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Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
The effect of shear on colloidal aggregation and gelation studied using small-angle light scattering
Tahereh Mokhtari1, A Chakrabarti, Christopher M Sorensen
1Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
Journal of Colloid and Interface Science
|September 6, 2008
Summary
Low shear rates enhance colloidal aggregation and gelation in polystyrene particle systems. Shear-induced growth can form hybrid superaggregates in dense colloidal systems.
Area of Science:
- Colloid and Surface Science
- Rheology of Dispersions
Background:
- Colloidal systems undergo aggregation and gelation over time.
- Understanding the influence of external forces on these processes is crucial.
Purpose of the Study:
- To investigate the impact of low shear rates on the aggregation kinetics and morphology of colloidal systems.
- To examine shear effects in both dilute and dense cluster regimes.
Main Methods:
- In situ light scattering measurements were employed.
- A colloidal system of 20 nm polystyrene particles was studied.
- Shear was applied for a short duration at various aggregation stages.
Main Results:
- Low shear rates were found to enhance aggregation and gelation.
- Shear-induced growth was observed, leading to hybrid superaggregates in dense systems.
Conclusions:
- Shear is a significant factor influencing colloidal aggregation and gelation.
- The morphology of aggregates, including superaggregates, is shear-dependent, particularly in dense regimes.
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