Loading patent…
AssigneeDow Global Technologies LLC
InventorsEtienne Lazarus, Gerold Lohmüller, Juergen Dombrowski, Hartmut Kuehn, Margarita Perello, Sonja Scharlemann
Estimating the term…
A water redispersible polymer powder is produced by drying an aqueous mixture of a carboxylated styrene butadiene polymer and a colloidal stabilizer which includes a polyvinyl alcohol modified with an alkyl end chain. The alkyl modified polyvinyl alcohol provides excellent redispersibility of the redispersible polymer powder without adversely affecting spray drying. Cement compositions such as mortars, which contain the redispersible polymer powder with the alkyl modified polyvinyl alcohol exhibit unexpectedly superior stability and an unexpectedly lower rate of mortar viscosity buildup which is advantageous for workability or troweling.
A water redispersible polymer powder (RDP) composition comprising an admixture of a water insoluble film-forming polymer which is carboxylated and from 2% by weight to 20% by weight, based upon the weight of the water insoluble film-forming polymer of a colloidal stabilizer, said film forming polymer comprising a carboxylated styrene-butadiene copolymer, and said colloidal stabilizer comprising a combination of a polyvinyl alcohol having an alkyl end chain of from 6 carbon atoms to 20 carbon atoms (alkyl modified polyvinyl alcohol) and an unmodified polyvinyl alcohol wherein the amount of the alkyl modified polyvinyl alcohol is from 5% by weight to 70% by weight based on the weight of the colloidal stabilizer,
A method for producing a water redispersible polymer powder composition comprising drying an aqueous mixture of a water insoluble film-forming polymer and from 2% by weight to 20% by weight, based upon the weight of the water insoluble film-forming polymer of a colloidal stabilizer to obtain a water redispersible polymer powder, wherein the film forming polymer is carboxylated and comprises a carboxylated styrene-butadiene copolymer, and the colloidal stabilizer comprises a combination of a polyvinyl alcohol having an alkyl end chain of from 6 carbon atoms to 20 carbon atoms (alkyl modified polyvinyl alcohol) and an unmodified polyvinyl alcohol wherein the amount of the alkyl modified polyvinyl alcohol is from 5% by weight to 70% by weight based on the weight of the colloidal stabilizer.
Dependencies are inferred from the claim text.