Effect of Adsorbed Polyethylene Oxide on the Rheology of Colloidal Silica Suspensions

Rheology of aqueous carbon black dispersions

“…Many factors contribute to the flow behavior of the system, but most importantly, the size, shape, and concentration of the dispersed particles, coupled to the dispersion stability, are known to be the flow-determining factors. Experiments conducted with spherical particles, sterically stabilized with grafted polymers, have shown that large particles behave similarly to hard spheres [5][6][7][8]. Through optical and rheological measurements on near hard-sphere suspensions of silica particles, it was concluded that the characteristic shear thinning in concentrated dispersions is due to changes in the thermodynamic contribution to the stress tensor while the hydrodynamic contribution remains relatively constant [9].…”

Interaction of poly(ethylene oxide) with fumed silica

“…According to Esumi et al [13], the interaction of PEO (10, 100, and 600 kDa) with slightly porous silica (S BET = 17.6 m 2 /g and particle size 0.7 µm) gives a low plateau adsorption (7.5-13 PEO mg per gram of silica). Comparative investigations of the interaction of PEO and related polymers with hydrophilic and hydrophobic silicas have been published [14][15][16][17], as well as the interaction of PEO with other materials. For instance, PEO (2.5 MDa) forms a layer up to 14 nm in thickness at a kaolinite surface and this interaction is characterized by a significant affinity of PEO to kaolinite as changes in the free energy G ads ≈ −14 kJ/mol [18].…”

Nanoparticle-laden tubeless and open siphons

“…Zaman et al (1996Zaman et al ( , 2000 treated the effects of absorbed PEO on the rheology of colloidal silica suspensions of particles on the order of 1 µm in concentrations up to 60% by volume. Their rheological studies focused on the shear viscosity.…”