Basf Aktiengesellschaft

Markus Koppers

Joachim Pakusch

Heinrich Sack

Marco Schmidt

Hans-J&uuml;rgen Denu

Eckehardt Wistuba

Juergen Schmidt-Thuemmes

Wolfgang Gaschler

Hans-Juergen Denu

J&uuml;rgen Schmidt-Th&uuml;mmes

Rolf Gulden

Mario Sandor

Hermann Anders

Thomas Anselmann

Mike Zott

A process for preparing a polymer powder by evaporating the volatile constituents from an aqueous dispersion of a film-forming polymer P, wherein prior to the evaporation of the volatile constituents the aqueous polymer dispersion still comprises drying assistants T, present in an amount of from 0.1 to 80% by weight, based on the polymer P of the dispersion, and there being used as drying assistant T polyvinylformamide. The polyvinylformamide used preferably has a K value (KW), determined by the method of Fikentscher in accordance with DIN 53726, of from 5 to 50.

Preparation of polymer powders

Polymer dispersions as an additive in building materials

Aqueous polymer dispersion and its use as a water-vapor barrier

The present invention provides a process for preparing polymer powders by evaporating the volatile constituents from aqueous dispersions of film-forming polymers P in the presence of drying assistants T selected from the salts of oligomeric arylsulfonic acid-formaldehyde condensates wherein prior to the evaporation of the volatile constituents the aqueous polymer dispersion comprises at least 1.5% by weight, preferably at least 1.7% by weight, based on the polymer in the dispersion, of at least one anionic surface-active compound AO having at least one C -C alkyl group; the polymer powders obtainable by the process; and their use in binding mineral building materials.

Growing community of inventors

Maxdorf, Germany

Markus Koppers