| abstract |
It is an object of the present invention to provide a cement admixture capable of exhibiting high cement dispersing ability at low addition levels, in particular capable of displaying excellent initial dispersing ability and dispersion retaining ability even in a high water reducing ratio range, and a cement composition in which this admixture is used. n A cement admixture comprising n two polymers, namely a polymer (A) and a polymer (B), as essential constituents in a ratio of polymer (A) to polymer (B) between 1 to 99/99 to 1% by mass, n wherein the polymer (A) is a polymer comprising, as essential constituent units, a constituent unit (I) derived from an unsaturated (poly)alkylene glycol ether monomer (a) and a constituent unit (II) derived from an unsaturated monocarboxylic acid monomer (b) and n wherein the constituent units (I) and (II) each accounts for not less than 1% by mass relative to all constituent units but the constituent unit (I) accounts for not more than 50 mole percent relative to all constituent units and, n wherein the polymer (B) is an oxyalkylene group- or polyoxyalkylene group- and carboxyl group-containing polymer. |