| 摘要 |
PROBLEM TO BE SOLVED: To provide a dispersant for cement, which can give to the cement compound high fluidity while restraining slump loss and high early strength at the same time and to provide the cement compound. SOLUTION: This dispersant is a water-soluble vinyl copolymer having 5,000-150,000 weight average molecular weight and 2-8 ratio of the weight average molecular weight/the number average molecular weight. The water-soluble vinyl copolymer is obtained by preparing an aqueous solution of a vinyl monomer group containing a specified urethane (meth)acrylate-based monomer and a specified (meth)acrylic acid-based monomer by≥75 mol% total amount of both monomers and 0.5/99.5 to 99.5/0.5 molar ratio of the former monomer/the latter monomer, adjusting the pH of the prepared aqueous solution to 3.0-7.0 and copolymerizing the vinyl monomer group radically in the aqueous solution. COPYRIGHT: (C)2004,JPO
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