| abstract |
The present invention relates to a polymerizate in the form of an aqueous polymer dispersion, the polymerizate being obtainable by radical polymerization of monomers in an aqueous medium in the presence of a free radical initiator and a protective colloid, wherein the monomers comprise a) 50-99.99 wt.% of at least one vinyl monomer chosen from the group of vinyl esters, (meth)acrylic esters, vinyl aromatic compounds, vinyl halides, and olefins, and b) 0.01 -30 wt.% of at least one macromonomer M, the macromonomer M being a reaction product of components (i), (ii), and (iii), said - component (i) having at least one olefinically unsaturated group and at least one hydroxyl, amine and/or thiol group, - component (ii) being a di- or triisocyanate, and - component (iii) having at least two terminal groups selected from hydroxyl, amine and/or thiol groups, c) 0-20 wt% of at least one vinyl monomer with at least one functional group, wherein the monomers a), b), and c) sum up to 100 wt.% of total monomers employed. The invention further provides a process to prepare the polymerizate, water-redispersible polymer powders obtainable from the polymerizate, and building material compositions containing the polymerizate and/or the water-redispersible polymer powders. |