Rheology thixotropic

As substituent uniformity is increased, either by choosing appropriate reaction conditions or by reaction to high degrees of substitution, thixotropic behavior decreases. CMCs of DS >1.0 generally exhibit pseudoplastic rather than thixotropic rheology. Pseudoplastic solutions also decrease in viscosity under shear but recover instantaneously after the shear stress is removed. A plot of shear rate versus shear stress does not show a hysteresis loop. 

Fermented milk products exhibit thixotropic rheological properties, i.e. the viscosity (resistance to flow) decreases as the rate of shear increases a typical relationship is shown in Figure 10.33. The rheological properties are major parameters of quality and are controlled by varying the total solids content of the milk, the heat treatment and homogenization of the milk and the use of hydrocolloids, e.g. gelatin or carageenan. 

Settling. Separation of paint in a container in which the pigments and other dense insoluble materials accumulate and aggregate at the bottom. The law of gravity applies to paint, as does Stokes law. An increase in consistency will help, as will a thixotropic rheology. Various additives are available to do this. 

The thixotropic rheological behavior of structured disperse system to a significant extent depends on the direction towards which the equilibrium between rupture and re-establishment of interparticle contacts is shifted. Because of the finite rate of contact formation due to Brownian motion, a certain amount of time is needed for the equilibrium to establish. Consequently, some time is required for a spontaneous thixotropic restoration of structure destroyed by mechanical action. Due to a complete structure disintegration taking place in region IV (Fig. IX-24), the strength, i.e. the... 

This same characteristic explains why carrageenin can be used so effectively in stabilizing suspensions. Perfect suspension requires infinite viscosity at zero rate of shear between particle and liquid under normal gravitational forces. Or, expressed in another way, the yield value of the system is greater than the mass of any of the particles being suspended. This characteristic of thixotropic rheology apparently exists in all effective systems. 

Chem. Descrip. Amorphous syn. silica CAS 112926-00-8 EINECS/ELINCS 231-545-4 Uses Thixotrope, rheology modifier, antisagging agent, suspending agent in coatings, resins, sealants, and adhesives Properties 2 median particle size dens. 2 Ib/tf Hisolve DM [Toho Chem. Ind.]... 

Ferres Heat-activated easy to disperse provides more low shear thixotropic rheology than conventional orqanoclays or other self-activating organoclays... 

In polymer nanocomposites, there are two common indirect methods. The first is the measurement of melt viscosity. In this method a rheometer is normally utilized where the viscosity can be measured as a function of shear rate. Clay nanoparticles normally impart thixotropic rheology to the nanocomposite melt. In this type of rheology the melt viscosity at low shear will be much higher than the pure... 

Polyvinyl alcohol Fabric supported gloves Solutions of PvOH can be difficult to prepare. PvOH usually gives a thixotropic rheology. 

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