To obtain the subject polymer dispersant high in polymer volume concentration and reduced fine flocculate content by emulsifying a monomer in the aqueous dispersant for initiation polymer(s) followed by-continuously feeding the polymerization system with the resultant emulsion.
An ethylene-based unsaturated monomer, except vinyl halides and vinylidene halides, is subjected to radical emulsion polymerization in the presence of (A) at least one kind of initiator and (B) at least one kind of initiation polymer to obtain the objective low-viscosity aqueous polymer dispersant 250vol.% in polymer volume concentration. In this case, a large proportion of the monomer is emulsified in the aqueous dispersant for the component B, and the resultant emulsion is continuously fed to the polymerization system. It is preferable that the amount of the component B to be used is 0.01-10wt.% based on the monomer to be used and the average particle diameter of the component B is <250nm.
SCHULER BERNHARD DR
STANGER BERND DR
