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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
Dynamics in anionic micelles: effect of phenyl ring.
V K Sharma1, S Mitra, M Johnson
1Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
The Journal of Physical Chemistry. B
|April 26, 2013
Summary
Quasi-elastic neutron scattering reveals that sodium dodecyl benzene sulfonate (SDBS) micelles exhibit slower global and internal dynamics compared to sodium dodecyl sulfate (SDS) micelles. This difference is attributed to the phenyl ring in SDBS, causing denser micellar packing.
Area of Science:
- Physical Chemistry
- Materials Science
- Surfactant Science
Background:
- Sodium dodecyl benzene sulfonate (SDBS) is a crucial surfactant in industrial applications.
- Understanding micellar dynamics is key to optimizing surfactant-based processes.
- Molecular architecture significantly influences surfactant behavior.
Purpose of the Study:
- To investigate the effect of molecular structure on micellar dynamics in SDBS.
- To compare the dynamics of SDBS micelles with the similar surfactant sodium dodecyl sulfate (SDS).
- To elucidate the role of the phenyl ring in SDBS micellar behavior.
Main Methods:
- Quasi-elastic neutron scattering (QENS) was employed to study micellar dynamics.
- Analysis focused on distinguishing between global and internal monomer motions within micelles.
- Data was compared between SDBS and SDS systems.
Main Results:
- Two distinct motions were observed in both SDBS and SDS micelles: global and internal.
- Global micellar diffusion was Fickian and significantly slower for SDBS than SDS.
- Internal motions were more hindered in SDBS micelles, suggesting denser packing due to π-stacking.
Conclusions:
- The phenyl ring in SDBS influences micellar dynamics, leading to reduced diffusion coefficients for both global and internal motions compared to SDS.
- SDBS micelles exhibit more restricted internal alkyl chain flexibility than SDS micelles.
- The findings highlight the impact of molecular architecture on surfactant micellar behavior and dynamics.
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