional benefits for patients. Polymer brush coating provides a convenient and efficient method for surface modification while ensuring the preservation of the substrate's original properties. The current research has focused on a "trial and error" method to finding polymer brushes with superior lubricity qualities, which is time-consuming and expensive, as obtaining effective and long-lasting lubricity properties for polymer brushes is difficult. This review summarizes recent research advances in the biomedical field in the design, material selection, preparation, and characterization of lubricating and antifouling polymer brushes, which follow the polymer brush development process. This review begins by examining various approaches to polymer brush design, including molecular dynamics simulation and machine learning, from the fundamentals of polymer brush lubrication. Recent advancements in polymer brush design are then synthesized and potential avenues for future research are explored. Emphasis is placed on the burgeoning field of zwitterionic polymer brushes, and highlighting the broad prospects of supramolecular polymer brushes based on host-guest interactions in the field of self-repairing polymer brush applications. The review culminates by providing a summary of methodologies for characterizing the structural and functional attributes of polymer brushes. It is believed that a development approach for polymer brushes based on "design-material selection-preparation-characterization" can be created, easing the challenge of creating polymer brushes with high-performance lubricating qualities and enabling the on-demand creation of coatings. STATEMENT OF SIGNIFICANCE: Biomedical devices have severe lubrication modification needs, and surface lubrication modification by polymer brush coating is currently the most promising means. However, the design and preparation of polymer brushes often involves "iterative testing" to find polymer brushes with excellent lubrication properties, which is both time-consuming and expensive. This review proposes a polymer brush development process based on the "design-material selection-preparation-characterization" strategy and summarizes recent research advances and trends in the design, material selection, preparation, and characterization of polymer brushes. This review will help polymer brush researchers by alleviating the challenges of creating polymer brushes with high-performance lubricity and promises to enable the on-demand construction of polymer brush lubrication coatings.
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Affiliation(s)
- Xinzhong Song
- Key Laboratory of High Efficiency and Clean Mechanicalanufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, PR China; Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, PR China
| | - Jia Man
- Key Laboratory of High Efficiency and Clean Mechanicalanufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, PR China; Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, PR China.
| | - Yinghua Qiu
- Key Laboratory of High Efficiency and Clean Mechanicalanufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, PR China; Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, PR China
| | - Jiali Wang
- Qilu Hospital of Shandong University, Jinan 250012, PR China
| | - Jianing Liu
- Qilu Hospital of Shandong University, Jinan 250012, PR China
| | - Ruijian Li
- Qilu Hospital of Shandong University, Jinan 250012, PR China
| | - Yongqi Zhang
- Key Laboratory of High Efficiency and Clean Mechanicalanufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, PR China; Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, PR China
| | - Jianyong Li
- Key Laboratory of High Efficiency and Clean Mechanicalanufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, PR China; Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, PR China
| | - Jianfeng Li
- Key Laboratory of High Efficiency and Clean Mechanicalanufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, PR China; Key National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, PR China
| | - Yuguo Chen
- Qilu Hospital of Shandong University, Jinan 250012, PR China
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3
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Ishraaq R, Akash TS, Bera A, Das S. Hydrophilic and Apolar Hydration in Densely Grafted Cationic Brushes and Counterions with Large Mobilities. J Phys Chem B 2024; 128:381-392. [PMID: 38148252 DOI: 10.1021/acs.jpcb.3c07520] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
We employ an all-atom molecular dynamics (MD) simulation framework to unravel water microstructure and ion properties for cationic [poly(2-(methacryloyloxy)ethyl) trimethylammonium chloride] (PMETAC) brushes with chloride ions as counterions. First, we identify locally separate water domains (or first hydration shells) each around {N(CH3)3}+ and the C═O functional groups of the PMETAC chain and one around the Cl- ion. These first hydration shells around the respective moieties overlap, and the extent of the overlap depends on the nature of the species triggering it. Second, despite the overlap, the water molecules in these domains demonstrate disparate properties dictated by the properties of the atoms and groups around which they are located. For example, the presence of the methyl groups makes the {N(CH3)3}+ group trigger apolar hydration as evidenced by the corresponding orientation of the dipole of the water molecules around the {N(CH3)3}+ moiety. These water molecules around the {N(CH3)3}+ group also have enhanced tetrahedrality compared to the water molecules constituting the hydration layer around the C═O group and the Cl- counterion. Our simulations also identify that there is an intervening water layer between the Cl- ion and {N(CH3)3}+ group: this layer prevents the Cl- ion from coming very close to the {N(CH3)3}+ group. As a consequence, there is a significantly large mobility of the Cl- ions inside the PMETAC brush layer. Furthermore, the C═O group of the polyelectrolyte (PE) chain, due to the partial negative charge on the oxygen atom and the specific structure of the PMETAC brush system, demonstrates strongly hydrophilic behavior and enforces a specific dipole response of water molecules analogous to that experienced by water around anionic species of high charge density. In summary, our findings confirm that PMETAC brushes undergo hydrophilic hydration at one site and apolar hydration at another site and ensure large mobility of the supported Cl- counterions.
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Affiliation(s)
- Raashiq Ishraaq
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Tanmay Sarkar Akash
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Arka Bera
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Siddhartha Das
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, United States
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Kaur S, Tomar D, Chaudhary M, Rana B, Kaur H, Nigam V, Jena KC. Interfacial molecular structure of phosphazene-based polymer electrolyte at the air-aqueous interface using sum frequency generation vibrational spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 36:105001. [PMID: 37988750 DOI: 10.1088/1361-648x/ad0e94] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 11/21/2023] [Indexed: 11/23/2023]
Abstract
The change induced in the physicochemical properties of polymer while hosting ions provides a platform for studying its potential applications in electrochemical devices, water treatment plants, and materials engineering science. The ability to host ions is limited in very few polymers, which lack a detailed molecular-level understanding for showcasing the polymer-ion linkage behavior at the interfacial region. In the present manuscript, we have employed sum frequency generation (SFG) vibrational spectroscopy to investigate the interfacial structure of a new class phosphazene-based methoxyethoxyethoxyphosphazene (MEEP) polymer in the presence of lithium chloride salt at the air-aqueous interface. The interfacial aspects of the molecular system collected through SFG spectral signatures reveal enhanced water ordering and relative hydrogen bonding strength at the air-aqueous interface. The careful observation of the study finds a synchronous contribution of van der Waals and electrostatic forces in facilitating changes in the interfacial water structure that are susceptible to MEEP concentration in the presence of ions. The observation indicates that dilute MEEP concentrations support the role of electrostatic interaction, leading to an ordered water structure in proximity to diffused ions at the interfacial region. Conversely, higher MEEP concentrations promote the dominance of van der Waals interactions at the air-aqueous interface. Our study highlights the establishment of polymer electrolyte (PE) characteristics mediated by intermolecular interactions, as observed through the spectral signatures witnessed at the air-aqueous interface. The investigation illustrates the polymer-ion linkage adsorption effects at the interfacial region, which explains the macroscopic changes observed from the cyclic voltammetry studies. The fundamental findings from our studies can be helpful in the design and fine-tuning of better PE systems that can offer improved hydrophobic membranes and interface stability for use in electrochemical-based power sources.
