WAESSRIGE POLYMERDISPERSION

摘要

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.