AbstractA simple method has been suggested for the fractionation of polysuccinimide (PSI); the intrinsic viscosities of fractions were measured and the parameters of the Mark‐Houwink equation were determined. The possibilities of reactions of PSI with primary amines such as histamine, tyramine, tryptamine, mono‐BOC‐ethylenediamine, glycine nitroanilide, and ethanolamine were checked; the reaction rate constants and the effect of some catalysts were deter