Degussa Aktiengesellschaft

Evonik Degussa Gmbh

Bernd Bartkowiak

Burkhard Standke

Kerstin Weissenbach

Nadja Kempkes

Aqueous oil-in-water emulsion comprising from 1 to 70% by weight, based on the total weight of the emulsion, of functional alkoxysilanes and/or condensed oligomers thereof and/or organoalkoxysiloxanes, at least one emulsifier and water, wherein the emulsion has a pH of from 5 to 9 and preferably a mean droplet size of the disperse phase of &#x2266;0.5 &#x3bc;m, and the width of the droplet size distribution, expressed as the span (Formula I), is from 0.6 to 1.2. The preparation of the emulsions having the desired droplet size distribution is carried out in apparatuses having at least one pressure stage at a pressure of from 2 to 15 MPa. The emulsion can be used for hydrophobicizing porous mineral building materials.

Aqueous emulsions of functional alkoxysilanes and condensed oligomers thereof, their preparation and use for surface treatment

High-viscosity aqueous emulsions of functional alkoxysilanes, condensed oligomers thereof, organopolysiloxanes, their preparation and use for the surface treatment of inorganic materials High-viscosity aqueous oil-in-water emulsion which comprises from 50 to 90% by weight, based on the total weight of the emulsion, of functional alkoxysilanes and/or condensed oligomers thereof and/or organoalkoxysiloxanes, at least one emulsifier and water and has a pH of from 5 to 9 and a mean droplet size of the disperse phase of less than 5 &#x3bc;m, wherein the width of the droplet size distribution, expressed as the span (see formula (I)), is &#x3e;1.5, preferably from 3 to 8. The preparation of the emulsions having the desired droplet size distribution is carried out in apparatuses having at least one pressure stage at a pressure of from 2 to 15 MPa. The emulsion can be used for hydrophobicizing porous mineral building materials. 

High-viscosity aqueous emulsions of functional alkoxysilanes, condensed oligomers thereof, organopolysiloxanes, their preparation and use for surface treatment of inorganic materials

A process is provided for impregnating porous mineral substrates by a spray technique in which use is made of a gas-supported spraying assembly to apply liquid impregnating agent in a controlled manner to the substrate surface, the amount consumed being markedly less than the amount consumed in a conventional method of application by a flow-coating process.

Growing community of inventors

Wehr-Oeflingen, Germany

Bernd Bartkowiak