<p>A rheology modifier copolymer of formula (I) wherein A is a polyacidic vinyl monomer selected from maleic, fumaric, itaconic, citraconic and acid combinations thereof and anhydrides and salts thereof, B is an acrylic or methacrylic acid or salt thereof; C is a C1-C8 ester of (meth)acrylic acid; D is an associative monomer; and optionally E is a crosslinking monomer.</p>