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Affiliation(s)
- Sarabjeet Kaur
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
| | - Deepak Tomar
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
| | - Monika Chaudhary
- Department of Biomedical Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
| | - Bhawna Rana
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
| | - Harsharan Kaur
- Department of Biomedical Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
| | - Vineeta Nigam
- Defence Materials Stores Research and Development Establishment, Kanpur 208013, India
| | - Kailash C Jena
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
- Department of Biomedical Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India
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5
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Xu L, Hu Y, Zhao D, Zhang W, Wang H. A Versatile Assembly Approach toward Multifunctional Supramolecular Poly(Ionic Liquid) Nanoporous Membranes in Water. Macromol Rapid Commun 2023; 44:e2300189. [PMID: 37248809 DOI: 10.1002/marc.202300189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/25/2023] [Indexed: 05/31/2023]
Abstract
Hydrogen (H)-bonding-integration of multiple ingredients into supramolecular polyelectrolyte nanoporous membranes in water, thereby achieving tailor-made porous architectures, properties, and functionalities, remains one of the foremost challenges in materials chemistry due to the significantly opposing action of water molecules against H-bonding. Herein, a strategy is described that allows direct fusing of the functional attributes of small additives into water-involved hydrogen bonding assembled supramolecular poly(ionic liquid) (PIL) nanoporous membranes (SPILMs) under ambient conditions. It discloses that the pore size distributions and mechanical properties of SPILMs are rationally controlled by tuning the H-bonding interactions between small additives and homo-PIL. It demonstrates that, benefiting from the synergy of multiple noncovalent interactions, small dye additives/homo-PIL solutions can be utilized as versatile inks for yielding colorful light emitting films with robust underwater adhesion strength, excellent stretchability, and flexibility on diverse substrates, including both hydrophilic and hydrophobic surfaces. This system provides a general platform for integrating the functional attributes of a diverse variety of additives into SPILMs to create multifunctional and programmable materials in water.
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Affiliation(s)
- Luyao Xu
- Key Laboratory of Functional Polymer Materials of the Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, P. R. China
| | - Yingyi Hu
- Key Laboratory of Functional Polymer Materials of the Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, P. R. China
| | - Dongbing Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, P. R. China
| | - Wangqing Zhang
- Key Laboratory of Functional Polymer Materials of the Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, P. R. China
| | - Hong Wang
- Key Laboratory of Functional Polymer Materials of the Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, P. R. China
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6
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Huang Y, Zheng X, Ye S, Hua Z, Liu G. Counterion-Mediated Hydrogen Bonding Making Poly(styrenesulfonate)-Based Strong Polyelectrolytes pH-Responsive. J Am Chem Soc 2023; 145:20745-20748. [PMID: 37721441 DOI: 10.1021/jacs.3c05456] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
Owing to the well-established fact that poly(styrenesulfonate) (PSS)-based strong polyelectrolytes are pH insensitive, their applications in smart materials have thus been severely limited. However, we demonstrate here that counterion-mediated hydrogen bonding (CMHB) makes the PSS brush pH-responsive. With decreasing pH, more hydrogen bonds are formed between the bound hydronium counterions and the sulfonate (-SO3-) groups in the PSS brush. At the microscale, the formation of more hydrogen bonds with decreasing pH leads to a more ordered structure and a larger tilt angle of the -SO3- groups in the PSS brush. On the other hand, a range of important physicochemical properties of the PSS brush, including hydration, stiffness, wettability, and adhesion, are responsive to pH, induced by the effect of CMHB on the PSS brush. Our work reveals a clear structure-property relationship for the pH-responsive PSS brush. This work not only provides a new understanding of the fundamental properties of the PSS brush but also greatly extends the applications of PSS-based strong polyelectrolytes.
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Affiliation(s)
- Yue Huang
- Hefei National Research Center for Physical Science at the Microscale, Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, People's Republic of China 230026
| | - Xiaoxuan Zheng
- School of Emerging Technology, University of Science and Technology of China, Hefei, People's Republic of China 230026
| | - Shuji Ye
- Hefei National Research Center for Physical Science at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei, People's Republic of China 230026
- Hefei National Laboratory, University of Science and Technology of China, Hefei, People's Republic of China 230088
| | - Zan Hua
- The Key Laboratory of Functional Molecular Solids, Ministry of Education, and Department of Materials Chemistry, School of Chemistry and Materials Science, Anhui Normal University, Wuhu, People's Republic of China 214002
| | - Guangming Liu
- Hefei National Research Center for Physical Science at the Microscale, Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, People's Republic of China 230026
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7
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Guo W, Lu T, Crisci R, Nagao S, Wei T, Chen Z. Determination of protein conformation and orientation at buried solid/liquid interfaces. Chem Sci 2023; 14:2999-3009. [PMID: 36937592 PMCID: PMC10016606 DOI: 10.1039/d2sc06958j] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
Protein structures at solid/liquid interfaces mediate interfacial protein functions, which are important for many applications. It is difficult to probe interfacial protein structures at buried solid/liquid interfaces in situ at the molecular level. Here, a systematic methodology to determine protein molecular structures (orientation and conformation) at buried solid/liquid interfaces in situ was successfully developed with a combined approach using a nonlinear optical spectroscopic technique - sum frequency generation (SFG) vibrational spectroscopy, isotope labeling, spectra calculation, and computer simulation. With this approach, molecular structures of protein GB1 and its mutant (with two amino acids mutated) were investigated at the polymer/solution interface. Markedly different orientations and similar (but not identical) conformations of the wild-type protein GB1 and its mutant at the interface were detected, due to the varied molecular interfacial interactions. This systematic strategy is general and can be widely used to elucidate protein structures at buried interfaces in situ.
