A process for fractionating water-soluble or water-dispersible
amino-containing synthetic polymers having a broad molar mass distribution
by ultrafiltration, wherein the polymer solution or dispersion to be
fractionated is fed continuously into an ultrafiltration circulation with
at least one ultrafiltration unit, and retentate having a narrower molar
mass distribution and permeate are discharged continuously, in such a way
that the ultrafiltration circulation is essentially in a steady state, the
polymers obtainable by this process and their use.
