What are thixotropic agents?
What are thixotropic agents?
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 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 paste?
Thixotropic adhesives generally refer to thick paste-like adhesives whose viscosities can be changed when shaken, agitated or otherwise stressed. The viscous nature of our adhesives can be modified through the use of fillers and regulation of the curing temperature to best suit your application needs.
What is thixotropic index?
The thixotropic index is a ratio of the viscosity of a material at two different shear rates (low-shear viscosity/high-shear viscosity). The low-shear rate and high-shear rate are typically different by a factor of 10.
How does a thixotropy work?
‘Thixotropy’ is shear thinning property; when an alloy is sheared it thins, but when it is allowed to stand it thickens again. This behavior is associated with the breakup of agglomerates of solid particles under shear and their reformation when the shear is removed.
What are the pharmaceutical applications of thixotropy?
The time-dependent change in viscous nature of thixotropy finds its major applications in pharmaceutical formulations including hydrogel, ointment, suspensions and emulsions through various routes including oral, topical, ophthalmic and mucosal administration, as shown in Table 2.
What is thixotropy manufacturing?
What is thixotropy and how does it influence the manufacturing of paint and related products? Thixotropy is a property of some products which change their viscosity and become more fluid when subject to constant shear force, e.g., in the mixing stage. The longer the fluid is under shear stress, the less its viscosity.
How thixotropy is measured?
Thixotropy can be quantitatively measured using a rotational rheometer. The most commonly used testing geometries are 20-40 mm parallel plate or a cup/rotor geometry.
What is thixotropy and Antithixotropy?
The term anti-thixotropy is used when the apparent viscosity is an increasing function of the duration of flow and when, as with thixotropy, the body recovers its initial state after a long enough rest.
What is thixotropy in chemistry?
Thixotropy has been proposed as a scientific explanation of blood liquefaction miracles such as that of Saint Januarius in Naples. Semi-solid casting processes such as thixomoulding use the thixotropic property of some alloys (mostly light metals like magnesium).
What is thixotropic casting?
Thixotropic casting is the only method by which a 1 m-square (or larger) ceramic can be “wet-formed” without cracking because of the near-zero drying shrinkage. Ordinarily a 1 m-square tile can only be fabricated by uniaxial die pressing at around 4000 t, is very fragile in the green state, and the cost of a 4000 + ton press is prohibitive.
What is thixotropic breakdown coefficient?
The “thixotropic breakdown (Tb) coefficient” is a simple test for analyzing the time-dependent behavior of samples. It is especially used for quick quality control checks with entry-level rotational viscometers.
Which of the following is an example of thixotropic material?
Examples of thixotropic materials are lotions, gels, ketchup, paints, and gypsum. For example, ketchup flows out of the tube when it is pressed. Its viscosity becomes lower as force is applied. After the force lessens, the viscosity of the ketchup recovers to its initial state for perfect leveling on French fries.