| 摘要 |
Production of aqueous polymer dispersions containing relatively large polymer particles by polymerizing olefinically unsaturated monomers (A) and, if desired, olefinically unsaturated monomers (A') in aqueous emulsion in the presence of conventional dispersing agents, catalysts and previously prepared emulsion polymers of olefinically unsaturated monomers carried out by adding, during the polymerization of the monomers (A) and, if present, (A') up to a point where 95 percent of said monomers have been converted, minor quantities of previously prepared emulsion polymers in the form of an aqueous dispersion, which emulsion polymers contain from 0.5 to 50 percent of their weight of polymerized units of olefinically unsaturated monomers (B) which when polymerized alone yield water-soluble homopolymers, the proportion of monomers (A') in admixture with the monomers (A) being at least 20 percent (based on the proportion of polymerized units of monomers (B) in the previously prepared emulsion polymer) less than the proportion of polymerized units of the monomers (B) in the previously prepared emulsion polymer.
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