What is powder rheology?
Powder rheology is the study of the behaviour of powders as bulk assemblies, consisting of solids, liquids and gases. It allows users to measure the dynamic flow and shear properties of powders as well as quantifying bulk properties such as density, compressibility and permeability.
What are the flow properties of powder?
Few such flow properties and techniques are powder spreadability, dynamic and static angle of repose, packing, flowability, and electrostatic charge.
What is the importance of micromeritics?
5. Micromeritics • Micromeritics is the science and technology of small particles. Knowledge and control of the size and the size range of particles are of significant importance in pharmacy because the size and surface area of a particle related to the physical, chemical and pharmacologic properties of a drug.
What is porosity of powder?
Porosity is defined as the ratio of the total pore volume to the apparent volume of the particle or powder (excluding interparticle voids).
What are types of powder?
Q: Types of Powder
- Types of powders.
- Loose powders.
- Pressed Powder. A pressed powder is ideal for a gal on the go or someone who wants a bit more precision and a wider shade range.
- Translucent Powder.
- Coloured Powders.
- Setting powder.
- Finishing powder.
- Color Correcting Powders.
How do you test the viscosity of powder?
A method is described for determining the effective viscosity of powder com- pacts during densification as a function of temperature. The method utilizes constant rate of heating and is easily adapted to determining the sintering temperature of a powder compact as well as measuring the effective viscosity.
How does particle size affect powder flow?
Smallness of the particle size of the powder could tend to reduce powder flow due to the increase surface area per unit mass has provided a greater surface area for surface cohesive forces to interact resulting in more cohesive flow.
How do you increase powder flow?
Granulators. Granulation is a common technique to help to improve product flow and achieve mass flow. Powder granulation can reduce inconsistency in particle size, reduce “fines” (very small particles), control dust, and reduce the tendency of powders to segregate.
What is the significance of micromeritics in powder formulation development?
Micromeritic properties of a particle, i.e. the particle size in a formulation, influence the physical stability of the suspensions and emulsions. The smaller the size of the particle, the better the physical stability of the dosage form owing to the Brownian motion of the particles in the dispersion.
What is meant by Micromeritics?
Definition of micromeritics : a field of science that deals with small particles and that is applied especially in soil physics.
What is permeability and porosity?
Porosity: is a measure of the void spaces in a material. Permeability: a measure of the ability of a material (such as rocks) to transmit fluids. Porosity and permeability are related properties of any rock or loose sediment. Both are related to the number, size, and connections of openings in the rock.
How are the properties of Micromeritics related to product quality?
The product quality of tablets, capsules, suspensions and emulsions from the viewpoint of both uniformity and stability depends on the micromeritic properties such as particle size, shape, surface morphology, density and flowability.
What does rheology mean in relation to particle size?
Rheology: Maintaining a constant mass of particles in a suspension while reducing the particle size leads to increased number of particles. A higher number of smaller particles results in more particle-particle interactions and an increased resistance to flow.
How is the resistance of a powder measured?
The FT4 measures the resistance that a powder exerts on twisted blade, as it forces its way through the sample. This resistance is expressed as “Flow Energy”, calculated from direct measurements of torque and force.