What are physical and chemical stability in a dispersion?

In a dispersion, physical stability refers to the ability to maintain its physical properties, including particle size, viscosity, and appearance. Chemical stability refers to the ability to resist chemical reactions that may cause degradation or formation of unwanted substances. A stability analyzer can be applied to measure the physical stability of a dispersion, which is affected by inter-particle force, density, particle size and distribution, and temperature. When the dispersion is physically unstable, destabilization processes that are caused by particle migration and variation of particle size will progress.