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Affiliation(s)
- Wen Guo
- Department of Chemistry, University of Michigan 930 North University Avenue Ann Arbor 48109 Michigan USA
| | - Tieyi Lu
- Department of Chemistry, University of Michigan 930 North University Avenue Ann Arbor 48109 Michigan USA
| | - Ralph Crisci
- Department of Chemistry, University of Michigan 930 North University Avenue Ann Arbor 48109 Michigan USA
| | - Satoshi Nagao
- Graduate School of Science, University of Hyogo 3-2-1 Koto, Ako-gun Kamigouri-cho Hyogo 678-1297 Japan
| | - Tao Wei
- Department of Chemical Engineering, Howard University 2366 Sixth Street NW Washington 20059 DC USA
| | - Zhan Chen
- Department of Chemistry, University of Michigan 930 North University Avenue Ann Arbor 48109 Michigan USA
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8
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Zhang J, Hua Z, Liu G. Effect of Counterion-Mediated Hydrogen Bonding on Polyelectrolytes at the Solid/Water Interface: Current Understanding and Perspectives. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:2881-2889. [PMID: 36780613 DOI: 10.1021/acs.langmuir.2c03470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The counterion-mediated hydrogen bonding (CMHB) effect can be generated in polyelectrolyte systems when hydrogen bonds are formed between the bound counterions and polyelectrolyte chains. This Perspective mainly discusses the effect of CMHB on polyelectrolytes at the solid/water interface. The CMHB effect generated by the hydroxide (OH-) or hydronium (H3O+) counterions gives rise to a pH responsiveness of strong polyelectrolyte brushes (SPBs) whose strength can be modulated by the external salt concentration. Further studies have shown that the CMHB effect on SPBs can be extended beyond the OH- and H3O+ counterions and that the CMHB effect can be observed in the systems of weak polyelectrolyte brushes (WPBs) and polyelectrolyte multilayers (PEMs). Based on the understanding of the mechanisms of the CMHB effect on polyelectrolytes at the solid/water interface, we have demonstrated that a range of important properties of SPBs, WPBs, and PEMs can be tuned by pH with the consideration of the CMHB effect. Future directions for the CMHB effect on polyelectrolytes are also discussed. The insights on the CMHB effect on polyelectrolytes at the solid/water interface would promote the development of smart interfacial polyelectrolyte materials in a wide range of fields.
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Affiliation(s)
- Jian Zhang
- Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, P. R. China
- Key Laboratory of Yarn Materials Forming and Composite Processing Technology of Zhejiang Province, College of Material and Textile Engineering, Jiaxing University, Jiaxing 314001, P. R. China
| | - Zan Hua
- Biomass Molecular Engineering Center and Department of Materials Science and Engineering, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei 230036, P. R. China
| | - Guangming Liu
- Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, P. R. China
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9
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Asokan-Sheeja H, Yang S, A Adones A, Chen W, B Fulton B, K Chintapula U, T Nguyen K, J Lovely C, A Brautigam C, Nam K, Dong H. Self‐assembling Peptides with Internal Ionizable Unnatural Amino Acids: A New and General Approach to pH‐responsive Peptide Materials. Chem Asian J 2022; 17:e202200724. [DOI: 10.1002/asia.202200724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/11/2022] [Indexed: 11/06/2022]
Affiliation(s)
| | - Su Yang
- The University of Texas at Arlington Chemistry UNITED STATES
| | - Ashley A Adones
- The University of Texas at Arlington Chemistry UNITED STATES
| | - Weike Chen
- The University of Texas at Arlington Chemistry UNITED STATES
| | | | | | - Kytai T Nguyen
- The University of Texas at Arlington Bioengineering UNITED STATES
| | - Carl J Lovely
- The University of Texas at Arlington Chemistry UNITED STATES
| | - Chad A Brautigam
- UT Southwestern: The University of Texas Southwestern Medical Center Biophysics UNITED STATES
| | - Kwangho Nam
- The University of Texas at Arlington Chemistry UNITED STATES
| | - He Dong
- University of Texas at Arlington Chemistry 700 Planetarium Place 76019 Arlington UNITED STATES
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10
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Yuan H, Liu G. Polyelectrolyte Complexation When Considering the Counterion-Mediated Hydrogen Bonding. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:8179-8186. [PMID: 35748635 DOI: 10.1021/acs.langmuir.2c01186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In this work, we have investigated a pH-modulated complexation between two oppositely charged strong polyelectrolytes to demonstrate the effect of counterion-mediated hydrogen bonding (CMHB) on polyelectrolyte complexation. We have found that such a pH-modulated complexation cannot be understood without considering the CMHB. Thermodynamically, the effect of CMHB on the polyelectrolyte complexation is manifested by the alteration of both enthalpic and entropic contributions to the free energy change. The pH-dependent intrinsic ion-pairing and complex coacervation processes of the polyelectrolyte complexation can be understood when considering the CMHB. Our study demonstrates that both the extent of polyelectrolyte complex formation in bulk solutions and the formation of polyelectrolyte multilayers on surfaces are controlled by the pH-dependent intrinsic ion-pairing process. Furthermore, on the basis of the pH-dependent intrinsic ion pairing, the properties of the multilayers can be tuned by pH. This work provides a new strategy to control the polyelectrolyte complexation with counterions and will inspire new ideas for building advanced polyelectrolyte materials.
