摘要 |
<p>An aqueous polymer composition is described comprising a homogeneous acrylic polymer dispersion produced by emulsion polymerization of a monomer mixture comprising: (A) from 85 to 99.9 wt%, based on the total weight of monomers in the mixture, of one or more main monomers selected from C 1 -C 12 -alkyl esters of acrylic acid or C 5 -C 12 -alkyl esters of methacrylic acid, styrene, and vinyl toluene in such a ratio as to produce a polymer having a Tg in the range of -20 to +65 °C; and (B) from 0.1 to 5 wt%, based on the total weight of monomers in the mixture, of at least one stabilising monomer selected from ethylenically unsaturated monocarboxylic acids or amides thereof, ethylenically unsaturated dicarboxylic acids or anhydrides or amides thereof, ethylenically unsaturated sulfonic acids, ethylenically unsaturated phosphoric acids, and ethylenically unsaturated phosphonic acids. The emulsion polymerization is conducted in the presence of 0.05 to 3 wt%, based on the total weight of monomers in the monomer mixture, of a chain transfer agent (C). Also described are an aqueous polymer composition comprising a heterogeneous acrylic polymer dispersion and an aqueous polymeric acrylic/alkyd hybrid dispersion useful in the formulation of high gloss paints.</p> |