| 摘要 |
PROBLEM TO BE SOLVED: To provide a cement dispersant by the use of which dispersion properties, dispersion retentivity and initial strength of concrete can highly be exhibited under a wide variety of concrete production conditions. SOLUTION: This cement dispersant contains a copolymer mixture I and another copolymer mixture II, wherein: the copolymer mixture I is obtained by copolymerizing a specific monomer A such as ethylenically unsaturated carboxylic acid derivative having a polyoxyalkylene group, and another specific monomer such as (meth)acrylic acid, and in the copolymerization, the A/B molar ratio is at least once changed in the process of this reaction; and the copolymer mixture II is obtained from such monomers A and B, similarly to the copolymer mixture I, however, has an average weight ratio of the monomer B to the total weight of the constituent monomers of the copolymers in the copolymer mixture II, different from that of the copolymer mixture I. |