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Affiliation(s)
- Haiyang Yuan
- Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, P. R. China 230026
| | - Guangming Liu
- Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, P. R. China 230026
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11
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Aktas Eken G, Ober CK. Strong Polyelectrolyte Brushes via Alternating Copolymers of Styrene and Maleimides: Synthesis, Properties, and Stability. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00647] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Gozde Aktas Eken
- Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Christopher K. Ober
- Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
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12
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Crystalline hydrogen bonding of water molecules confined in a metal-organic framework. Commun Chem 2022; 5:51. [PMID: 36697686 PMCID: PMC9814150 DOI: 10.1038/s42004-022-00666-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 03/10/2022] [Indexed: 01/28/2023] Open
Abstract
Hydrogen bonding (H-bonding) of water molecules confined in nanopores is of particular interest because it is expected to exhibit chemical features different from bulk water molecules due to their interaction with the wall lining the pores. Herein, we show a crystalline behavior of H-bonded water molecules residing in the nanocages of a paddlewheel metal-organic framework, providing in situ and ex situ synchrotron single-crystal X-ray diffraction and Raman spectroscopy studies. The crystalline H-bond is demonstrated by proving the vibrational chain connectivity arising between hydrogen bond and paddlewheel Cu-Cu bond in sequentially connected Cu-Cu·····coordinating H2O·····H-bonded H2O and by proving the spatial ordering of H-bonded water molecules at room temperature, where they are anticipated to be disordered. Additionally, we show a substantial distortion of the paddlewheel Cu2+-centers that arises with water coordination simultaneously. Also, we suggest the dynamic coordination bond character of the H-bond of the confined water, by which an H-bond transitions to a coordination-bond at the Cu2+-center instantaneously after dissociating a previously coordinated H2O.
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13
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Yu J, Chen C, Gilchrist JB, Buffet JC, Wu Z, Mo G, Xie F, O'Hare D. Aged layered double hydroxide nanosheet-polyvinyl alcohol dispersions for enhanced gas barrier coating performance. MATERIALS HORIZONS 2021; 8:2823-2833. [PMID: 34486636 DOI: 10.1039/d1mh00433f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Whilst applying a coating layer to a polymer film is a routine approach to enhance the gas barrier properties of the film, it is counter-intuitive to consider that the gas barrier performance of the film would improve by ageing the coating dispersion for weeks before application. Herein, we report that the oxygen barrier performance of a 12 μm PET film coated with a dispersion of inorganic nanosheets in polyvinyl alcohol can be significantly enhanced by ageing this coating dispersion for up to 8 weeks before application. We found up to a 37-fold decrease in the oxygen transmission rate (OTR) of the PET coated film using aged dispersions of [Mg0.66Al0.33(OH)2](NO3)0.33 layered double hydroxide nanosheets (Mg2Al-LDH NS) in polyvinyl alcohol (PVA) compared to the film coated with an equivalent freshly prepared LDH/PVA dispersion. A limiting OTR value of 0.31 cc m-2 day-1 was achieved using the PET film coated with a 3 week aged LDH NS/PVA dispersion. X-ray diffraction experiments show that the degree of in plane alignment of LDH NS on the PET film surface increased significantly from 70.6 ± 0.6 to 86.7 ± 0.6 (%) (100% represents complete alignment of LDH NS platelets on the film surface) for the 4 week aged dispersion compared to the freshly prepared layer. We postulate that when the Mg2Al-LDH NS are aged in PVA the coiled PVA aggregates start to unwrap and attach onto the Mg2Al-LDH NS through hydrogen bonding and eventually form a hydrogen bonded ordered network that facilitates the alignment of nanosheet dispersions during the coating process. Our results suggest that the ageing of inorganic nanosheet dispersions in PVA or other potential hydrogen bonding adhesive systems could be a general approach to improve the alignment of the nanosheets on the polymer film surface once applied and thus improve their performance characteristics for barrier coating applications.
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Affiliation(s)
- Jingfang Yu
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Chunping Chen
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | | | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Zhonghua Wu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Guang Mo
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Fei Xie
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Dermot O'Hare
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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14
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Luo Y, Wang C, Pang AP, Zhang X, Wang D, Lu X. Low-Concentration Salt Solution Changes the Interfacial Molecular Behavior of Polyelectrolyte Brushes. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00119] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Chu Wang
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Xiang Zhang
- National Center for International Joint Research of Micro−Nano Molding Technology, School of Mechanics & Engineering Science, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Dayang Wang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, Jilin Province, P. R. China
| | - Xiaolin Lu
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
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15
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Liu S, Lin YT, Bhat B, Kuan KY, Kwon JSI, Akbulut M. pH-responsive viscoelastic supramolecular viscosifiers based on dynamic complexation of zwitterionic octadecylamidopropyl betaine and triamine for hydraulic fracturing applications. RSC Adv 2021; 11:22517-22529. [PMID: 35480416 PMCID: PMC9034271 DOI: 10.1039/d1ra00257k] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 05/26/2021] [Indexed: 01/04/2023] Open
Abstract
Viscosity modifying agents are one of the most critical components of hydraulic fracturing fluids, ensuring the efficient transport and deposition of proppant into fissures. To improve the productivity index of hydraulic fracturing processes, better viscosifiers with a higher proppant carrying capacity and a lower potential of formation damage are needed. In this work, we report the development of a novel viscoelastic system relying on the complexation of zwitterionic octadecylamidopropyl betaine (OAPB) and diethylenetriamine (DTA) in water. At a concentration of 2 wt%, the zwitterionic complex fluid had a static viscosity of 9 to 200 poise, which could be reversibly adjusted by changing the suspension pH. The degree of pH-responsiveness ranged from 10 to 27 depending on the shear rate. At a given concentration and optimum pH value, the zwitterionic viscosifiers showed a two-orders-of-magnitude reduction in settling velocity of proppant compared to polyacrylamide solution (slickwater). By adjusting the pH between 4 and 8, the networked structure of the gel could be fully assembled and disassembled. The lack of macromolecular residues at the dissembled state can be beneficial for hydraulic fracturing application in avoiding the permeation damage issues encountered in polymer and linear-gel-based fracturing fluids. The reusability and the unnecessary permanent breakers are other important characteristics of these zwitterionic viscosifiers. Viscosity modifying agents are one of the most critical components of hydraulic fracturing fluids, ensuring the efficient transport and deposition of proppant into fissures.![]()
