| abstract |
A polymeric emulsion comprising a (i) polymer, (ii) water, and (iii) a surfactant is useful for producing a water-resistant film. The polymer comprises about 25 to about 90 weight percent of a soft monomer whose homopolymer has a Tg of less than about -20 ·C, about 10 to about 75 weight percent of a hard monomer whose homopolymer has a Tg of greater than about 30 ·C, about 1 to about 5 weight percent of an olefinic carboxylic acid, and about 0.5 to about 5 weight percent of a cross-linking agent. Typically, the polymer comprises less than about 1 weight percent surfactant and has a Tg of about -50· to about 50 ·C and an average particle size of less than about 250 nm. The emulsion generally comprises at least about 40 weight percent solids and has a surface tension of at least about 45 dynes/cm. |