Newtonian liquids, microrheology

The microrheology of Newtonian liquids has been summarized by Goldsmith and Mason and by Grace (3 3). That of polymeric melts Is in its infancy (37). 

The microrheology makes it possible to expect that (i) The drop size is influenced by the following variables viscosity and elasticity ratios, dynamic interfacial tension coefficient, critical capillarity number, composition, flow field type, and flow field intensity (ii) In Newtonian liquid systems subjected to a simple shear field, the drop breaks the easiest when the viscosity ratio falls within the range 0.3 < A- < 1.5, while drops having A- > 3.8 can not be broken in shear (iii) The droplet breakup is easier in elongational flow fields than in shear flow fields the relative efficiency of the elongational field dramatically increases for large values of A, > 1 (iv) Drop deformation and breakup in viscoelastic systems seems to be more difficult than that observed for Newtonian systems (v) When the concentration of the minor phase exceeds a critical value, ( ) >( ) = 0.005, the effect of coalescence must be taken into account (vi) Even when the theoretical predictions of droplet deformation and breakup... 

Based on microrheology, it is possible to expect that (i) the drop size is influenced by the following variables viscosity and elasticity ratios, dynamic interfacial tension coefficient, critical capillary number, composition, flow field type, and flow field intensity (ii) in Newtonian liquid systems subjected to a simple shear field, the drop breaks most easily when the viscosity ratio falls within the... 

The orientation of particles in flow is of particular interest to microrheology. To predict the macroscopic rheological properties of a multiphase system, a detailed description of each phase behavior is required. In this field, contributions from the Pulp and Paper Research Institute of Canada by Mason et al. and later by van de Ven and his coauthors are particularly valuable. The earlier results were summarized by Goldsmith and Mason (1967), the latter by Van de Ven (1989). The microrheology has been particularly well developed for infinitely dilute systems in Newtonian matrix - either solid particles or liquid drops. In the present part, only the former system will be summarized. More extensive discussion of microrheology of the liquid-liquid systems will be presented later, while considering the rheological behavior of polymer blends. 

Clearly, the microrheology of polymeric systems is more complex than the classical microrheology of Newtonian, low viscosity liquids. Near the liquefaction point (either T or Tg) the viscosity is of the order of lO Pas, and the relaxation time is of the order of 100 s (Angell 1997). As temperature... 

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