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Affiliation(s)
- Shuhao Liu
- Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station TX 77843 USA
| | - Yu-Ting Lin
- Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station TX 77843 USA
| | - Bhargavi Bhat
- Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station TX 77843 USA
| | - Kai-Yuan Kuan
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Joseph Sang-Ii Kwon
- Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station TX 77843 USA .,Texas A&M Energy Institute College Station TX 77843 USA
| | - Mustafa Akbulut
- Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station TX 77843 USA .,Department of Materials Science and Engineering, Texas A&M University College Station TX 77843 USA.,Texas A&M Energy Institute College Station TX 77843 USA
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16
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Mushtaq R, Abbas MA, Mushtaq S, Ahmad NM, Khan NA, Khan AU, Hong W, Sadiq R, Jiang Z. Antifouling and Flux Enhancement of Reverse Osmosis Membrane by Grafting Poly (3-Sulfopropyl Methacrylate) Brushes. MEMBRANES 2021; 11:213. [PMID: 33803777 PMCID: PMC8003146 DOI: 10.3390/membranes11030213] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 12/24/2022]
Abstract
A commercial thin film composite (TFC) polyamide (PA) reverse osmosis membrane was grafted with 3-sulfopropyl methacrylate potassium (SPMK) to produce PA-g-SPMK by atom transfer radical polymerization (ATRP). The grafting of PA was done at varied concentrations of SPMK, and its effect on the surface composition and morphology was studied by Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), optical profilometry, and contact angle analysis. The grafting of hydrophilic ionically charged PSPMK polymer brushes having acrylate and sulfonate groups resulted in enhanced hydrophilicity rendering a reduction of contact angle from 58° of pristine membrane sample labeled as MH0 to 10° for a modified membrane sample labeled as MH3. Due to the increased hydrophilicity, the flux rate rises from 57.1 L m-2 h-1 to 71.2 L m-2 h-1, and 99% resistance against microbial adhesion (Escherichia coli and Staphylococcus aureus) was obtained for MH3 after modification.
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Affiliation(s)
- Reema Mushtaq
- Polymer Research Lab, School of Chemical and Material Engineering, NUST, H-12, Islamabad 44000, Pakistan; (R.M.); (M.A.A.); (S.M.)
| | - Muhammad Asad Abbas
- Polymer Research Lab, School of Chemical and Material Engineering, NUST, H-12, Islamabad 44000, Pakistan; (R.M.); (M.A.A.); (S.M.)
| | - Shehla Mushtaq
- Polymer Research Lab, School of Chemical and Material Engineering, NUST, H-12, Islamabad 44000, Pakistan; (R.M.); (M.A.A.); (S.M.)
| | - Nasir M. Ahmad
- Polymer Research Lab, School of Chemical and Material Engineering, NUST, H-12, Islamabad 44000, Pakistan; (R.M.); (M.A.A.); (S.M.)
| | - Niaz Ali Khan
- Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (W.H.); (Z.J.)
| | - Asad U. Khan
- Department of Chemical Engineering, COMSATS University Islamabad, Lahore Campus, Lahore 54000, Pakistan;
| | - Wu Hong
- Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (W.H.); (Z.J.)
| | - Rehan Sadiq
- School of Engineering, University of British Columbia (Okanagan), 3333 University Way, Kelowna, BC V1V 1V7, Canada;
| | - Zhongyi Jiang
- Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; (W.H.); (Z.J.)
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17
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Zhang S, Andre JS, Hsu L, Toolis A, Esarey SL, Li B, Chen Z. Nondestructive In Situ Detection of Chemical Reactions at the Buried Interface between Polyurethane and Isocyanate-Based Primer. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01862] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Shuqing Zhang
- Department of Macromolecular Science and Engineering, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - John S Andre
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Lorraine Hsu
- Coatings and Innovation Center, PPG, 4325 Rosanna Drive, Allison Park, Pennsylvania 15101, United States
| | - Amy Toolis
- Coatings and Innovation Center, PPG, 4325 Rosanna Drive, Allison Park, Pennsylvania 15101, United States
| | - Samuel L Esarey
- Coatings and Innovation Center, PPG, 4325 Rosanna Drive, Allison Park, Pennsylvania 15101, United States
| | - Bolin Li
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Zhan Chen
- Department of Macromolecular Science and Engineering, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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18
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Wang T, Kou R, Zhang J, Zhu R, Cai H, Liu G. Tuning the Light Response of Strong Polyelectrolyte Brushes with Counterions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:13051-13059. [PMID: 33094611 DOI: 10.1021/acs.langmuir.0c02494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, a negatively charged poly(3-sulfopropyl methacrylate potassium) (PSPMA) brush has been employed as a model system to demonstrate the tuning of the light response of strong polyelectrolyte brushes (SPBs) with counterions. The substitution of K+ counterions by azobenzene-containing counterions (Azo-N+) renders the PSPMA brush light-responsive in aqueous solutions. Nevertheless, the strength of the light response of the PSPMA brush is weak due to the inefficient disassembly of the micelle-like aggregates in the brush upon irradiation with ultraviolet light. Counterion mixtures of Azo-N+ and K+ are employed to realize a strong light response of the PSPMA brush by incorporating a reasonable amount of Azo-N+ counterions into the brush. The strength of the light response of the PSPMA brush can be tuned by the mole ratio of Azo-N+ to K+. Furthermore, properties including the hydration and conformation of the PSPMA brush can be reversibly switched via alternating ultraviolet and visible light irradiation. This work opens up the opportunities available for the use of counterions to tune the light response of SPBs.
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Affiliation(s)
- Tao Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
- School of Materials Science and Engineering, Jiangxi Key Laboratory for Two-Dimensional Materials, Nanchang University, Nanchang, 330031, P. R. China
| | - Ran Kou
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Jian Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Renwei Zhu
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Hongtao Cai
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Guangming Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
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19
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Zhang J, Xu S, Jin H, Liu G. Ionic hydrogen bond effects on polyelectrolyte brushes beyond the hydronium and hydroxide ions. Chem Commun (Camb) 2020; 56:10930-10933. [PMID: 32940269 DOI: 10.1039/d0cc03763j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Herein, we have demonstrated that the properties of both strong and weak polyelectrolyte brushes including hydration, stiffness, conformation, and wettability can be tuned by the hydrogen bonding between the bound counterions and the grafted chains beyond the hydronium and hydroxide ions. This will greatly extend the application of ionic hydrogen bond effects in polymer systems.
