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Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
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Cationic Sterically Stabilized Diblock Copolymer Nanoparticles Exhibit Exceptional Tolerance toward Added Salt
Sarah J Byard1, Adam Blanazs2, John F Miller3
1Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , South Yorkshire S3 7HF , United Kingdom.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 9, 2019
Summary
New cationic diblock copolymer nanoparticles show excellent colloidal stability in concentrated salt solutions, crucial for applications like enhanced oil recovery. These materials maintain stability even in extreme salinity, offering insights into colloidal behavior in harsh environments.
Area of Science:
- Materials Science
- Polymer Chemistry
- Colloid Science
Background:
- Sterically stabilized colloidal dispersions with high salt tolerance are needed for commercial applications, including enhanced oil recovery.
- Developing robust nanoparticles that maintain stability in concentrated aqueous salt solutions is a significant challenge.
Purpose of the Study:
- To synthesize and characterize novel cationic diblock copolymer nanoparticles with enhanced colloidal stability in high salt concentrations.
- To investigate the effect of copolymer composition and morphology on nanoparticle stability in saline environments.
Main Methods:
- Synthesis of poly(2-(acryloyloxy)ethyltrimethylammonium chloride)-poly(diacetone acrylamide) (PATAC-PDAAM) diblock copolymers via reversible addition-fragmentation chain transfer (RAFT) aqueous dispersion polymerization.
- Characterization using transmission electron microscopy (TEM) and dynamic light scattering (DLS) to determine size, morphology, and colloidal stability.
- Electrophoretic light scattering (ELS) was used to determine zeta potentials in high salt media.
Main Results:
- Spherical nanoparticles were successfully synthesized, with size tunable by adjusting the degree of polymerization of the PDAAM block.
- PATAC-PDAAM spheres demonstrated remarkable colloidal stability in up to 4.0 M KCl and 3.0 M ammonium sulfate for over 115 days.
- High mole fractions of PATAC in the stabilizer shell (≥ 0.75) were necessary for stability in 4.0 M KCl; cationic worms and vesicles showed stability up to 2.0 M and 1.0 M KCl, respectively.
Conclusions:
- Cationic diblock copolymer nanoparticles offer excellent colloidal stability in highly concentrated salt solutions.
- These nanoparticles serve as valuable model systems for understanding the behavior of colloidal dispersions in extreme saline conditions.
- The findings have implications for developing advanced materials for demanding industrial applications.
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