92168.pdf

252 Rheology viscosity and relative molecular mass can be expressed by the general equation proposed by Mark and Houwink: to] = ...

Rheology 253 If particle aggregation occurs in a colloidal system, then an increase in the shear rate will tend to break down th ...

254 Rheology Many colloidal systems exhibit so-called Bingham flow, which is characterised by the equation a - o-B = rjD (9.7) P ...

Rheology 255 Shear stress, a Figure 9,5 A thixotropic loop 9.5) can be obtained by measuring the non-equilibrium shear stress as ...

256 Rheology Work-hardening can occur as a result of mechanical entanglement or jamming of the structural elements on shearing, ...

Rheology 257 where an arbitrary number which bears some relation to the mechanical property under consideration is usually quite ...

258 Rheology For Hookean elastic solids the stress and strain are in phase, whereas for purely viscous liquids the strain lags 9 ...

The time taken for the structural units in viscoelastic materials, such as high polymers, to flow into new positions relative to ...

260 Rheology Owing to the thermal nature of the restoring force, the deformation of rubber, for a given load, decreases as the t ...

Rheology 261 another without weakening the material, the forces (specific and non- specific) between them must be overcome and t ...

Oil-in-water and water-in-oil emulsions 123 " 126 An emulsion is a dispersed system in which the phases are immiscible or partia ...

Emulsions and foams 263 with large droplets, through blue-white, then gray-translucent, to transparent, with small microemulsion ...

264 Emulsions and foams determining droplet size distributions in O/W emulsions. In this method a dilute dispersion is made to f ...

Emulsions and foams 26.5 the development and enhancing the stability of the large interfacial areas associated with emulsions. ...

266 Emulsions and foams eventually break. Emulsions with a fairly uniform droplet size will be less prone to this effect. High ...

Emulsions and foams 267 (bj I H" Io7( ~—"— Figure 10.1 Stabilisation of emulsions by finely divided solids: (a) preferential wet ...

268 Emulsions and foams formation of this particular O/W emulsion by use of other emulsifier systems; for example, the optimum p ...

Emulsions and foams 269 Breaking of emulsions In many instances it is the breaking of an emulsion (demulsification) which is of ...

270 Emulsions and foams With yOw close to zero, microemulsions will form spontaneously and are thermodynamically stable. The dro ...

Emulsions and foams 271 liquid drainage, or directly from a liquid of relatively low viscosity)*. The nature of thin liquid film ...