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Affiliation(s)
- Jian Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, P. R. China.
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20
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Hou J, Sun G, Liu J, Gao X, Zhang X, Lu Z. Liquid/Vapor Interface of Dimethyl Carbonate-Methanol Binary Mixtures Investigated by Sum Frequency Generation Vibrational Spectroscopy and Molecular Dynamics Simulation. J Phys Chem B 2020; 124:4211-4221. [PMID: 32338908 DOI: 10.1021/acs.jpcb.0c01566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the present work, the dimethyl carbonate (DMC)-methanol binary mixture was used as a benchmark system to study the molecular structures of the liquid/vapor interface of organic-organic mixtures by sum frequency generation vibrational spectroscopy (SFG-VS) and molecular dynamics (MD) simulations. It was discovered that both the methanol and DMC molecules are anisotropically oriented at the surface, yielding strong SFG-VS signals in the C-H stretching frequency range for both molecules. The detailed analyses of the spectroscopic and MD data reveal that the increase of the methanol bulk concentrations reduces the orientational order of the methyl groups for both the interfacial DMC and methanol molecules but does not significantly affect the orientations of the carbonyl group in DMC. Moreover, no obvious correlations were found between the room-temperature orientations of the surface molecules and the azeotropic mole fraction. The present work paves the road for future investigations on the molecular structures of the liquid/vapor interfaces of other organic-organic mixtures, especially those that are important in industrial separations.
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Affiliation(s)
- Jian Hou
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guanlun Sun
- School of Chemical Engineering and Technology, National Engineering Research Center of Distillation Technology, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
| | - Jianchuan Liu
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Gao
- School of Chemical Engineering and Technology, National Engineering Research Center of Distillation Technology, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China
| | - Xianyi Zhang
- Anhui Province Key Laboratory of Optoelectronic Material Science and Technology, School of Physics and Electronic Information, Anhui Normal University, Wuhu, Anhui 241002, China
| | - Zhou Lu
- Anhui Province Key Laboratory of Optoelectronic Material Science and Technology, School of Physics and Electronic Information, Anhui Normal University, Wuhu, Anhui 241002, China
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21
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Yuan H, Liu G. Ionic effects on synthetic polymers: from solutions to brushes and gels. SOFT MATTER 2020; 16:4087-4104. [PMID: 32292998 DOI: 10.1039/d0sm00199f] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The ionic effects on synthetic polymers have attracted extensive attention due to the crucial role of ions in the determination of the properties of synthetic polymers. This review places the focus on specific ion effects, multivalent ion effects, and ionic hydrophilicity/hydrophobicity effects in synthetic polymer systems from solutions to brushes and gels. The specific ion effects on neutral polymers are determined by both the direct and indirect specific ion-polymer interactions, whereas the ion specificities of charged polymers are mainly dominated by the specific ion-pairing interactions. The ionic cross-linking effect exerted by the multivalent ions is widely used to tune the properties of polyelectrolytes, while the reentrant behavior of polyelectrolytes in the presence of multivalent ions still remains poorly understood. The ionic hydrophilicity/hydrophobicity effects not only can be applied to make strong polyelectrolytes thermosensitive, but also can be used to prepare polymeric nano-objects and to control the wettability of polyelectrolyte brush-modified surfaces. The not well-studied ionic hydrogen bond effects are also discussed in the last section of this review.
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Affiliation(s)
- Haiyang Yuan
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, No. 96, Jinzhai Road, Hefei 230026, P. R. China.
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22
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Cai H, Kou R, Liu G. Counterion-Tunable Thermosensitivity of Strong Polyelectrolyte Brushes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:16862-16868. [PMID: 31774295 DOI: 10.1021/acs.langmuir.9b02982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this work, poly(sodium styrene sulfonate) brushes have been employed as a precursor to prepare thermosensitive strong polyelectrolyte brushes (SPBs) through a counterion exchange strategy. The substitution of hydrophilic Na+ counterions by hydrophobic tetraalkylphosphonium counterions leads to a thermoresponsivity of the SPBs. The thermosensitive properties including hydration, stiffness, and surface water wettability of the SPBs can be modulated by the type of the tetraalkylphosphonium counterions. Nevertheless, the wet thickness of the SPBs with tetraalkylphosphonium counterions does not exhibit an obvious temperature dependency due to the high steric barrier in the crowded environment of SPBs generated by the large tetraalkylphosphonium counterions. The mixtures of small Na+ counterions and large tetraalkylphosphonium counterions are employed to realize the thermosensitive wet thickness without sacrificing other thermoresponsive properties of the SPBs because the mixed counterions can bring both a certain hydrophobicity and some free space to the brushes. This work opens up the opportunities available for the use of counterions to tune the thermosensitivity of SPBs.
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Affiliation(s)
- Hongtao Cai
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics , University of Science and Technology of China , No. 96, JinZhai Road , Hefei 230026 , P. R. China
| | - Ran Kou
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics , University of Science and Technology of China , No. 96, JinZhai Road , Hefei 230026 , P. R. China
| | - Guangming Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics , University of Science and Technology of China , No. 96, JinZhai Road , Hefei 230026 , P. R. China
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23
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Liu G. Tuning the Properties of Charged Polymers at the Solid/Liquid Interface with Ions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:3232-3247. [PMID: 29806944 DOI: 10.1021/acs.langmuir.8b01158] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In conventional theories, where ions are treated as point charges, the properties of charged polymers can be tuned using ions via the ionic strength. However, this article will show that the properties of charged polymers at the solid/liquid interface, including charged polymer brushes and polyelectrolyte multilayers, can be tuned by ions beyond ionic strength effects. Ion specificity, multivalency, ionic hydrogen bonding, and ionic hydrophobicity/hydrophilicity are used to tune a range of properties of charged polymers at the solid/liquid interface such as hydration, conformation, stiffness, surface wettability, lubricity, adhesion, and protein adsorption. The ionic effects demonstrated here greatly broaden our understanding of the use of ions to tune the interfacial properties of charged polymers. It is anticipated that these ionic effects can be further expanded by incorporating new types of important ion-charged polymer interactions and can also be extended to neutral polymer systems.
