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Studying Surfactant Effects on Hydrate Crystallization at Oil-Water Interfaces Using a Low-Cost Integrated Modular Peltier Device
Published on: March 18, 2020
Flow-induced effects in mixed surfactant mesophases.
1ISIS, CCLRC, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK.
The Journal of Physical Chemistry. B
|July 25, 2007
Summary
Spatially resolved small-angle neutron scattering (SANS) revealed how mixed surfactant microstructures respond to elongational flow. Different lamellar and micellar ratios in DHTAC/C18EO10 and DHTAC/Coco20 mixtures showed distinct flow-induced ordering behaviors.
Area of Science:
- Materials Science
- Soft Matter Physics
- Rheology
Background:
- Understanding surfactant mixture behavior under flow is crucial for applications in materials science and formulation.
- Mixed surfactant systems exhibit complex microstructures, including lamellar and micellar phases, influencing their macroscopic properties.
Purpose of the Study:
- To investigate the flow-induced microstructural response of two distinct dialkyl chain cationic and nonionic surfactant mixtures.
- To correlate differences in lamellar and micellar component ratios with observed flow behaviors.
Main Methods:
- Utilized spatially resolved small-angle neutron scattering (SANS) to probe microstructure.
- Employed a crossed-slot elongational flow cell to apply controlled flow fields.
Main Results:
- Observed complex orientational ordering in DHTAC/C18EO10, predominantly lamellar fragments.
- Identified differences in flow-induced responses between DHTAC/C18EO10 and DHTAC/Coco20 mixtures.
- The observed ordering in DHTAC/C18EO10 reflects competition between flow directions or phase separation.
Conclusions:
- The ratio of lamellar to micellar components significantly impacts the flow response of mixed surfactants.
- SANS is effective in elucidating microstructural evolution under elongational flow.
- Elongational flow can induce complex ordering and potential demixing in surfactant systems.
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