Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression
One of the emerging water desalination techniques relies on the compression of a polyelectrolyte gel. The pressures needed reach tens of bars, which are too high for many applications, damage the gel and prevent its reuse. Here, we study the process by means of coarse-grained simulations of hydropho...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-03-01
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| Series: | Gels |
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| Online Access: | https://www.mdpi.com/2310-2861/9/3/259 |
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| author | Alexander D. Kazakov Varvara M. Prokacheva Oleg V. Rud Lucie Nová Filip Uhlík |
| author_facet | Alexander D. Kazakov Varvara M. Prokacheva Oleg V. Rud Lucie Nová Filip Uhlík |
| author_sort | Alexander D. Kazakov |
| collection | DOAJ |
| description | One of the emerging water desalination techniques relies on the compression of a polyelectrolyte gel. The pressures needed reach tens of bars, which are too high for many applications, damage the gel and prevent its reuse. Here, we study the process by means of coarse-grained simulations of hydrophobic weak polyelectrolyte gels and show that the necessary pressures can be lowered to only a few bars. We show that the dependence of applied pressure on the gel density contains a plateau indicating a phase separation. The phase separation was also confirmed by an analytical mean-field theory. The results of our study show that changes in the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>pH</mi></semantics></math></inline-formula> or salinity can induce the phase transition in the gel. We also found that ionization of the gel enhances its ion capacity, whereas increasing the gel hydrophobicity lowers the pressure required for gel compression. Therefore, combining both strategies enables the optimization of polyelectrolyte gel compression for water desalination purposes. |
| first_indexed | 2024-03-11T06:29:48Z |
| format | Article |
| id | doaj.art-27e23c569a7f4790b6271c6f2547ceaf |
| institution | Directory Open Access Journal |
| issn | 2310-2861 |
| language | English |
| last_indexed | 2024-03-11T06:29:48Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Gels |
| spelling | doaj.art-27e23c569a7f4790b6271c6f2547ceaf2023-11-17T11:15:34ZengMDPI AGGels2310-28612023-03-019325910.3390/gels9030259Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under CompressionAlexander D. Kazakov0Varvara M. Prokacheva1Oleg V. Rud2Lucie Nová3Filip Uhlík4Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech RepublicDepartment of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech RepublicDepartment of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech RepublicDepartment of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech RepublicDepartment of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech RepublicOne of the emerging water desalination techniques relies on the compression of a polyelectrolyte gel. The pressures needed reach tens of bars, which are too high for many applications, damage the gel and prevent its reuse. Here, we study the process by means of coarse-grained simulations of hydrophobic weak polyelectrolyte gels and show that the necessary pressures can be lowered to only a few bars. We show that the dependence of applied pressure on the gel density contains a plateau indicating a phase separation. The phase separation was also confirmed by an analytical mean-field theory. The results of our study show that changes in the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>pH</mi></semantics></math></inline-formula> or salinity can induce the phase transition in the gel. We also found that ionization of the gel enhances its ion capacity, whereas increasing the gel hydrophobicity lowers the pressure required for gel compression. Therefore, combining both strategies enables the optimization of polyelectrolyte gel compression for water desalination purposes.https://www.mdpi.com/2310-2861/9/3/259polyelectrolyte hydrogelssimulationsdesalinationhydrophobic gelsweak polyelectrolytesvolume-phase transition |
| spellingShingle | Alexander D. Kazakov Varvara M. Prokacheva Oleg V. Rud Lucie Nová Filip Uhlík Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression Gels polyelectrolyte hydrogels simulations desalination hydrophobic gels weak polyelectrolytes volume-phase transition |
| title | Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression |
| title_full | Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression |
| title_fullStr | Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression |
| title_full_unstemmed | Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression |
| title_short | Modeling the Phase Transition in Hydrophobic Weak Polyelectrolyte Gels under Compression |
| title_sort | modeling the phase transition in hydrophobic weak polyelectrolyte gels under compression |
| topic | polyelectrolyte hydrogels simulations desalination hydrophobic gels weak polyelectrolytes volume-phase transition |
| url | https://www.mdpi.com/2310-2861/9/3/259 |
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