Aqueous compositions containing film forming polymer and sulfonic acid half ester salt, useful in coating mineral molded bodies, e.g. fibre-cement slabs, curbstones, stairs, plinths, form low water uptake coatings on such bodies

摘要

Surprisingly, compositions containing a film forming polymer form coatings of low water uptake when the compositions contains a salt of sulfuric acid half ester of an ethoxylated 10-20C alkanol as emulsifier. Aqueous compositions containing: (i) at least one polymer as film former, obtained from an ethylenically unsaturated monomer M, which is dispersed in the aqueous phase of the compositions and have a glass transition temperature Tg in the region of -25 to+80 deg C, and (ii) at least one anionic emulsifier selected from salts of formula (I): Alk = linear or branched saturated 10-18C alkyl; Et = 1,2-ethylene; n exceeds 20 to 40, and M<+> = monovalent cation or a cation equivalent, or mixtures of this salt optionally with various anionic emulsifiers are new. Independent claims are included for: (1) preparation of a coated mineral molded body with the composition deposited on at least one of its surfaces; (2) an aqueous mineral polymer dispersion obtainable by polymerization of an aqueous emulsion of at least one ethylenically unsaturated monomer M by radical emulsion polymerization in the presence of at least one radical polymerization initiator and at least two anionic emulsifying agents, comprising at least one salt of formula I and at least one salt of formula II below; (3) preparation of an aqueous polymer dispersion as in (2).