Patent ID: 7425596

Claim:
A method of dispersing aqueous suspensions of solids, the method comprising: blending block copolymers with an aqueous suspension of solids, the suspension of solids including hydraulic binders which include materials selected from the group consisting of cement, lime, gypsum, anhydrite and mixtures thereof, wherein the block copolymers are prepared by reacting a poly(alkylene oxide) compound of the general formula (I) in which R 1 =hydrogen, a C 1 —C 20 -alkyl radical, a cycloaliphatic C 5 —C 12 -cycloalkyl radical, an optionally substituted C 6 —C 14 -aryl radical; m=2 to 4; n=1 to 250; and Z is selected from the group of formulas III, IV, and V where Y═O or NR 2 R 2 =H,a C 1 —C 12 -alkyl radical, a C 6 —C 14 -aryl radical, or X=Cl or Br m′=1 to 4 n′=0 to 2, where R 3 =an optionally substituted C 6 —C 14 -arylene radical X=Cl or Br, in which R 4 is H, a C 1 —C 12 alkyl radical, a C 5 —C 8 -cycloalkyl radical, a C 6 —C 14 -aryl radical, optionally substituted by hydroxyl, carboxyl or sulfo groups, or and R 5 is C 1 —C 12 alkyl, C 6 —C 14 -aryl, or and R 1 , R 2 , m and n have the abovementioned meaning, with an ethylenically unsaturated monomer compound of the general formula (II) in a free radical, anionic or cationic polymerization in which R 6 and R 7 may be H, CH 3 , COOH or salts thereof, COOR 10 CONR 10 R 6 and R 9 together may be O—CO—O R 8 may be H, CH 3 or —CH 2 —COOR 10 R 9 may be COOR 10 , an optionally substituted C 6 —C 14 -aryl radical or OR 11 R 10 may be H, C 1 —C 12 -alkyl, C 1 —C 12 -hydroxyalkyl, R 11 may be acetyl, and R 1 , m and n have the abovementioned meaning.