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Published on: April 10, 2017
Aqueous suspensions of natural swelling clay minerals. 2. Rheological characterization
Erwan Paineau1, Laurent J Michot, Isabelle Bihannic
1Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL, UMR 7569, BP40 54501 Vandœuvre, Cedex France. erwan.paineau@ensg.inpl-nancy.fr
Langmuir : the ACS Journal of Surfaces and Colloids
|May 20, 2011
Summary
This study reveals how clay particle volume, repulsion strength, and size influence colloidal clay suspensions
Area of Science:
- Colloid and Surface Science
- Materials Science
- Rheology
Background:
- Colloidal clay minerals exhibit complex viscoelastic behavior in aqueous solutions.
- Understanding this behavior is crucial for applications in various industries.
Purpose of the Study:
- To comprehensively investigate the viscoelastic properties of natural colloidal clay minerals.
- To identify key parameters governing their rheological behavior and sol-gel transitions.
Main Methods:
- Rheological experiments were conducted under dynamic and steady-state conditions.
- Analysis included elasticity, yield stress, particle volume, ionic strength, and electrostatic interactions.
- A simplified model based on statistical hydrodynamic trapping was proposed.
Main Results:
- Viscoelastic parameters (elasticity, yield stress) can be renormalized by particle volume, but differences arise from repulsion strength and charge location.
- A universal linear relationship between elasticity and yield stress was observed for various colloidal suspensions.
- The sol-gel transition is dependent on particle size, with larger particles gelling at higher volume fractions due to hydrodynamic trapping.
Conclusions:
- Particle volume, repulsion strength, and hydrodynamic interactions are critical factors in the viscoelasticity and gelation of clay suspensions.
- The findings offer a generalized understanding of colloidal suspension behavior and sol-gel transitions.
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