Rheological properties of colloidal

Ueltmam, R.N. and Green, H. "Rheological Properties of Colloidal Solutions, Pigment Suspensions, and Oil Mixtures," J. Applied Physics. 1943, 14, 569-576. 

Surface layers (adsorbed, solvated, ionic) are of considerable importance in controlling the stability and rheological properties of colloidal systems. Sedimentation methods have proven effective in the measurement of adsorbed layer thickness using equations similar to Equation 1 when the density of the layer could be estimated ( 7,8). The equation can be considerably simplified if the density... 

D. E. Tambe and M. M. Sharma, Hydrodynamics of thin liquid-films bounded by viscoelastic interfaces, J. Colloid Interface Sci. 147, 137-151 (1991) Factors controlling the stability of colloid-stabilized emulsions. 1. An experimental investigation, J. Colloid Interface Sci. 157, 244-253 (1993) Factors controlling the stability of colloid-stabilized emulsions. 2. A model for the rheological properties of colloid-laden interfaces, J. Colloid Interface Sci. 162, 1-10 (1994) Factors controlling the stability of colloid-stabilized emulsions. 3. Measurement of the rheological properties of colloid-laden interfaces, J. Colloid Interface Sci. 171, 456-462 (1995). 

Tambe DE, Sharma MM. Factors controlling the stability of colloid-stabilized emulsions. II. A model for the rheological properties of colloid-laden interfaces. J Colloid Interface Sci 1994 162 1-10. 

Flow or deformation involves the relative motion of adjacent elements of the material. As a consequence such processes are sensitive to interatomic or intermolecular forces. In the case of liquids containing dispersed particles, interparticle forces are also important. Because the rheological properties of colloidal suspensions exhibit such a rich variety of phenomena, rheological studies not only provide information on medium-particle and particle-particle interactions but also arc of immense technological importance. 

These general principles of mechanical testing now allow us to transition to a discussion of the principles for determining the structure-rheological properties of colloidal objects. 

Definition Aerosols are snspensions of solid or liquid particles in a gas. Dust, smoke, mists, fog, haze, and smog are various forms of common aerosols. Colloids are suspensions of solid particles in a liquid. Colloidal particles are typically in the range of nanometers to few microns. The rheological properties of colloidal suspensions are strongly affected by the donble-layer forces. Emulsions are suspensions of droplets of liquids in another immiscible liquid. 

Chapter 8 starts the presentation of colloidal properties. Chapters 8 and 9 discuss the kinetic, optical and rheological properties of colloids and we illustrate how measurements on these properties can yield important information for the colloidal particles especially their molecular weight and shape. 

The study of the rheological properties of colloid systems has contributed to a high degree to clarify the ideas on these systems. It is however necessary as a preliminary to define various concepts h... 

Many properties of colloidal suspensions, such as their stability, rheology, and phase behaviour, are closely related to the interactions between the suspended particles. The background of the most important contributing factors to these interactions is discussed in this section. 

J. Lakatos-Szabd and I. Lakatos. Effect of sodium hydroxide on interfacial rheological properties of oil-water systems. In Colloids Surfaces, Sect A, volume 149, pages 507-513. 9th Surface Colloid Sci Int Conf (Sofia, Bulgaria, 7/6-7/12), 1997. 

T.D. Dimitrova and F. Leal Calderon Rheological Properties of Highly Concentrated Protein-Stabilized Emulsions. Adv. Colloid Interface Sci. 108-109, 49 (2004). 

Smith,T.L Bruce, C.A. (1979) Intrinsic viscosities and other rheological properties of flocculated suspensions of non magnetic and magnetic ferric oxides. J. Colloid Interface Sci. 72 13-25... 

It is also important to emphasize that conventional consciousness of colloid or fine particle technology, like better dispersion and control of rheological properties of dipping solution, are not to be overlooked. The growth of nanoparticles in liquid phase is almost exactly regulated by the nuclei-growth theory as well as stability of lyophobic colloids suggested half a century ago. 

Bos, M.A., van Vliet, T. (2001). Interfacial rheological properties of adsorbed protein layers and surfactants. Advances in Colloid and Interface Science, 91, 437-471. 

The term food colloids can be applied to all edible multi-phase systems such as foams, gels, dispersions and emulsions. Therefore, most manufactured foodstuffs can be classified as food colloids, and some natural ones also (notably milk). One of the key features of such systems is that they require the addition of a combination of surface-active molecules and thickeners for control of their texture and shelf-life. To achieve the requirements of consumers and food technologists, various combinations of proteins and polysaccharides are routinely used. The structures formed by these biopolymers in the bulk aqueous phase and at the surface of droplets and bubbles determine the long-term stability and rheological properties of food colloids. These structures are determined by the nature of the various kinds of biopolymer-biopolymer interactions, as well as by the interactions of the biopolymers with other food ingredients such as low-molecular-weight surfactants (emulsifiers). 

Jenkinson IR (1993) Bulk-phase viscoelastic properties of seawater. Oceanol Acta, 16 317-334 Jenkinson IR, Biddanda BA (1995) Bulk-phase viscoelastic properties of seawater relationship with plankton components. J Plankton Res 17 2251-2274 Jenkinson IR, Wyatt T, Malej T (1998) How viscoelastic effects of colloidal biopolymers modify rheological properties of seawater. In Emri I, Cvelbar R (eds) Proceedings of the 5th European Rheology Conference, Portoroz, Slovenia, September 6-11, 1998, Progress and Trends in Rheology 5 57-58... 

Mkuherjee, P. and Lahiri, A. Studies on the rheological properties of humic acid from coal, Colloid Sci. 11. 240-243 (1956). 

Saunders, F. L. 1961. Rheological properties of monodisperse latex systems I. Concentration dependence of relative viscosity. J. Colloid Sci 16 13-22. 

In this chapter, we review the rheological properties of suspensions of solids in a liquid medium, under conditions in which the particles do not clump together— that is, do not gel. Gelled colloidal suspension are discussed in Chapter 7, while emulsions md foams—where the suspended phase is another liquid or a gas—are discussed in Chapter 9. Even within these limits, the scope of this chapter is extensive, and there is only room for major topics. Additional detail can be found in Russel et al. (1989), Hiemenz and Rajagopalan (1997), Kim and Karrila (1991), and Chapter 10 of Macosko (1994). For reviews of the most recent work, see Brady (1996) and Mellema (1997). 

M. Joly, Rheological Properties of Monomolecular Films, in Surface and Colloid Science, E. Matljevic, M., Vol. 5 Wiley (1972), Part I Basic Concepts and Experimental Methods, p. 1 Part II Experimental Results. Theoretical Interpretation, Applications, p. 79. (Extensive review with several illustrations further reading to secs. 3.6 and 3.7e.)... 

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