Abstract: An aqueous dispersion of polymer particles wherein the polymer comprises both (a) polar groups selected from amine, ureido and thioureido groups, and (b) poly (alkylene oxide) chains covalently bonded to the polymer, the polymer comprising at least 0.1% by weight of (a), at least 0.2% of (b) and from 0.4-9.0% of (a)+(b). Dispersions according to the invention are useful in latex paint compositions, and these compositions exhibit very good moisture resistance properties.

Abstract: This invention relates to aqueous dispersions of synthetic polymer particles, particularly those used as film-forming media in surface coating compositions.The problem of maintaining under moist conditions the adhesion to a substrate of a film formed from a surface coating composition having such an aqueous dispersion as a film former can be substantially overcome by using a dispersion wherein the film-forming polymer comprises (a) polar groups selected from amine, ureido and thioureido groups (b) a proportion of monomer units derived from acrylamide and methacrylamide, and (c) a proportion of poly(alkylene oxide). The proportions of these components present by weight of the film-forming polymer are at least 0.3% of (a), at least 0.3% of (b), at least 0.5% of (c) and from 1.4-9.0% of (a)+(b)+(c).These aqueous polymer dispersions may be used in interior or exterior surface coatings.