Process for preparing water-redispersible polymer powders

A process for preparing protective colloid-stabilized polymers of ethylenically unsaturated monomers, comprising:

• admixing aqueous dispersions of protective colloid-stabilized polymers of ethylenically unsaturated monomers with one or more drying aids and then drying the mixture;
• wherein one or more salts of organic compounds containing 1 to 10 carbon atoms and optionally one or more protective colloids are used as drying aids;
• wherein the drying aids comprise ≥80% by weight, based on the total weight of the drying aids, of one or more salts of organic compounds containing 1 to 10 carbon atoms;
• wherein 0.1% to 20% by weight based on the dry weight of the aqueous dispersions of the protective colloid-stabilized polymers of salts of organic compounds containing 1 to 10 carbon atoms is used as drying aids;
• and
• wherein the one or more protective colloids are selected from the group comprising polyvinyl alcohols, polyvinylpyrrolidones, polysaccharides in water-soluble form, proteins, lignosulfonates, polyacrylic acid, polymethacrylic acid, copolymers of acrylates with carboxy-functional comonomer units, copolymers of methacrylates with carboxy-functional comonomer units, polyacrylamide, polymethacrylamide, polyvinylsulfonic acids and the water-soluble copolymers thereof, melamine-formaldehydesulfonates, naphthalene-formaldehydesulfonates, styrene-maleic acid copolymers and vinyl ether-maleic acid copolymers.