This article provides a fundamental understanding of the key particle characterization methods that are being used in academia and industry alike, and assumes no previous information of either instrumentation or particle characterization theory. The article is useful for those who are new to particle characterization or those who wish to strengthen their understanding about the field. It discusses introductory basics, particle characterization instrumentation, particle sizing theory, and also serves as a quick reference guide, so that users can decide which method is suitable for their particle characterization requirements. However, this article does not cover all particle characterization methods
What is a Particle?
A particle, at the most fundamental level, can be defined as a distinct, sub-portion of a substance. The definition is narrowed down to include gas bubbles, liquid droplets or solid particles with physical sizes spanning from sub-nanometer to a few millimeters in size.
Following are the most common types of materials containing particles:
- Granules and powders, such as cement, pigments, and pharmaceutical ingredients
- Sprays and aerosols like crop protection sprays and asthma inhalers
- Emulsions, suspensions, and slurries, such as milk, vaccines, and mining muds
Why Measure Particle Properties?
A large number of industries often use particle characterization methods. There are two major reasons for this:
Better Control of Product Quality
In today’s ever-increasing competitive economy, real economic benefits can be obtained through improved control of product quality. These benefits include:
- Charging a higher premium for a product
- Demonstrating compliance in regulated markets
- Reducing client’s rejection rates and the lost orders
Better Understanding of Products, Ingredients and Processes
In addition to controlling the quality of products, a deeper insight into particle properties and their effect on the processes, products, and ingredients will enable individuals to:
- Enhance the performance of a product
- Troubleshoot problems related to manufacturing and supply chain
- Improve the efficiency of the production processes
- Improve yield or increase output
- Stay ahead of the competition
Which Particle Properties Are Important to Measure?
The physical characteristics of the constituent particles usually control the behavior of particulate materials, in addition to chemical composition. These parameters can affect a variety of material properties, such as abrasivity, compressibility, speed of reaction and dissolution, and how effortlessly ingredients flow and combine together. With respect to production and development, the following physical properties have to be determined:
- Particle shape
- Particle size
- Mechanical properties
- Surface properties
- Charge properties
Some or all these properties may be critical based on the target material, and these may be even interrelated, e.g. particle size and surface area. Here, the focus is given to two of the most important properties that can be easily quantified: particle shape and particle size.
Other Areas Discussed in this Article
- Particle properties
- Particle size
- How do we define particle size?
- Particle size distributions
- Weighted distributions
- Number-weighted distributions
- Volume-weighted distributions
- Intensity-weighted distributions
- Distribution statistics
- Particle shape
- How do we define particle shape?
- Particle form
- Particle outline
- Universal shape parameters
- Zeta potential
- Particle characterization techniques
- Which particle characterization techniques do I need?
- Sample dispersion
- Wet dispersion
- Dry dispersion
- Techniques: Laser diffraction particle sizing
- Optical properties
- Techniques: Dynamic light scattering
- Techniques: Automated imaging
- Techniques: Electrophoretic light scattering (ELS)
- Particle-related properties: Rheology
This information has been sourced, reviewed and adapted from materials provided by Malvern Panalytical.
For more information on this source, please visit Malvern Panalytical.