| abstract |
Water-soluble polymers having high molecular weight with little branching and good water solubility, particularly acrylamide series polymers having excellent flocculation effect can be obtained when 2,2'-azobis-(N,N'-dimethyleneisobutylamidine) or an acid addition salt thereof or a mixture of 2,2'-azobis(N,N'-dimethyleneisobutylamidine) or an acid addition salt thereof and another azo compound is used as polymerization initiator. |