摘要 |
A process for reducing the amount of residual monomer in aqueous polymer dispersions operates by aftertreatment with an initiator system essentially comprisinga) from 0.001 to 5% by weight, based on the total monomer amount used to prepare the polymer dispersion,a1) of an oxidizing agent where R1 is hydrogen or a C1-C8-alkyl or a C6-C12-aryl group, and/ora2) of a compound which in aqueous medium releases hydrogen peroxide, andb) from 0.005 to 5% by weight, based on the total monomer amount used to prepare the polymer dispersion,b1) of an alpha-hydroxycarbonyl compound where R2 and R3 independently of one another are hydrogen and/or a C1-C12-alkyl group which may contain functional groups and/or may be olefinically unsaturated, or R2 and R3 optionally, by way of methylene groups, form a ring structure which may contain functional groups and/or may be olefinically unsaturated, and/orb2) of a compound which in aqueous medium releases such alpha-hydroxycarbonyl compounds, andc) advantageously, catalytic amounts of a polyvalent metal ion which is able to exist in a plurality of valence states.
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