| abstract |
Provided is a cement dispersant which has excellent water-reducing ability, causes no setting retardation, and gives fresh concrete that has low consistency, is easy to knead, and has excellent applicability. The cement dispersant comprises a copolymer or a salt thereof, the copolymer being obtained by reacting the following ingredients (A) to (C): (A) an ester compound which is obtained by causing 0-10 mol of an alkylene oxide having 2-4 carbon atoms to add to 1 mol of one or more compounds represented by general formula (1) RO-(AO)n-H (1) (wherein R represents a C1-12 alkyl, A represents a C2-4 alkylene, and n is an integer of 0-7) and reacting the addition product with an a,ss-unsaturated carboxylic acid, wherein the proportion of the compounds represented by formula (1) wherein n is 3 or less is 5 mass% or less relative to the mass of all compounds represented by formula (1); (B) an a,ss-unsaturated carboxylic acid or a salt thereof; and (C) other copolymerizable monomer(s) used according to need. |