ABSTRACT
This relationship simplifies largely the real situation. In contrast to low molecular substances that have well-defined molecular masses, macromolecular substances do not have. Due to the statistical nature of polymerization processes, it is impossible to obtain polymer samples comprising macromolecules of identical size or chain length. Samples are produced that are non-uniform with respect to molecular mass. Therefore, polymers have molecular mass distributions and one characterizes the molecular mass of a polymer by suitable averages.