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Affiliation(s)
- Guangming Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics , University of Science and Technology of China , Hefei , P. R. China 230026
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24
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Pomorska A, Wolski K, Wytrwal-Sarna M, Bernasik A, Zapotoczny S. Polymer brushes grafted from nanostructured zinc oxide layers – Spatially controlled decoration of nanorods. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.01.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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25
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Zhang J, Cai H, Tang L, Liu G. Tuning the pH Response of Weak Polyelectrolyte Brushes with Specific Anion Effects. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:12419-12427. [PMID: 30220208 DOI: 10.1021/acs.langmuir.8b02776] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The positively charged poly( N, N'-dimethylaminoethyl methacrylate) (PDMAEMA) brushes have been employed as model weak polyelectrolyte brushes (WPBs) to demonstrate the tuning of the pH response of WPBs with specific anion effects. The charge density of PDMAEMA brushes can be modulated by specific ion-pairing interactions between counterions and the protonated dimethylamino group; as a result, the strength of the pH response of PDMAEMA brushes can be tuned by specific anion effects. A more chaotropic counterion can more strongly interact with the protonated dimethylamino group, thereby more effectively neutralizing the positively charged group associated with the grafted weak polyelectrolyte chains and more remarkably suppressing the pH response of PDMAEMA brushes. Although the pH response of PDMAEMA brushes is insensitive to the anion identity at a low salt concentration, it can be tuned by specific anion effects at relatively high salt concentrations. Our study demonstrates that the pH-responsive properties of PDMAEMA brushes including hydration, conformation, oil wettability, and adhesion can be tuned by specific anion effects. The work presented here provides a method to tune the pH response of WPBs by the anion identity.
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Affiliation(s)
- Jian Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics , University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Hongtao Cai
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics , University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Ling Tang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics , University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Guangming Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics , University of Science and Technology of China , Hefei 230026 , P. R. China
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26
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Ge A, Qiao L, Seo JH, Yui N, Ye S. Surface-Restructuring Differences between Polyrotaxanes and Random Copolymers in Aqueous Environment. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:12463-12470. [PMID: 30216076 DOI: 10.1021/acs.langmuir.8b02676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the present study, we investigated the surface reorganization behaviors and adsorption conformations of fibrinogen on the surface of polyrotaxanes containing different amounts of α-cyclodextrin (α-CD) by using surface-sensitive vibrational spectroscopy sum frequency generation (SFG). For comparison, behaviors of the surface restructuring and fibrinogen adsorption on the random copolymers containing similar terminal groups were also investigated. It was found that larger amounts of BMA moieties of polyrotaxanes form ordered surface structures after immersion in water for 48 h. Furthermore, the polyrotaxane surfaces exhibit a much higher capability of fibrinogen adsorption than the random copolymer surfaces. The water-induced surface restructuring of the polyrotaxane films slightly affects the adsorption structure of the fibrinogen molecules.
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Affiliation(s)
- Aimin Ge
- Institute for Catalysis , Hokkaido University , Sapporo 001-0021 , Japan
| | - Lin Qiao
- Institute for Catalysis , Hokkaido University , Sapporo 001-0021 , Japan
| | - Ji-Hun Seo
- Institute of Biomaterials and Bioengineering , Tokyo Medical and Dental University , Tokyo 101-0062 , Japan
| | - Nobuhiko Yui
- Institute of Biomaterials and Bioengineering , Tokyo Medical and Dental University , Tokyo 101-0062 , Japan
| | - Shen Ye
- Department of Chemistry, Graduate School of Science , Tohoku University , Sendai 980-8578 , Japan
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Xu X, Billing M, Ruths M, Klok HA, Yu J. Structure and Functionality of Polyelectrolyte Brushes: A Surface Force Perspective. Chem Asian J 2018; 13:3411-3436. [PMID: 30080310 DOI: 10.1002/asia.201800920] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Indexed: 11/11/2022]
Abstract
The unique functionality of polyelectrolyte brushes depends on several types of specific interactions, including solvent structure effects, hydrophobic forces, electrostatic interactions, and specific ion interactions. Subtle variations in the solution environment can lead to conformational and surface structural changes of the polyelectrolyte brushes, which are mainly discussed from a surface-interaction perspective in this Focus Review. A brief overview is given of recent theoretical and experimental progress in the structure of polyelectrolyte brushes in various environments. Two important techniques for surface-force measurements are described, the surface forces apparatus (SFA) and atomic force microscopy (AFM), and some recent results on polyelectrolyte brushes are shown. Lastly, this Focus Review highlights the use of these surface-grafted polyelectrolyte brushes in the creation of functional surfaces for various applications, including nonfouling surfaces, boundary lubricants, and stimuli-responsive surfaces.
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Affiliation(s)
- Xin Xu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.,Department of Chemistry, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Mark Billing
- Institut des Matériaux et Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, École Polytechnique Fédérale de Lausanne (EPFL), Bâtiment MXD, Station 12, CH-1015, Lausanne, Switzerland
| | - Marina Ruths
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Harm-Anton Klok
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.,Institut des Matériaux et Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, École Polytechnique Fédérale de Lausanne (EPFL), Bâtiment MXD, Station 12, CH-1015, Lausanne, Switzerland
| | - Jing Yu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
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Behavior of a strong polyelectrolyte, poly(diallyldimethylammonium chloride) physisorbed at oil-water interface under different environments : A comparison with a weak polyelectrolyte. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2018.04.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Kou R, Zhang J, Chen Z, Liu G. Counterion Specificity of Polyelectrolyte Brushes: Role of Specific Ion-Pairing Interactions. Chemphyschem 2018; 19:1404-1413. [PMID: 29575481 DOI: 10.1002/cphc.201701256] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Indexed: 11/10/2022]
Abstract
We demonstrate here that the properties of poly (2-(methacryloyloxy) ethyl trimethylammonium chloride) brushes can be tuned by counterion species. When the brushes are exposed to external chloride (Cl- ) counterions, obvious dehydration and collapse are only observed at high salt concentrations. In the presence of very strongly chaotropic perchlorate (ClO4- ), the brushes strongly dehydrate and collapse at a very low salt concentration. For the strongly chaotropic thiocyanate ion (SCN- ), the changes in hydration and conformation of the brushes are similar to those observed for ClO4- but at a smaller extent at very low salt concentrations. With the addition of kosmotropic acetate (Ac- ), hydration of the brushes increases, accompanied by a swelling of the brushes in the low-salt-concentration regime. In contrast, the brushes dehydrate and collapse with increasing concentration of Ac- in the high-salt-concentration regime. The counterion specificity of the brushes demonstrated here is determined by specific ion-pairing interactions through modulating the osmotic pressure within the brushes and the hydrophobicity of the ion pairs.
