Water treatment polymers and methods of use thereof

Claim 1

Method of inhibiting the formation and deposition of calcium containing scale imparting compounds including calcium carbonate and calcium sulfate in an aqueous medium comprising adding to said aqueous medium from about 0.1-500 parts per million parts of said aqueous medium of (I) a water soluble polymer comprising repeat unit moieties (a) and (b) wherein said repeat unit (a) comprises the structure ##STR10## and wherein said repeat unit (b) comprises the structure ##STR11## wherein each R 1 is independently H or lower akyl (C 1 -C 3 ), R 2 is OH, or OM, M is a water soluble cation, R 3 is a hydroxy substituted alkylene radical having from about 1 to 6 carbon atoms, X is SO 3 , Z is H or a water soluble cation or cations, p is 1, the molar ratio x:y of said polymer being between about 10:1 to 1:5, wherein the number average molecular weight of said water soluble polymer is between about 1,500 to 500,000, and also adding to said aqueous medium from about 1-500 parts per million of (II) 2-phosphonobutane 1,2,4-tricarboxylic acid.