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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
Interactions of an anionic surfactant with poly(oxyalkylene) copolymers in aqueous solution
Antonios Kelarakis1, Chiraphon Chaibundit, Marta J Krysmann
1National and Kapodistrian University of Athens, Department of Chemistry, Physical Chemistry Laboratory, Panepistimiopolis, 157 71 Athens, Greece. akelar@cc.uoa.gr
Journal of Colloid and Interface Science
|November 4, 2008
Summary
Sodium dodecyl sulfate (SDS) interactions with poly(ethylene oxide)/poly(alkylene oxide) (E/A) block copolymers influence self-assembly. SDS can induce large aggregates or micellar suppression, depending on copolymer composition, affecting particle formation.
Area of Science:
- Polymer Science
- Surfactant Chemistry
- Materials Science
Background:
- Poly(ethylene oxide)/poly(alkylene oxide) (E/A) block copolymers exhibit complex self-assembly in aqueous solutions.
- Ionic surfactants like sodium dodecyl sulfate (SDS) can significantly alter copolymer solution behavior.
- Understanding these interactions is crucial for designing novel materials and applications.
Purpose of the Study:
- To investigate the impact of sodium dodecyl sulfate (SDS) on the self-assembly of various poly(ethylene oxide)/poly(alkylene oxide) (E/A) block copolymers.
- To elucidate the mechanisms behind SDS-induced changes in copolymer aggregation behavior.
- To analyze the thermodynamic properties of these polymer-surfactant systems.
Main Methods:
- Synthesis and characterization of E/A block copolymers.
- Solution studies of copolymer-SDS interactions at varying compositions.
- Analysis of critical micelle concentrations (cmc(*)) using regular solution theory.
- Ultrasonic studies to probe complexation dynamics.
Main Results:
- SDS induced distinct self-assembly behaviors: large aggregates for E(18)B(10)-SDS and micellar suppression for other E/A copolymers.
- Micellar suppression was attributed to physical binding between SDS and copolymer hydrophobic blocks.
- Analysis of cmc(*) revealed both positive and negative deviations from ideal behavior, indicating complex interactions.
- Ultrasonic studies for E(19)P(43)E(19)-SDS identified three stages of complexation: SDS adsorption, complex formation, and aggregate breakdown.
Conclusions:
- The effect of SDS on E/A copolymer self-assembly is highly dependent on copolymer structure and composition.
- SDS can either promote aggregate formation or suppress micellization through specific binding mechanisms.
- Regular solution theory and ultrasonic studies provide valuable insights into the thermodynamics and kinetics of polymer-surfactant complexation.
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