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Affiliation(s)
- Ran Kou
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Jian Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Zhen Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Guangming Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China
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Wang RY, Guo XS, Fan B, Zou SF, Cao XH, Tong ZZ, Xu JT, Du BY, Fan ZQ. Design and Regulation of Lower Disorder-to-Order Transition Behavior in the Strongly Interacting Block Copolymers. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00227] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Rui-Yang Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiao-Shuai Guo
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Bin Fan
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Shu-Fen Zou
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiao-Han Cao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zai-Zai Tong
- Key Laboratory of Advanced Textile Materials and Manufacturing Technology (ATMT), Ministry of Education, Department of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jun-Ting Xu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Bin-Yang Du
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zhi-Qiang Fan
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
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Tan J, Luo Y, Ye S. A Highly Sensitive Femtosecond Time-Resolved Sum Frequency Generation Vibrational Spectroscopy System with Simultaneous Measurement of Multiple Polarization Combinations. CHINESE J CHEM PHYS 2017. [DOI: 10.1063/1674-0068/30/cjcp1706114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Junjun Tan
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yi Luo
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Shuji Ye
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
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32
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Li Y, He L, Zhang X, Zhang N, Tian D. External-Field-Induced Gradient Wetting for Controllable Liquid Transport: From Movement on the Surface to Penetration into the Surface. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1703802. [PMID: 29052911 DOI: 10.1002/adma.201703802] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 09/02/2017] [Indexed: 06/07/2023]
Abstract
External-field-responsive liquid transport has received extensive research interest owing to its important applications in microfluidic devices, biological medical, liquid printing, separation, and so forth. To realize different levels of liquid transport on surfaces, the balance of the dynamic competing processes of gradient wetting and dewetting should be controlled to achieve good directionality, confined range, and selectivity of liquid wetting. Here, the recent progress in external-field-induced gradient wetting is summarized for controllable liquid transport from movement on the surface to penetration into the surface, particularly for liquid motion on, patterned wetting into, and permeation through films on superwetting surfaces with external field cooperation (e.g., light, electric fields, magnetic fields, temperature, pH, gas, solvent, and their combinations). The selected topics of external-field-induced liquid transport on the different levels of surfaces include directional liquid motion on the surface based on the wettability gradient under an external field, partial entry of a liquid into the surface to achieve patterned surface wettability for printing, and liquid-selective permeation of the film for separation. The future prospects of external-field-responsive liquid transport are also discussed.
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Affiliation(s)
- Yan Li
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Chemistry, Beihang University, Beijing, 100191, P. R. China
| | - Linlin He
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Chemistry, Beihang University, Beijing, 100191, P. R. China
| | - Xiaofang Zhang
- School of Mathematics and Physics, University of Science & Technology Beijing, Beijing, 100083, P. R. China
| | - Na Zhang
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Chemistry, Beihang University, Beijing, 100191, P. R. China
| | - Dongliang Tian
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Chemistry, Beihang University, Beijing, 100191, P. R. China
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Wang W, Ye S. Molecular interactions of organic molecules at the air/water interface investigated by sum frequency generation vibrational spectroscopy. Phys Chem Chem Phys 2017; 19:4488-4493. [PMID: 28120952 DOI: 10.1039/c6cp07827c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The molecular structure and dynamics of organic molecules at the aqueous interface have attracted a number of investigations owing to their importance and specific nature. However, there are relatively few studies on the direct characterization of the molecular interactions at the air/water interface because they are extremely difficult to measure in experiments. In this study, we use dibutyl ester molecules (R1CO2R2O2CR1) as a model of organic molecules, and investigate their molecular structure and interactions using sum frequency generation vibrational spectroscopy. We demonstrate that the molecular interactions can be estimated by measuring the intensity ratio of the symmetric stretching (ν1) and Fermi resonant bands (2ν2) of methyl groups. Here, dibutyl ester molecules are widely used as plasticizers in polymers to improve the properties of the plastics and polymers. It is found that the orientation angles of the tailed methyl groups at the air/water interface decrease from 34° to 19° when the chain length of R2 increases from 0 to 8. The total intermolecular interactions of the dibutyl ester molecules decrease as the chain length of R2 increases because the van der Waals interactions between the hydrocarbon chains increase, while the hydrogen bond interactions between the carbonyl group and water molecules decrease. Our study demonstrates the stability of ester-based plasticizers in polymers can be well predicted from the intensity ratio of the ν1 and 2ν2 bands of methyl group. Such an intensity ratio can be thus used as an effective vibrational optical ruler for characterizing molecular interactions between plasticizers and polymers.
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Affiliation(s)
- Wenting Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China. and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Shuji Ye
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China. and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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34
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Abstract
This review summarizes pH-responsive monomers, polymers and their derivative nano- and micro-structures including micelles, cross-linked micelles, microgels and hydrogels.
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Affiliation(s)
- G. Kocak
- Department of Chemistry
- Faculty of Arts and Science
- Eskisehir Osmangazi University
- Eskisehir
- Turkey
| | - C. Tuncer
- Department of Chemistry
- Faculty of Arts and Science
- Eskisehir Osmangazi University
- Eskisehir
- Turkey
| | - V. Bütün
- Department of Chemistry
- Faculty of Arts and Science
- Eskisehir Osmangazi University
- Eskisehir
- Turkey
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