| 摘要 |
PROBLEM TO BE SOLVED: To provide a new cement additive which enables enhancement of flowability of mortar or a concrete composition even when the amount of water used is reduced, and has a slump retention effect on concrete and is capable of inhibiting defective flowability of mortar or concrete immediately after mixing it at a low temperature from being caused, improving strength of such mortar or concrete and also reducing setting retardation of it. SOLUTION: This cement additive contains a copolymer which has, as its essential constituent monomer units, (a) a unit of a compound having an unsaturated bond(s); (b) a polyoxyalkylene alkenyl ether unit, and (c) a maleic-acid- based compound unit. |
