Question

Equipment used in structured breakdown of thixotropy

• A. Viscometer
• B. Planimeters
• C. Rotameters
• D. Orifice meter

Hint:

Thixotropy is essential in pharmaceutical formulations like suspensions and gels, ensuring ease of application during use and stability at rest.

Answer 1

The Correct Option is A

Thixotropy is a time-dependent shear-thinning property. A thixotropic material becomes less viscous over time when shear is applied and recovers its viscosity when the shear is removed. - This behavior is common in colloidal systems, gels, and suspensions, where structural breakdown occurs under stress and rebuilds when at rest.
- A viscometer is an instrument used to measure the viscosity of a fluid. In the study of thixotropy, viscometers help observe how viscosity decreases over time under constant shear—indicating structural breakdown.
- Brookfield viscometer and rotational viscometers are widely used for studying thixotropic flow behavior in pharmaceuticals.
Other options: - Planimeters (option b) are used to measure the area on a two-dimensional plane and are not relevant to rheology.
- Rotameters (option c) measure fluid flow rate, not viscosity.
- Orifice meters (option d) are also flow-measuring devices used in process industries.
Hence, the correct equipment for measuring the structural breakdown in thixotropy is the viscometer.