Patent ID: 9115493
Filing Date: 2015-08-25
Classification: C04B,C08F,C09D

Abstract:
1. An aqueous composition for coating roofing substrates comprising (i) one or more emulsion copolymer having a glass transition temperature (Tg) of from −45° C. to −10° C. having a weight average molecular weight of from 100,000 to 1,000,000 and a weight average particle size of from 80 to 500 nm, the emulsion copolymer comprising the copolymerization product of a monomer mixture of (a) from 65 weight percent to 94 weight percent of one or more C 4 to C 24 alkyl (meth)acrylates or a mixture of one or more C 8 to C 24 alkyl (meth)acrylates with butyl acrylate (BA), (b) from 8 to 34.65 weight percent of a hard vinyl monomer, (c) from 0.25 weight percent to 1.6 weight percent of itaconic acid (IA), and (d) 0.1 to 2.25 wt. % of one or more additional acid monomer chosen from a sulfur acid monomer and a combination of an ethylenically unsaturated carboxylic acid group containing monomer and a sulfur acid monomer, such that the total amount of sulfur acid monomer d) is from 0.03 to 0.8 weight percent and such that the total amount of monomers c) and d) is 2.5 weight percent or less, all monomer weight percents are based on the total solids in the monomer mixture; and (ii) one or more pigment, extender and/or filler in a total amount so that the composition has a pigment volume concentration (% PVC) of from 20 to 55, wherein the monomer mixture comprises 19.5 weight percent or less of any vinyl aromatic monomer; wherein, the monomer mixture comprises 11 weight percent or less of (meth)acrylonitrile; and, wherein, the monomer mixture comprises 20 weight percent or less of any hard vinyl monomer other than styrene or (meth)acrylonitrile, all monomer weight percents based on the total solids in the monomer mixture.