Rheology is a key characterization technique for developing materials with the desired physical properties and for controlling the manufacturing process in order to ensure product quality. Rheology is very sensitive to small changes of the material’s polymer structure – thus ideal for characterization of polymers.
What is a rheological agent? Rheological agents are multi-functional, ubiquitous ingredients found in most formulations that can significantly impact stability and performance. … Learning how to choose the correct technology for your formulation can dramatically improve in use product performance and stability.
Similarly, Why is rheology important in pharmacy? Drug Formulation and Process Development
Rheological characterization tools, such as viscometers, allow drug producers to directly affect how a drug is formulated and developed, cutting across parameters and conditions to arrive at product characteristics that can be quantified.
Is viscosity a rheological property?
The rheological parameters were viscosity (cp), torque%, shear stress (dyne/cm2) and shear rate (s–1).
What is the relationship between rheology and viscosity?
These two terms are related to fluids such as liquids and gases. The key difference between rheology and viscosity is that rheology is the study of the flow of matter whereas viscosity is a measure of its resistance to deformation.
What are rheological properties of fluids?
Rheological properties refer to the Bingham plastic fluid parameters such as yield point (YP) and plastic viscosity (PV). It is one of the several flow characteristics of drilling fluid, workover fluid or completion fluid or cement.
What are the examples of rheology? Many physiological materials and fluids exhibit complicated rheology. Within the eye, examples include the vitreous humour, the liquid in the tear film, and the blood in capillaries.
What instrument determines rheological properties of suspension? A rheometer is a laboratory device used to measure the way in which a liquid, suspension or slurry flows in response to applied forces. It is used for those fluids which cannot be defined by a single value of viscosity and therefore require more parameters to be set and measured than is the case for a viscometer.
What are the applications of rheology?
Applications. Rheology has applications in materials science, engineering, geophysics, physiology, human biology and pharmaceutics. Materials science is utilized in the production of many industrially important substances, such as cement, paint, and chocolate, which have complex flow characteristics.
What is plastic flow in rheology? Plastic flow is a rheological phenomenon in which flowing behavior of the material occurs after the applied stress reaches a critical value (yield).
What rheological behavior is most suitable for pharmaceutical suspensions?
A vehicle used for the preparation of pharmaceutical oral suspensions preferably shows pseudo-plastic behavior. In a product that gets thinner with agitation and thicker upon standing, slow settlement of the suspended active pharmaceutical ingredient is combined with good pourability and rehomogenization.
Which property is not a rheological property?
| Q. | Which one of the following physical Property is NOT a rheological property? |
|---|---|
| B. | spreadability |
| C. | surface tension |
| D. | viscosity |
| Answer» c. surface tension |
What is a rheological fluid?
10.6 Fluid Rheology
Rheology is the science of fluid flow and deformation. Fracturing fluids are non-Newtonian fluids, meaning their rheology is viscous in nature and varies based on applied stress.
What is rheology in physical pharmacy?
Definition of Rheology • Rheology is the science/physics that concerns with the flow of liquids and the deformation of solids. • Study of flow properties of liquids is important for pharmacist working in the manufacture of several dosage forms, viz., simple liquids, gels, ointments, creams, and pastes.
What are rheological models? Rheology is the study of mechanical properties and flow of matter, specifically non-Newtonian fluids, mixtures, and plastic solids.
What is the rheological meaning?
: a science dealing with the deformation and flow of matter also : the ability to flow or be deformed.
What are rheological properties of asphalt?
The aging properties of asphalt binders are normally characterized by measuring physical and rheological properties (e.g. softening point, penetration, viscosity and complex modulus) before and after artificial aging in the laboratory.
What are Newtonian and non-Newtonian fluids? Newtonian fluids obey Newton’s law of viscosity. The viscosity is independent of the shear rate. Non-Newtonian fluids do not follow Newton’s law and, thus, their viscosity (ratio of shear stress to shear rate) is not constant and is dependent on the shear rate.
What does the word rheological mean?
Definition of rheology
: a science dealing with the deformation and flow of matter also : the ability to flow or be deformed.
What do you understand by rheology? Rheology is the science of measurement of deformation. Virtually all materials deform in response to an imposed stress (‘everything breaks if you hit it hard enough’) and the materials present in the eye range from liquid-like to soft-solid behaviour.
What are the rheological layers of the earth?
If we subdivide the Earth based on rheology, we see the lithosphere, asthenosphere, mesosphere, outer core, and inner core. However, if we differentiate the layers based on chemical variations, we lump the layers into crust, mantle, outer core, and inner core.
How do you measure rheological properties? To measure the rheological properties of a material, rheometers are used. They measure the torque and the deflection angle of the measuring bob. This means that in a viscosity measurement the rheometer presets a certain current that correlates to a defined torque.