What is thixotropic effect?
Thixotropy is a time-dependent shear thinning property. Certain gels or fluids that are thick or viscous under static conditions will flow (become thinner, less viscous) over time when shaken, agitated, shear-stressed, or otherwise stressed (time-dependent viscosity).
What is thixotropic behavior?
In rheology thixotropic behavior is defined as time-dependent behavior. It means a reduction of the structural strength during a constant shear load phase and a more or less rapid but complete regeneration of the structure during the subsequent rest phase.
How does thixotropy work?
Thixotropy is a rheological property whereby the viscosity of a liquid decreases when it is agitated, which is the opposite of dilatancy. Thixotropic casting involves the preparation of a highly thixotropic paste which, when vibrated, flows and can be cast into a mold, and in the absence of vibration is quite rigid.
How do you increase thixotropy?
An increase on thixotropy is observed as temperature decreases. From the hysteresis area, both viscosity and the degree of thixotropy gradually increase when the temperature decreases from 35 ºC to 5 ºC. The degree of thixotropy observed for the rest of paints was less dependent upon temperature.
What is the difference between pseudoplastic and thixotropic?
The key difference between thixotropic and pseudoplastic is that the viscosity of thixotropic fluids decreases upon applying a force, whereas the viscosity of pseudoplastic fluids increases upon applying a force. Some common examples of pseudoplastic fluids include ketchup, paint, cornstarch in water suspension, etc.
What is the example of thixotropic fluid?
Other examples of thixotropic fluids are gelatine, shortening, cream, xanthan gum solutions, aqueous iron oxide gels, pectin gels, hydrogenated castor oil, carbon black suspension in molten tire rubber, many floc suspensions, and many colloidal suspensions.
What is thixotropic gel used for?
Thixotropic gel forms a barrier between blood cells and serum or plasma, thus preventing contamination and allowing easy separation. Glycolysis is a cellular reaction used to harvest energy from glucose.
What is a thixotropic agent?
Thixotropic agents are added to oil-well cement slurries to produce thixotropic properties downhole, which are needed to overcome problems of lost circulation by sealing off lost circulation zones or achieving good annular fill across incompetent zones.
What is thixotropic flow?
A thixotropic fluid is one that takes a fixed time to return to its equilibrium viscosity when subjected to abrupt changes in shear rate. In other words, the liquid becomes less viscous (thinner or flows more easily) when shaken, stirred, agitated or otherwise stressed.
What is thixotropic and rheopectic fluid?
The key difference between thixotropic and rheopectic fluids is that in thixotropic fluids, the viscosity of the fluid decreases with stress over time whereas, in rheopectic fluids, the viscosity of the fluid increases with stress over time. Fluids are liquid or gaseous substances that have a viscosity.
Why is thixotropic important?
Thixotropy is important for applications that require the material to flow easily during dispensing but then must stay in place once they are dispensed. This allows materials to be dispensed in exact patterns and shapes without any sagging or slumping after application.
What is a thixotropic fluid?
What is thixotropy and how does it work?
Thixotropy is a time-dependent shear thinning property. Certain gels or fluids that are thick or viscous under static conditions will flow (become thinner, less viscous) over time when shaken, agitated, shear-stressed, or otherwise stressed ( time-dependent viscosity ). They then take a fixed time to return to a more viscous state.
What is thixotropy and how is it related to viscoelasticity?
If the changes are reversible and time dependent, the effect is called thixotropy. The basic elements of this concept are reviewed here, including its definition and the relation with nonlinear viscoelasticity. The omnipresence of thixotropy is illustrated with a wide range of examples from natural and manmade colloidal systems.
A thixotropic fluid is a fluid which takes a finite time to attain equilibrium viscosity when introduced to a steep change in shear rate. Some thixotropic fluids return to a gel state almost instantly, such as ketchup, and are called pseudoplastic fluids. Others such as yogurt take much longer and can become nearly solid.
What is microstructural model in thixotropy?
Microstructural models One of the ultimate goals in modeling thixotropy is the development of models that are based on an actual analysis of the physical phenomena underlying thixotropy. This requires a full description of the structure as it develops during arbitrary flow histories.