Rheology concentration effects

Lopata, V.J., Chung, M., Janke, C.J. and Havens, S.J., Electron curing of epoxy resins initiator and concentration effects on curing dose and rheological properties. 28th Int. SAMPE Technical Conference, 901, 1996. 

Yoo, B. and Rao, M. A. 1996. Creep and dynamic rheological behavior of tomato concentrates effect of concentration and finisher screen size. J. Texture Stud. 27 451-459. 

Concentration effects and interparticle forees are of rheological significance with injection molding mixes. Increasing the filler concentration (volume fraction) of a suspension increases the suspension relative viscosity tir = T)/rio, where ri is the suspension viscosity and Tjo is the continuous-phase viscosity. 

The intrinsic viscosity discussed in Section 11.3.1 is, strictly speaking, an infinite dilution value. To account for increasing solution viscosity with increasing concentration, an expansion in powers of concentration is usually used, as is also done to account for concentration effects in suspension rheology ... 

This formula may be useful as a rheological method for determining the thickness of adsorption layer, which is formed as a result of interaction between a dispersion medium and filler, by the results of measuring the t] versus q> dependence. Especially curious phenomena, connected with surface effects, arise when a mixture of fillers of different nature is used according to concentration of an active filler the introduction of the second (inert) filler can either increase or decrease the viscosity of a multicomponent system [35],... 

Because concentrated flocculated suspensions generally have high apparent viscosities at the shear rates existing in pipelines, they are frequently transported under laminar flow conditions. Pressure drops are then readily calculated from their rheology, as described in Chapter 3. When the flow is turbulent, the pressure drop is difficult to predict accurately and will generally be somewhat less than that calculated assuming Newtonian behaviour. As the Reynolds number becomes greater, the effects of non-Newtonian behaviour become... 

Electrolyte Effect on Polymer Solution Rheology. As salt concentration in an aqueous poly(1-amidoethylene) solution increases, the resulting brine becomes a more Theta-solvent for the polymer and the polymer coil compresses(47) This effect is particularly pronounced for partially hydrolyzed poly(l-amidoethylene). The... 

The results of these tests and the fluid formulations axe shown in Table IV. The adverse effect on fluid rheology of adding potassium, KC1, Test B, and TKPP, Test C, is evident. Both salts cause increases in yield point, YP, and initial gel strength. TKPP produced only about half as much increase as did KC1 and can be added in much higher concentrations before the rheological properties of the drilling mud become unacceptable. 

The rheological properties of a fluid interface may be characterized by four parameters surface shear viscosity and elasticity, and surface dilational viscosity and elasticity. When polymer monolayers are present at such interfaces, viscoelastic behavior has been observed (1,2), but theoretical progress has been slow. The adsorption of amphiphilic polymers at the interface in liquid emulsions stabilizes the particles mainly through osmotic pressure developed upon close approach. This has become known as steric stabilization (3,4.5). In this paper, the dynamic behavior of amphiphilic, hydrophobically modified hydroxyethyl celluloses (HM-HEC), was studied. In previous studies HM-HEC s were found to greatly reduce liquid/liquid interfacial tensions even at very low polymer concentrations, and were extremely effective emulsifiers for organic liquids in water (6). 

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