Process for the preparation of bead-form polymers

摘要

A process for the preparation of bead-form polymers from water-soluble, ethylenically unsaturated monomers by the process of reverse suspension polymerisation, in which an aqueous solution of the monomers is suspended in an inert hydrophobic liquid, and 2,2'-azobis(2-amidinopropane) dihydrochloride and/or 2,2'-azobis(N,N'-dimethyleneisobutyramidine) dihydrochloride as polymerisation initiator and formic acid or water-soluble salts thereof are polymerised therein in the presence of a protective colloid to give bead-form polymers. Polymer beads which are virtually agglomerate-free and have a low residual monomer content are obtained.