Characterising the Progress of Dispersion

1 Measurands Frequently Used for Characterising the Progress of Dispersion 

Studies on the mechanisms and efficiency of dispersion processes are usually conducted under well-defined conditions, which eases sampling and sample preparation. Frequently, the most appropriate characterisation techniques can be 

Some applications require not only a general reduction of particle size, but additionally a limitation of the maximum particle size or the concentration of coarse particles—e.g. pigment dispersion (Ruscitti et al. 2008) or preparation of CMP slurries (e.g. Kuntzsch et al. 2003). These parameters can be measured by special instruments (grindometer, ISO 1524) or by counting methods (e.g. optical particle counting, cf. Xu 2000, pp. 182-222). 

This brief review on the practice of dispersion monitoring— from scientific publications only— has mentioned several measurands and various characterisation techniques. It is very likely that they show different capabilities to reflect changes in size distribution and that these capabilities depend on the particle system involved. However, the scientific literature is rather sparse on studies that thoroughly examine the performance of characterisation teclmiques. There is no data basis for a general evaluation instead, selected examples with a focus on pyrogenic powders are presented below. 

2 Dispersion Monitoring for Suspensions of Pyrr enic Powders 

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