| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a cement additive a part of which is restrained from creeping in an intermediate layer of a layered compound such as cement and clay so that even a small amount of the cement additive exhibits satisfactory water-reducing performance and further excellent drying shrinkage reducing performance.SOLUTION: The cement additive contains a polyalkylene glycol compound which is obtained by bonding an organic residue, that exhibits adsorption capacity to at least one of metals, metal compounds and metal ions, to at least two terminals of a straight-chain or branched-chain polyalkylene glycol chain. The organic residue has: at least one functional group selected from the group consisting of a carbonyl group, a hydroxyl group, an amino group, a thiol group, a phosphate group, a phosphite group and a silane group; no vinyl monomer-derived carbon-carbon bond; and 700 or lower molecular weight.</p> |
