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Updated: Jun 4, 2025
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Assembly and Characterization of Polyelectrolyte Complex Micelles
Published on: March 2, 2020
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Covalently Cross-Linked Polyelectrolyte Complex Nanoparticles with Enhanced Stability against Dissociation at High
Xiongyu Chen1, Zhenhe Zhang1, Hongxi Zhong1
1McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 23, 2024
Summary
Cross-linked polyelectrolyte complex nanoparticles (PECNPs) demonstrate remarkable stability in ultrahigh salinity. This innovation prevents nanoparticle dissociation, opening new avenues for subsurface energy and environmental applications.
Area of Science:
- Materials Science
- Colloid Science
- Polymer Chemistry
Background:
- Polyelectrolyte complex nanoparticles (PECNPs) typically dissociate at high salinities.
- This dissociation limits their application in challenging environments.
Purpose of the Study:
- To develop colloidally stable PECNPs that resist dissociation in ultrahigh salinity.
- To investigate the factors controlling PECNP stability and dissociation.
Main Methods:
- Cross-linking branched polyethylenimine (PEI) with poly(vinylsulfonate) (PVS).
- Exposure of cross-linked PECNPs to ultrahigh salinity solutions (up to 5.2 M NaCl, 5.4 M CaCl2).
- Monitoring nanoparticle size, polyanion release, and colloidal stability over time.
Main Results:
- Cross-linked PECNPs maintained colloidal stability and limited dissociation in solutions up to 5.2 M NaCl and 5.4 M CaCl2.
- Nanoparticle size and polyanion partition coefficient reached equilibrium within 24 hours and remained stable for 7 weeks.
- Both electrostatic and non-electrostatic (hydrophobic) interactions influenced the degree of dissociation.
Conclusions:
- Cross-linking PEI is an effective strategy to create stable PECNPs in ultrahigh salinity.
- Stable PECNPs offer new possibilities for fundamental studies and applications in controlled release for subsurface energy and environmental remediation.
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