Aqs dispersions of monomer-free acrylate polymers - with addn of hydrocarbon solvent during or after polymn., giving water-resistant coatings

摘要

Odourless aq. dispersions of monomer-free (co)polymers of butyl acrylate, ethyl acrylate or methyl acrylate, or copolymers of (meth)acrylic acid or their esters, are obtd. by emulsion polymerisation in presence of emulsifiers and water-sol. redox systems at pH 2-6, and opt. organic peroxides; when the residual monomer content is constant at 0.2-1 wt. %, 0.1-3 wt. % w.r.t. monomer(s) of a specified perester or perketal is added. Not later than the end of the polymerisation, 1-10 wt. %, w.r.t. monomers), of a (cyclo)aliphatic and/or aromatic hydrocarbon, with b.pt. 50-350 degrees C., is added. Use of the dispersions as binders in pigmented coating compsns. for interior or exterior use is claimed. Films from the dispersions have improved water resistance.