Redispersable cross-linkable dispersion powders

US6114423A · kind A · utility

Assignee

• Wacker Chemie AG · DE

Inventors

• Herbert Eck · Burghausen, DE
• Peter John · Burghausen, DE
• Hermann Lutz · Emmerting, DE

Key dates

• Filing date: Jan 20, 1998
• Grant date: Sep 5, 2000
• Expiry date: Jan 20, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P30/40
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A dispersion powder of water-insoluble copolymers of ethylenically unsaturated monomers and optionally, further additives, which are redispersible in water and obtained by: PA1 a) emulsion polymerizing, at a pH of 2 to 9, a comonomer mixture of at least one comonomer selected from vinyl esters of unbranched or branched alkylcarboxylic acids having 1 to 18 carbon atoms, methacrylic acid esters of unbranched or branched alcohols having 1 to 18 carbon atoms, acrylic acid esters of unbranched or branched alcohols having 1 to 18 carbon atoms, olefins, dienes, vinylaromatics and vinyl halides, and 0.05 to 15.0% by weight, based on the total weight of the comonomer mixture, of at least one silicon compound of the formula EQU CH.sub.2 .dbd.CH--(CH.sub.2).sub.m --SiR(OR').sub.2, PA1 where m=0-8 EQU CH.sub.2 .dbd.CR"--CO.sub.2 --(CH.sub.2).sub.n SiR(OR').sub.2 PA1 where n=1-6 ##STR1## b) spray drying aqueous dispersion, at a pH of 4 to 8 at a discharge temperature of 55 to 100.degree. C., before or after addition of any additives. The dispersion powders are useful as additives for hydraulic binders and binders in coating compositions and adhesives.