Aqueous dispersion of water-soluble polymer composition

A process for producing an aqueous dispersion, having good stability and fluidity, of water-soluble polymers, which comprises polymerizing or copolymerizing (a) the monomer components of a composition containing at least one water-soluble ethylenically unsaturated monomer, all of said monomer components in said composition being capable of being polymerized or copolymerized with each other to form only a water-soluble polymer or copolymer, said polymerization being carried out in an aqueous solution of (b) at least one water-soluble polymer which is different from the polymer derived from said monomer components (a), said aqueous solution containing 3 to 150 parts by weight of said water-soluble polymer (b) per 100 parts by weight of water, the amount of said monomer components (a) being 10 to 150 parts by weight per 100 parts by weight of said water, the weight ratio of (a):(b) being within the range of from 1:5 to 5:1, said aqueous dispersion of water-soluble polymers being (i) a dispersion in water of a loose water-containing complex composed of said polymer or copolymer derived from said monomer components (a) and said water-soluble polymer (b), or (ii) a dispersion of said polymer or copolymer derived from said monomer components (a) in said aqueous solution of said water-soluble polymer (b).