Elastomeric roof coatings with adhesion to weathered thermoplastic polyolefin (TPO) roofing membranes

The present invention provides elastomeric roof coatings made from emulsion copolymers having a glass transition temperature (Tg) of from -25°C to 20°C, a weight average molecular weight of from 50,000 to 150,000, a weight average particle size of from 100 to 500 nm, and copolymerized a monomer mixture of 20 wt.% or more, preferably 25 wt.% or more, of one or more hydrophobic monomer chosen from C 6 to C 24 alkyl (meth)acrylates and 0.2 to 5 wt.% of one or more ethylenically unsaturated acid functional monomer and containing aminosilanes which give excellent wet adhesion to weathered substrates, especially weathered thermoplastic polyolefin (TPO).