Book contents
- Frontmatter
- Contents
- Preface
- General list of symbols
- Useful physical constants and values
- 1 Introduction to colloid science and rheology
- 2 Hydrodynamic effects
- 3 Brownian hard spheres
- 4 Stable systems
- 5 Non-spherical particles
- 6 Colloidal attractions and flocculated dispersions
- 7 Thixotropy
- 8 Shear thickening
- 9 Rheometry of suspensions
- 10 Suspensions in viscoelastic media
- 11 Advanced topics
- Index
- References
6 - Colloidal attractions and flocculated dispersions
Published online by Cambridge University Press: 05 December 2011
- Frontmatter
- Contents
- Preface
- General list of symbols
- Useful physical constants and values
- 1 Introduction to colloid science and rheology
- 2 Hydrodynamic effects
- 3 Brownian hard spheres
- 4 Stable systems
- 5 Non-spherical particles
- 6 Colloidal attractions and flocculated dispersions
- 7 Thixotropy
- 8 Shear thickening
- 9 Rheometry of suspensions
- 10 Suspensions in viscoelastic media
- 11 Advanced topics
- Index
- References
Summary
Introduction
In the suspensions discussed in the preceding chapters, the particles did not show a tendency to cluster together as they were colloidally stable. In most real systems this condition is only achieved by taking appropriate measures during formulation as there are always interparticle forces present, in particular dispersion forces, which cause neighboring particles to attract each other. Consequently, many naturally occurring and man-made dispersions are more or less aggregated. Examples include mine tailings, drilling muds, and clay slurries, as well as latex paints, tomato ketchup, and even blood.
Attractive interparticle forces can have a significant effect on the microstructure and on various suspension properties. Therefore, controlling and manipulating the degree of clustering becomes very important in industrial processes such as coating, filtration, dewatering, oil drilling, or the handling of mine tailings. In some cases, e.g., solid-liquid separation, irreversible aggregation provides the best results. In most other applications, one targets a weaker and more reversible flocculation (see Chapter 1 for a definition of these terms) in order to generate an optimal rheological behavior. It is this latter type of system that will be mainly dealt with in the present chapter.
- Type
- Chapter
- Information
- Colloidal Suspension Rheology , pp. 180 - 227Publisher: Cambridge University PressPrint publication year: 2011