The downside of dispersity: why the standard deviation is a better measure of dispersion in precision polymerization†
Dispersity is firmly established as the standard measure of dispersion in molecular weight distributions. However, it can be misleading, particularly when applied to the relatively narrow molecular weight distributions obtained via living or reversible deactivation polymerizations. The use of the standard deviation is recommended as an alternative. In complex structures, a representative sample of chains provides a better illustration of structural variation than any single number.